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RFID-radar newsletter
Newsletter No 36

19 December 2015

1. Using RFID to mark safe routes through landmines for vehicles - request from United Nations
2. Product range
3. Getting your own complete RFID/radar system

1. Using RFID to mark safe routes through landmines for vehicles - request from United Nations

The following is an extract from the 38 page RFP:

The United Nations (UNOPS) has issued a Request for proposal and plans to procure Radio Frequency Identification (RFID) equipment to demarcate roads and allow vehicles to automatically follow such markers.

The border between Sudan and South Sudan is estimated to be approximately 2200 km long and according to the UNISFA mandate, the UNISFA is to establish and patrol this border together with National Monitors from both Sudan and South Sudan. The border has never been physically marked or if marking had been done before, it would have been done during the colonial occupation of Sudan.

The UNMAS marking methods as prescribed in the International Mine Action Standards makes provision for a series of marking systems to be utilised when marking a cleared area prior to handing it over to the relevant authorities or the end user. These systems include the following:
a. Visual Reference Points
b. Visual constructed Bench Marks
c. Visual and sub-surface Starting Points
d. Visual and sub-surface Turning Points
e. Visual and subsurface Intermediate Points
f. Sub-surface marking by insertion of metal rods in ground to be located with a metal detector at all above mentioned Points
g. Accurate mapping of area

In addition, the above-mentioned points are linked on maps with the relevant distances and compass bearings between them. The coordinates of these points are also recorded either with handheld Global Positioning System (GPS) or for more accuracy, a Differential Global Positioning System (DGPS).

Over the years, marking systems within the Mine Action environment has been problematic and sustainability of marking has been subjected to the following factors:

A. Climatic conditions: Extreme weather conditions, such as high temperatures reduce the durability of visual markers. Painted pickets, rocks, barrier tape etc. are eroded by extreme temperatures, wind and rain and therefore lose the ability to be utilised as visual marker over a short period of time. Rain and floods also wash away marking over a period of time.

B. Theft: Theft is one of the biggest problems experienced with the marking of cleared or hazardous marking, especially in under-developed areas. Theft occurs when the marking materials have a monetary value, a use as a souvenir (for example mine warning signs) or as in many instances children use material from marking systems to be utilised in making toys. When hazardous areas are being fenced off with metal barbed wire, these wires are sought after for farmersí fences and safekeeping of cattle for example.

C. Bush Fires: In rural areas in the country, bush fires are seasonal occurrences. Prior to rainy seasons, local population such as cattle herders, farmers etc. will burn vast areas to ensure better grazing after the onset of the first rains. The fires are normally uncontrolled and burn and destroy any visual marking. Those type of marking that is not destroyed, are normally burnt to such a state that it is unrecognisable.

D. Intentional removal of marking: In areas where there are political differences, armed conflict or other unresolved land issues between the population, removal of any marking of hazardous or clearance marking can occur. Furthermore, is can also be removed by groups to deter opposition groups to enter an area and therefore create doubt in the opposition group as to the exact location of hazardous areas.

Until such time as there is well established routes or constructed roads, the identification of exact tracks or areas cleared by UNMAS will be problematic, especially after marking has deteriorated or been destroyed by mentioned factors including rain, theft etc.

Navigation by normal handheld GPS as well as DGPS by unqualified persons can be a tedious task and increases the risk of entering hazardous or dangerous areas. The use of DGPS is also very expensive, brought about by licencing fees, equipment and training. In addition, due to the periodic rotation of military personnel within the JBVMM Mission, local knowledge of the Area of Operations is also lost.

During research to find a sustainable and cost effective solution to the described marking problems, UNMAS concluded that utilisation of Radio Frequency Identification Service (RFID) will be the best way to the unique environment and challenges in demarcating the border and cleared areas within the border.

As RFID is an established and proven commercial technology, UNOPS (UNMAS/UNISFA) has the requirement to procure existing RFID technology and equipment that can be adapted in a cost effective way to be utilised in the UNMAS/UNISFA programme for the demarcation of the border area between Sudan and South Sudan. The successful company will provide the technology, equipment and the training for the implementation of the initial stage of the programme.

Phase 1:
The estimated length of the route for the phase I of this project is 100 km, which will be a combination of gravel roads, as well as extreme off road bush paths. The bidders will determine the quantity and the type of equipment necessary to cover the total length of the route. At the Phase 1, it is estimated that five (5) Radio Frequency Readers (scanners) will be sufficient to carry out the task. The scanners should easily locate these buried tags. Bidders should be able to guide the right location where tags are needed. The Reader will have a LED/LCD or a similar display screen, which will indicate to the driver/patrol that they are following the route accurately while in motion at the estimated speed of 40 km per hour
Phase 2
Planned to extend the coverage to 1000 km.

The above RFP was received from UNOPS by Trolley Scan on the 18th December 2015. We are one of the companies that were approached by the UNOPS about the concept.

Depending on the operating frequency and factors such as water content, RFID energy does penetrate the ground and allow buried transponders to be located with a reader.

One regular application of this approach is in locating the manholes for buried trunk fibreoptic cables. In these situations the cables and the access manholes are covered with soil after installation. The manhole covers are tagged with RFID transponders and in the event of maintenance being needed, the technician uses an RFID reader to locate the transponder and hence the manhole which can then be uncovered providing access.

Passive transponders would most probably be needed top be protected by suitable packaging and buried in the roadway. The lead vehicle in the convoy would have a reader system which would detect the transponder and provide identity and tracking information to the vehicle providing location information and guidance.

In a similar project Trolley Scan provide systems for unmanned trains that continuously read transponders along the track to control their speed and provide location information for command and control.

"This application could be one of the largest unconventional consumers of RFID todate."

Want more info. If you contact Mike Marsh at Trolley Scan we can provide you with a copy of the RFP from UNOPS.
The closing date is in a couple of weeks.

2. Product range
Trolley Scan are a manufacturer of UHF RFID systems.

Trolley Scan manufacture fixed readers, portable readers and RFID-radar systems (Real Time Locating systems that give accurate position information) as well as a variety of transponders for different applications. Transponders come in the form of passive transponders with operating ranges up to 20 metres and battery assisted transponders with an operating range up to 40 metres. Trolley Scan also combine some of these components into packages for end users which are supplied with the appropriate software. Typical applications are asset management, notebook tracking, equipment barriers, store control, sheep and cattle tracking, event logging and sports timing systems.

3. Getting your own complete RFID/radar system
You can order RFID systems from Trolleyscan.com

Trolley Scan also provide a starter RFID-radar system.

RFID-radar is the next generation of RFID equipment combining identity with position information using the same low-cost transponders.

The systems comprise a reader, antennas and 20 transponders.

These systems are already in use in 20 countries.

To order see
Order form

RFID-radar newsletter
Newsletter No 35

18 October 2015

1. The rewards of using established component suppliers

1. The rewards of using established component suppliers
For those of you not aware about the features of RFID radar - it is an amazing RFID system that can give the identity and position of transponders in its field of view, with accuracies of millimeters at ranges up to 40 meters. To do this it does not use any classic radar type approach of pulsed systems, or features such as power measurement, but rather uses very low interference techniques that allow precise measurements while allowing many systems to operate in close proximity. This is achieved by a very special design, using special high quality parts and four digital signal processors running about 75000 lines of code.

The performance of the Radar is exceptional in that during its soak testing, we monitor thousands of readings and find very minor data scatter even at 40 meters.

As the designer and manufacturer of the systems, we have come to appreciate working with mature component suppliers that can keep on making the special parts we use over the ten year period we have been making the system. Although manufacturers might bring new versions of products to market, as a system manufacturer it is essential that we are also able to get the older versions that have already been qualified for use in our systems.

The RFIDradar uses some very special parts that have specially been designed and manufactured for us. We hold stocks of these parts but when it comes to re-ordering, some of the manufacturers have to do a special manufacturing run for our parts as they are not off the shelf parts. This in some cases needs a 90 day turn around between the order and delivery as the parts are carefully tuned to deliver the required performance. This is where one appreciates dealing with companies that have been in business for decades and have the skills and resources to make special parts for customers.

Like our suppliers, we deliver stand alone systems that will work with past, current and future generations of computers and software, providing reliable measuring data for computer systems. We support our clients from 52 countries with support covering our earliest generations of equipment to our current. Any client can contact us with a problem and we will be able to get their system to full operation.

Although our design has been stable for many years, the recent banning of transport by air of equipment containing lithium batteries caused a redesign of the battery powered transponders to allow the batteries to be removed before shipment. This allowed us to also improve the performance of the transponders. The systems will work equally well with the older and the newer transponders but should get slightly more range with the newer generation.

RFID-radar newsletter
Newsletter No 34

22 June 2015

1. Interesting projects using RFID - RFID controls unmanned heavy vehicles

1. Interesting projects using RFID - RFID controls unmanned heavy vehicles
RFID is a sensing system that can be used with computer systems to provide some very useful systems.

For the past ten years, Trolley Scan have been providing adapted readers with special software, that allow unmanned trucks to move heavy loads very safely.

RFID can allow heavy vehicles to sense their current position when moving along a roadway and by knowing the distance between transponders and the time they are read, the speed can also be determined. This can be an independant system that does not need external signals such as GPS, and will also work when moving inside buildings.

Transponders are attached along the track and a reader on the vehicle detects the identity of each transponder as it passes over them. The computer system inside the vehicle has a table of the correct order the transponders will be passed and can detect immediately there is any component failure. The reader software has been specially created to provide status information to the computer controller so that any failure can immediately be detected.

The system uses passive transponders so that there is no maintenance involved in keeping the RFID system operational.

About 20 of these systems are in operation and the project has been running for the past ten years.

RFID-radar newsletter
Newsletter No 33

12 August 2014

1. Development of new range of transponders for radar
2. Using RFID-radar to steer robots

1. Development of new range of transponders for radar
In our earlier newsletter we reported that the freighting world had changed dramatically for shipping electronic goods as of the 1st April 2014. From that time on it has become extremely difficult to airfreight any electronic item that contained any form of battery. Any battery that used lithium was marked for special attention and was regarded as a hazardous cargo, and was not allowed in some countries to be shipped on an aircraft that carried passengers. We had two systems caught in transit by these new regulations, namely one being moved by a global courier and the other by a freight forwarder. Instead of taking a few days to do the shipment as in the past, it took nearly 30 days each for those two shipments to be delivered. The freight forwarder had his shipment rejected on three occasions by the airlines despite the goods having all the required hazardous cargo certificates. Eventually he shipped via a third country to bypass one of the bottlenecks. All this was over 18 very small watch batteries that were in the battery assisted transponders. These are long life batteries and are built inside the transponder in manufacture to power up the devices for five years. It seems that lithium is a particular problem for the airlines as their existing fire extinguishers have trouble dealing with a lithium fire. With the goods being classified as hazardous cargo the shipping cost are much higher than normal.

Trolley Scan have redesigned the battery assisted transponders in their product range to allow access to the batteries from outside the transponder. In the past the battery was inserted in the middle of the structure during manufacture, and was then encased in plastic and rubber to make a waterproof device. In the new design, a battery holder has been included in the case design so that the battery can be inserted and removed.

We now build the devices to order, soak test the devices, and then remove all the batteries prior to shipment. The client buys the same batteries from their local supplier and fits the batteries when the system arrives.

This is not an ideal solution as the waterproofing of the transponder has been compromised but it does allow the equipment to be delivered.

2. Using RFID-radar to steer robots
The RFID-radar has the ability to measure the angles of arrival of signals reaching the reader from a number of transponders virtually simultaneously. The range measurement to the transponders is speed limited and usually our clients are wanting to travel at a higher speed than the range features allow.

The clients want to make robot systems that can operate over large warehouses freely.

By placing many transponders around the area in which the robot will be operating, the robot is able to read the angles from many transponders at any instant, and from the angles of arrival solve its current position.

The reader does not do any of the solving of the position, but reports all the angles to a host computer on the robot which then does the position solution.

To build this system you need computer skills as you are processing complex geometric situations and there will also be an element of fuzzy logic to deal with obstructed radio paths and possible some multipath.

RFID-radar newsletter
Newsletter No 32

28 April 2014

1. Major changes to world trade in the past month
2. Energy conversion

1. Major changes to world trade in the past month
This weekend we have two radar systems in transit to overseas clients both with complicated shipping arrangements. Whereas we have shipped in the past about 500 such systems using couriers, the 1st April saw the introduction of new rules and measures that make the shipping of some goods nearly impossible. Even a major courier company like FEDEX said they could not transport the systems with the new rules.

Inside most watches, calculators, computer motherboards and virtually any device that can remember a date setting, lies a small coin cell battery that keeps the date chip running. These cell batteries usually contain lithium in small amounts to give a battery that has very low leakage and usually a five year operating life. It is these batteries that are the target of new regulations from the 1st April which make their transport by air or sea extremely difficult.

Since 2013, IATA (the airline association) has introduced new regulations that declared any form of lithium battery as a dangerous cargo. Prior to the 1st April, the small coin cells mentioned above were excluded in certain circumstances, but from the 1st April this exemption falls away and any item that includes one of these batteries is now classified as dangerous cargo and subject to new transport regulations. In most cases this involves special packaging, a limit on the number of batteries in the package, special labelling of the cargo and an accompanying lithium battery certificate even if the battery is encased inside an electronic system.

In the USA situation, for local transport, import or export, this cargo may not be transported on any passenger aircraft and can only be moved by "cargo only" aircraft.

There are further regulations concerning the lithium batteries, requiring them only to be made in approved UN certified factories.

In our radar system we provide transponders that have a 40 metre range and which contain one of these small batteries. The batteries are installed in manufacture and are deep inside the packaging of the transponder before the transponder is finally encased in a rubber sleeve. They are electrically disconnected during transport and are not accessible from outside the transponder.

The new transport rules are going to mean that we change the design of the transponder to either:-

  • 1) use a different chemistry rechargeable battery and supply a recharge circuit for users to recharge the encased battery. The leakage for rechargeable batteries is much higher than lithium batteries and typically a rechargeable battery will run flat in a storage situation in 3 months compared to the five years of a lithium battery.
  • 2) use an externally accessible battery holder so that the user can locally buy lithium batteries and install them themselves when they receive the equipment. We can then fly the equipment with no batteries included. This solution is further complicated in that the positioning of the battery in the transponder is critical in order to preserve the RF performance and its waterproof nature.
  • 2. Energy conversion
    A really impressive technology is developing at present relating to the useful conversions of solar energy.

    Solar panels are becoming quite cheap and have a long operating life (20 years if well made). However they are difficult to interface to harness the available power. A typical panel might have an open circuit voltage of 22 volts, a short circuit current of 3 amps and have an optimum power transfer point elsewhere say at 15 volts. In addition a cloud passing across the direct sun path might cause the output power to drop to just 10% of the energy compared to the energy without the cloud. All this means that one is getting continually fluctuating energy from the panels and it is very difficult to design for a steady load- especially something using a motor.

    In the past one might have stored the energy in some form of battery, but this gives very little of the potential energy available from the solar panel to a useful load. Batteries are expensive, difficult to charge and discharge quickly, have small capacities and a limited life.

    The ideal situation is to immediately convert the solar energy to mains electricity that is compatible with the supplied mains and to use the energy in the normal AC load of the building, reducing the amount of energy drawn from the municipal supply.

    You cannot use any inverter to convert the DC voltage from the solar panel to AC mains compatible energy. It has to be generated in exact phase and frequency with the incoming mains otherwise it is going to be vaporised.

    The type of inverter needed is called a Grid-Tie inverter.

    It is wired directly onto the mains supply and the solar panel provides the energy. The inverter continually monitors the solar panel and as soon as there is sufficient energy it starts to monitor the AC mains supply determining the frequency and the phase angles.

    It starts its inverter at the same frequency as the incoming mains supply but at a low output voltage and gets the two voltages in exact phase with each other. It then increases the output voltage to start supplying in phase electricity and using up the available solar power.

    On the solar input side it adjusts the load voltage to get maximum power transfer from the solar panel by monitoring the DC voltage and current to operate at the Maximum Power transfer point. It continually adjusts these values so that it can handle variations in the available solar power such as might happen with a cloud passing through the direct sun path.

    The inverter has another feature called islanding, which shuts down the entire process in the event of an incoming mains failure.

    Grid-Tie inverters have been around for a long time for major solar and wind turbine installations. They have however been quite expensive (US$1500 for a 15KVA system)

    The new development is in the form of micro grid-tie inverters which allow simple systems of 300 watts or 500 watts to be implemented in modular form. These are not wired into the main switch board of the establishment, but plug into a normal AC outlet in a room. They are also cascadable allowing many 300 watt or 500 watt units to work in parallel so that larger loads can be addressed. They also cost only about US$100 each.

    We have three of these systems running at present which generate about 40% of the electricity used during daytime. We have power meters on the incoming mains power supplied from the municipality and on the power supplied from the solar panels and continuously monitor the effectiveness of the system. When clouds pass over the setup one instantly observes the change in output from the solar network and the increase from the municipal network to keep the building load running optimally.

    Electricity meters that monitor the incoming supply from the municipality supply are becoming electronic based rather than the historic magnetic type. The electronic meters cannot determine the direction of the current flow and so it is important that one does not generate more electricity from the solar network than the building is using as any oversupply will flow back into the municipal network and generate a charge on the meter despite no electricity being used. Hence during times of full sun one can reduce the municipal consumption down to nearly zero using the grid tie inverters, but in cloudy conditions or when night falls, the building needs to run on municipal supply.

    At current electricity rates, we expect payback within 5 years without any form of solar subsidy.

    RFID-radar newsletter
    Newsletter No 31

    13 November 2013
    1. CellID - a new form of global tracking

    1. Cellid a new form of global tracking

    If you wanted to track a motor vehicle for example, over a large distance, there have been some recent developments in equipment that allow this to be done very cheaply. This new technology uses the cell phone network to identify the location and to transfer the message from the unit back to the requester.

    Previously one would use a GPS receiver to determine the position of the vehicle, and then some form of communications system to sent the answer to the requester. The negatives of the GPS solution are the cost, that two systems are needed (namely measuring the position and communicating the result), that the GPS antenna need to be in line of sight of the GPS satellites overhead, and that it does not work in the presence of high rise buildings or when inside a building.

    The CellId systems operate where ever a cell phone signal is present, in the open or inside a building. The antennas can be inside the device which does not need to be in line of site, but can for example be built into the bodywork of the vehicle.

    The CellId device is a spin off of cellphone technology. It can be packaged in a unit as small as 3cms x 3 cms by 1 cm, of which most of the volume is the battery system. It holds a SIM card which connects it to the cellphone network to read the location and to provide communications. The device is activated by sending an SMS from the requester to which it replies with the current position. Other versions include a vibration sensor which can initiate an SMS whenever the device is moved.

    Each cellphone tower, when communicating with a cellphone device, communicates the country code, the service provider code, the local area code and the cellid of the tower.

    The format looks like mcc=655,mnc=001,lac=150,cellid=15262.

    This represents the position of the tower which is communicating with the cellid device and typically is about 500 to 2000 metres from the cellid device.

    Various websites convert the above data back to a lat lon position of the tower and plot it on a map.

    A weakness of the system is that the database of the cell towers is not freely available in many countries and the individual service providers are not compelled to provide the information to the public. This has resulted in various volunteer organisations creating a public database by their volunteer members finding towers, extracting the cellid data from the communications with their cellphone, and submitting the description and location to the database for others to use.

    Trolley Scan DO NOT make the cellid devices, but we have been using them and testing them for the past few months. They are hugely useful for locating vehicles out on delivery or the like, where the exact position is not important but one wants to know approximately where on the delivery route the vehicle is currently.

    They are very cheap to operate and are very cheap to buy, and do not need a third party service provider to realise the service. They also can be used to locate stolen vehicles, being built into the bodywork and only activated in the event of a theft.

    RFID-radar newsletter
    Newsletter No 30

    6 June 2013

    1. Tracking nuclear storage containers
    2. Server attack - hitting the beehive

    1. Tracking nuclear storage containers
    Many countries store their spent nuclear fuel from their nuclear power stations in metal and concrete drums which are then buried underground.

    Trolley Scan were sent a few months ago a request by a nuclear plant operator to propose equipment for a system to track these containers using RFID. The tracking relates to empty containers before filling, filled containers on site and filled containers that are being transported to the storage area. The RFID transponders need to survive the burial process for many decades to provide positive identification of each container if they are excavated.

    The intention is to attach special transponders to the outside of the metal drums, and in the case of concrete drums to embed transponders in the concrete case.

    There are two interesting challenges to this proposal, namely the design of transponders to be buried in concrete, and protecting the transponders from the effects of close nuclear radiation.

    A properly designed antenna for an RF device resonates at its operating frequency giving effective magnification of the RF performance, in the same way that a tuning fork resonates at its design frequency to sound waves at its resonant frequency.

    When radio waves travel through dense materials, they no longer travel at the speed of light but travel slower which is a function of the relative dielectric constant of the material through which the wave is passing. This means that an antenna system that works in air will not work effectively when the antennas are encased in concrete and a new design is needed.

    Trolley Scan have experience in designing for concrete, having done a design to tag the large concrete road crash barriers used in road construction on motorways. The purpose was to provide positive identity for each concrete block and be able to read that identity while passing at speed for inventory purposes. A new antenna system was developed for the transponders which are encased in the concrete during casting and allow good reading ranges.

    Semiconductors have a problem operating in a zone of high radiation. Back in the 1960/70s before the age of microprocessors, digital systems were made primarily from a technology called TTL. This technology implemented gates, latches, counters and shift registers and from these modules computer systems were built. There were three ranges of the technology, namely commercial which could handle 0 to 70 degC, military which could handle -40 to 125 degC, and radiation hardened to be used in space applications where they might be bombarded by radiation. The problem with the radiation seems to be that it alters memory states of the modules and hence the values being stored.

    Whether this would be a problem with certain RFID systems is uncertain as there are limited facilities that can test the devices due to the radiation requirements. However there are certain RFID design issues that should minimise the impact of the radiation, such as having hard coded data in the RFID device rather than memory structures.

    Testing in-situ will have to be done before final answers can be given.

    2. Server attacks - hitting the beehive
    This section relates to some observations that would be of interest to readers who operate internet servers and please skip if not of interest.

    In our past newsletter we described how we had discovered a continual low level of security probing of our site on an organised basis from a very large number of slave computers worldwide. We identified 3000 of these machines and blocked them, and then the fun really started. We started a webpage and published lists of the attack sites and the number of attacks from each site, which really annoyed some people who organise the probes.

    Having had about 1100 attacks per day when we started the tempo was upped to 11000 per day three weeks later. It then dropped off back to 1000 per day and on the 7th April we had an instantaneous 40 fold increase to 40000 attacks for just one day. The bullet proof properties of our site withstood the onslaught. We then received emails saying that our site had been taken over, a fact we knew was false as we could inspect all activity in the log files. For the past two weeks the attack tempo has dropped to less than 500 per day, very few of which even make it past the first level of filtering.

    We now weekly publish details of the attackers and graph the attack tempo at


    Many site owners globally have requested copies of our statistics and the identities that we have resolved.

    We are now in the process of constructing a huge WHOIS database that allows us to reverse lookup from where the attacks are coming. This is showing up patterns of links between certain ISPs. We have about 250000 data points at present and look for situations where there seems to be a high level of coordination, especially in time and message content.

    For those interested in this subject, you want to research the story behind "dellpc.com".

    In short Dell Security division noted that a site had been registered called "dellpc.com". They approached the regulators in the USA claiming this name was close to their company identity and applied to have it transferred to their name. The registrant was not clearly identified except by a yahoo email address and did not oppose the transfer legally. When Dell started operating the domain, they found it receiving large emails that contained confidential corporate information from many important companies. It seems that this was a control node that had been designated in specially created viruses that had been inserted into the target companies computer systems, gathered data over a long period and sent the packed information to the control node.

    Dell went further and found the same registrant email address had been used on a number of similar sites which are also likely to be control nodes. The email address was unmanned and so it was not possible to find out who was the registrant. However they managed to find out that it was a specific lecturer in China as he gave the same email address when pressed for a current email address when registering for a conference. They now have published his biography together with photos of the person creating this network.

    We currently are trying to find the patterns from our data that might lead to the identities of control nodes.

    We have written some very clever programs for processing the large number of datapoints very quickly looking for patterns. From this experience, one can foresee a large demand for people with Mathematical degrees for developing search programs and finding patterns in data.

    Want more info such as a list of attacking servers?

    RFID-radar newsletter
    Newsletter No 29

    27 March 2013

    1. Different operation frequencies allocated to RFID
    2. Server attack

    1. Different operation frequencies allocated to RFID
    The most important criteria to select in choosing an RFID system is its operating frequency. The choice of frequency determines the performance that can be expected from the system.

    The world is divided into three regions for frequency plans which are then accepted or modified by the individual countries in the region. The regions are - Europe & Africa, North & South America, and Asia(excl Russia) with Australia.

    The regions draw up the masterplans for the management of the radio spectrum and these are then adapted and accepted by the individual countries in those regions. This means that for major issues there are blocks of frequencies allocated in the different regions, such as for example cell phones. Minor applications, such as RFID, are fitted in by the individual countries between the big blocks and as a result there are nearly 177 different plans for RFID globally.

    Because different frequencies will give different performance, there are five groups of frequencies allocated for RFID by the individual countries. These are typically

    1. 125kHz
    2. 13.56Mhz
    3. approx 900MHz
    4. approx 2.45GHz
    5. approx 5.8Ghz

    There are two modes of sending energy through space, namely magnetic and electric fields. Magnetic systems use coils to couple the energy into space and these coils can be quite small, but operating range is short. Electric field use antenna systems that are usually operating wavelength related - for example half wave dipole.

    The wavelength is the speed of light divided by operating frequency. The wavelength at 100MHz is 3 meters, 900Mhz is 33cms, 2.45Ghz is 12cms, and 5.8Ghz is 5cms.

    The electric field antenna collects energy passing and its collecting area is proportional to the wavelength squared. So a 900 Mhz system with a 16cm antenna size collects 7 times the energy that a 2.45GHz system can collect or 33 times the amount of energy a 5.8GHz system will collect. This reduction in energy collection with frequency means that a 900 Mhz is almost the ideal RFID frequency for passive systems having consideration for antenna size and operating range. Lower frequencies would give more performance but would have much larger antenna systems.

    For passive systems (that is where the transponder extracts its operating power from the energising field), typical ranges for the different operating frequencies are - 125KHz (2 centimetres), 13.56Mhz (1 metre), 900MHz (10 metres), 2.45GHz(1.2 metres) and 5.8Ghz (25 centimetres).

    The 125Khz and 13.56MHz systems are magnetic coupled which allow them to operate in situations where electric field systems cannot operate, such as underwater, inside the bodies of humans and animals, and even inside blocks of metal. The 125khz transponder can be made very small, the most common being a coil 1 millimetre in diameter and 11 millimetres long.

    In 1990 when the staff of Trolley Scan were involved in the development of a transponder that could be used for the labelling of items in a supermarket trolley, 900MHz as a frequency was only available in a few parts of the globe with many countries preferring that development happened at 2.45GHz, a frequency that was already allocated to microwave ovens which had very poor frequency stability.

    After Supertag(tm) was developed and demonstrated in South Africa(1994), the interest globally in RFID took off and countries slowly realised that they needed to allocate a frequency for RFID in the 900MHz region in order for their countries to stay competitive. By 2013 virtually every country in the world has finally allocated part of the spectrum at 900Mhz for RFID.

    Trolley Scan have a technical paper explaining these choices which can be requested Interested? - Use this link to be sent the white paper.

    2. Server attacks
    This section relates to some observations that would be of interest to readers who operate internet servers and please skip if not of interest.

    For the past 16 years Trolley Scan have been serving information from a stand alone webserver running a linux operating system. The server supplies about 2.5 million documents per annum in the form of HTML, PDF and JPG files. In the whole 16 years, on only about five occasions has it stopped and needed a reboot. Two of these stoppages have happened in the past three months and as a result we have been investigating the cause. Usually nobody looks at logfiles as everything is running smoothly until there is a problem.

    Particularly with what has recently happened with attacks in South Korea in the past weeks, internet security is becoming an issue.

    We found that the reason the machine had stopped was due to simultaneous attacks from about 300 machines distributed all over the globe on our server at virtually the same instant. This overloaded a stack causing the machine to stop. What was interesting about the attack was the distribution of the attacking servers and their time coordination. We have since limited the number of child processes that can be started at any time and made the machine bullet proof.

    On further analysis of the historical logfiles, we found that our machine was being probed by very many servers continuously. This takes the form of sending the server an email to a fictitious user on our server to see if our machine would acknowledge that the user is UNKNOWN. Once again the probing is coming from no single source but is routed through 3000 different slave servers around the world, but particularly from Russia, Belarus, Kazakistan and Vietnam. We have recorded about 80 000 of these attempts over the past 4 weeks.

    Because we have the logfiles and are experts at data processing and analysis, we find so far that about 3000 slave servers are being used to do this probing. They are connected as all the probing messages are the same with just part of the destination address changing. What is interesting is the use of individual slave servers is kept to once or so per week so that unless you have a long data set you will not notice the pattern. One can find the more important machines in the probing as they often use multiple IP addresses from the same server or group of servers.

    We then started blocking the probing from the more noticeable servers by listing them in the access.db file. This sent them an ACCESS DENIED message and they immediately knew that we knew who they were. This brought upon us a major storm, like hitting a bee hive. Whereas when we started this we were getting 1000 probes a day, we are now getting 9000 a day but have identified and blocked 90% of all probes. However new slave servers are being added all the time and whereas initially almost all the attacks were from Russia and Belarus, now many parts of the Western World are also involved in the attacks. These attacks are coordinated as at times all is very quiet and then the messages start coming fast and furious from all parts for an hour or so and then stop.

    In the past when we have had attacks, there were a few machines and you could see a coordination that might be with many people in a club all agreeing to do something at some time. We tracked these and blocked them and weathered the storm.

    This time we are convinced that the slave servers have been infected with a virus that allows some controlling body to coordinate and route targeted messages on their command and receive the feedback without the owners knowing. As the slave servers are only occasionally used for these messages, the existence of the virus is undetected.

    This whole exercise has become a James Bond like scenario. This server is really unimportant in the commercial sense as it has no commercial value and is just a repository for documents - i.e. it is not a bank server and it does not hold confidential information. It is only operating at 1% usage, it has a lot of spare resources,is a long way from being overloaded and is bulletproof after we closed the last loophole. Every time we get sent a probe, it is collected and added to a database that allows us to reverse understand the attacking structure and to see our impact on the probing.

    At present we are blocking 2984 servers that have been involved in multiple attacks on our server in the past four weeks, but we suspect this number might grow to 10000 when some of the servers that have only been used once are reused - unless someone discovers the virus in the client servers.

    We have published on our website a list of the top 200 (by frequency of attack) of the 2516 attack servers that have been active over the past month. We can also send a list on request of the attack servers.

    Want more info such as a list of attacking servers?

    RFID-radar newsletter
    Newsletter No 28

    4 February 2013

    1. Linking Android tablets to RFID readers

    1. Linking Android tablets to RFID readers
    Recently Trolley Scan were approached to deliver a solution by a refuse collection service which needed to monitor the exact location of their wheelie bins and provide information such as weight of refuse collected, exact location of the bin and time and date on an automated basis.

    The intention is to fit each of the wheelie bins (about 300 000) with a transponder in the lip of the bin, and have a reader on top of the compacting vehicle that would read the identity of the transponder as the contents of the bin were tipped into the compactor. A load cell would also be fitted on the lifting mechanism to measure the mass of the each bin as it is picked up and dropped off.

    Using a standard long range EcoTag RFID reader from Trolley Scan and standard EcoTag RFID transponders, the RFID part of the project is easy to implement.

    This is a data gathering application and an onboard computer is needed in each vehicle to determine the exact GPS position of the lift, the identity of the bin, the mass of the bin, the date and time and route number. All this information needs to be logged for future analysis and transferred to HQ either at the end of the route or via 3G during the route.

    The development of the Android based tablet has delivered some hardware that can drastically simplify the solution. The Android operating system connects modules inside tablets together. Typical modules that the operating system handles are GPS receivers, accelerometers, compass, WiFi, Bluetooth, 3G, USB ports, cameras, displays and keyboards. Due to mass production these devices have become very cheap costing between US$100 and US$200 for a 10 inch display.

    There is also a lot of recent development in programming languages for these devices allowing programs to be created that easily gather data from the sensors and save the information and generate reports.

    The negatives of using mass produced cheap tablets for a project that would have a long operating life are:

  • The production cycle of the tablets is short before new generations of equipment are released with newer operating systems which means problems with repair, spare parts and compatibility with software in future versions.
  • Currently the Android operating system is going through fast development with new versions being released frequently. The new versions do not seem to be compatible completely with the hardware of earlier versions. This means that often one will not be able to upgrade the operating system with existing hardware as developments happen.
  • The tablet itself is not necessarily rugged enough to cater with the operating environment inside a truck.
  • New modules for control by the Android operating system are being added all the time. At present the latest versions of Android can handle serial communications only via a specific RS232/USB adapter.
  • The advantages of using the cheap tablets are:

  • A complete package with an extensive range of sophisticated modules that are incorporated into the tablets, such as GPS sensors, WiFi, 3G.
  • It has a large display for man-machine interface.
  • It operates on low voltage using little power that makes it suitable for operating from the truck battery.
  • That programming languages have been developed for the android package to allow simple programming of the modules to easily extract the measurement data from the sensors.
  • Not all android tablets are the same as although they might have similar sensors, the physical packaging is often different - for example whether the antennas are internal to the tablet or an external antenna can be used.

    There seems to be a lot of potential for using cheap Android based tablets as data collection platforms in automated data collection projects where RFID systems are used. The version we have been using for development has an external GPS antenna which can be mounted on the roof of the compactor to accurately position the vehicle and the bin locations when being emptied.

    RFID-radar newsletter
    Newsletter No 27

    2 October 2012

    1. Getting a very low cost transponder
    2. Long term product stability

    1. Getting a very low cost transponder.
    If you listen to market researchers and potential large scale users, there is a large demand for very cheap RFID transponders. Low cost transponders are a requirement for success in some markets such as food retail if each item has to be labelled. How low is low cost - is not defined and it is partly the uncertainty that has stopped any large scale production happening. In this section we identify the technical issues in the manufacture of transponders.

    In the 1990s Trolley Scan was asked to take part in a survey to predict the component costs of transponders over the next five years. What was interesting from that survey based on the collective knowledge of companies producing low cost passive transponders, was that there were three major component costs for low cost transponders - namely

    1. the electronic chip
    2. the antenna which needs to interact with an electric field wave that is 30 centimetres in length
    3. assembly costs to mount the chip on the antenna structure and apply protective packaging for handling.

    The consensus at that time was that each of these components would make up a third of costs of making a transponder and this is most probably still true today.

    1) The electronic chip
    The electronic chip is made in a semiconductor foundry that has been optimised to make chips as small and cheaply as possible. It uses processes that are aimed at mass manufacturing where a minimum manufacturing volume is typically 100 000 at a time.

    The developments that happened that allowed a single chip to become the workhorse for RFID were those developments in chip technology that allowed the integration of UHF diodes, analogue circuitry and digital circuitry all on a single chip with a single manufacturing process . When the staff of Trolley Scan were involved in the development of the first passive transponders in 1990, we had a separate digital chip, an analogue chip, external high speed diodes and external capacitors in each transponder. At that time the digital and analogue chips had to be made in separate foundries as the chemicals and processes used in the one process poisoned the other process. Developments in the 1990s saw these technologies being merged and the UHF diodes able to operate efficiently at 1GHz being incorporated into the chip.

    An understanding of the developments in chip manufacture in silicon foundries explains why the technology called "printed electronics" as a solution to costs in RFID is not going to be viable. In the "printed electronics" process the aim is to print the transistor structures on cheaper substrates than silicon, and not need the high tolerance printing processes needed for semiconductor foundries. RFID at UHF frequencies currently pushes the boundaries in a silicon foundry and there is little chance that the huge technical gap between the "printed electronics" version and the conventional silicon substrate technology will close sufficiently for it to be a viable and cost effective replacement.

    2) Antenna structures.
    The antenna converts the energy travelling through the air into an electrical signal that can interact with the integrated chip on the transponder. The antenna is interacting with an electric field wave that is about 30 centimetres long and so the antenna is large physically compared to the very small integrated circuit. The antenna is so designed to resonate at its operating frequency, in the same way that a tuning fork resonates with an audio signal at its design frequency. The conversion of the electric field wave to electrical energy means that current is flowing in the legs of the antenna and this means that the antenna has to be made of a material with good conductivity.

    The simplest way to make a viable antenna is to use a copper clad substrate that is usually used for making printed circuit boards. However cheaper solutions are required. This has led to various initiatives to print the antenna with cheaper materials. A carbon paste is the cheapest form of conducting paste as carbon is so plentiful. However it is difficult to connect the electrical terminals of the integrated circuit to the carbon paste. Another problem is that if the antenna is flexed, hairline cracks appear in the dried paste which impede the current flow needed for the antenna to operate.

    Some solutions to this problem have been to electroplate copper onto the conducting paste to form a continuous surface that can bend without breaking the current flow, while another has been to use a silver based ink that is then heated and sintered. This last method is expensive and has also had issues with disposal at the end of life particularly in the EU as the antennas are then treated as hazardous waste needing special; disposal methods. As one can see, particularly due to its size and manufacturing methods, the antenna itself is a large part of the costs of a transponder.

    3)Transponder assembly
    Before high volume RFID transponder assembly needs arose, the smartcard technology had developed and assembly machines had been devised to assemble large volumes of credit card sized smartcards. It was possible to adapt these machines to make RFID transponders and this meant that production of millions of transponders was available almost from the outset. These machines attach the integrated circuit to the antenna foil, and then encapsulate the whole structure in its plastic packaging, as well as programming and testing the devices. However these assembly machines are complex and expensive.

    If RFID is going to be used in retail, then very high assembly volumes are needed. The limit on machine size seems to be a volume of 100 million transponders per annum per machine, which equates to about 7 transponders per second. This is about the limit on movement via motors as the inertia at higher speeds becomes so great that the motors have to become very large. So far it seems that only one of these machines has been built, but the current demand for transponders does not seem to be sufficient to keep it in operation. To meet the needs of RFID for retail, about 1 million of these machines would be needed.

    Price reduction with volume Generally the larger the production volume, the lower the costs as benefits from economy of scale are realised. However it does not mean that there are no costs. Because of the very high volumes that would be needed if retail items were to be tagged which would need very low cost transponders, there are only a few companies in the world that have the manufacturing equipment and skills to run a very large scale production operation. Before these companies would become involved, the price of the transponders needs to be high enough so that these companies could make a profit on the large investment they would need to make to build high volume assembly equipment.

    One has to question if any of the companies involved in RFID transponder manufacture are driven by the desire to deliver very cheap transponders. RFID is such a pervasive solution that its success is not dependent on satisfying the Fast Moving Goods market for retail tagging. There are many applications that can afford a higher value transponder that can allow the manufacturers to make some profit. As the higher value markets saturate in the future, and as more companies gain experience in very high volume delivery, then possibly the retail market can be addressed.

    2. Long term product stability
    RFID systems are the data capture component of many computer systems. Usage starts out as small test pilot studies and then more equipment is ordered in the form of readers and transponders as the application grows. For many users, the expectation is that the new transponders bought will be exactly compatible with the installed readers they are currently using so that the application can grow seamlessly.

    Clients of Trolley Scan in 52 countries are assured that our new generation transponders will be compatible with previous generations that have been supplied over the past fourteen years. Newer solutions are always in development, but parts and compatible components are available for all equipment provided over the past fourteen years.

    RFID-radar newsletter
    Newsletter No 26

    3 July 2012

    1 Radar measurements under computer monitoring.
    Radar measurements under computer monitoring.
    RFID-radar(tm) is an RFID system that can measure very accurately the distance from a transponder to the reader, with millimeter precision at distances up to 40 meters. Because of its long term stability using the wavelength of the operating frequency as its measuring reference - the system has the ability to detect long term slight movement in structures such as bridges, dam walls, mine roofes, and buildings.

    One of the uses is to detect movement and sound an alarm to provide early warning of a potential failure.

    The radar makes thousands of measurements which are passed onto the computer. The computer needs to analyse the readings continuously to check that movement has not occured that is outside acceptable limits. However the program needs to use a type of fuzzy logic so that it does not trigger when the radio waves between the transponder and the reader are disturbed such as when a bird flies through the zone.

    RFID-radar newsletter
    Newsletter No 25

    28 November 2011

    How good is the radar range measuring ability.

    Trolley Scan (Pty) Ltd makes a variety of UHF RFID readers, Radars and transponders. These systems are the sensor components of computer systems for a variety of applications. In this newsletter we describe some of the application trends for which our systems are being ordered.

    How good is the radar range measuring ability.
    The radar is a unique RFID based system that has the ability to measure accurately the radio path length the signal travels from the transponder to the reader. It has been designed not to use high interference techniques to make the measurement, such as might be used in military and airtraffic type situations - but rather low power, low interference techniques that causes virtually no interference, allowing many systems to operate in close proximity, and yet measuring accurately.

    To get accurate measurements, the radio path between the transponder and the reader should not be obstructed or else the radio path would have to travel an extra distance and this extended distance would be what is measured.

    Another factor to bear in mind is that the radio path is the vector sum of the direct path and all the reflected paths. The reflections come from any hard objects such as floors, walls cabinets etc. The reflected paths are likely to be different length to the direct path and hence can contaminate the direct path measurement. However energy in the reflected paths depends on the reflectivity of the reflector surface, and the extra distance the reflected signal has to travel, as energy in radio signals decreases by the inverse square of the distance.

    So the ideal situation for the best measurements would be that there is a strong unobstructed direct path, and that the reflected paths are much longer than the direct path meaning they are much weaker when they arrive at the reader.

    The radar exhibits millimeter sensitivity when operating in RELATIVE mode, able to resolve movements as small as 1 millimeter. Recent tests in a survey laboratory of a European University matching the system against other technologies used for precision measurement, has shown the basic accuracy of this method of measurement used in the RFID-radar, as well as what happens if the reflected paths are strong compared to the direct path.

    Because the RFID-radar measures the radio path length using physical parameters such as the operating frequency wavelength, precision is constant over the full range, from 40 meters to as close as a couple of meters.

    To find out details of the system see http://rfid-radar.com/

    RFID-radar newsletter
    Newsletter No 24

    31 May 2011

    1 Measurement of movement of structures
    2 Measurement of power lines

    Trolley Scan (Pty) Ltd makes a variety of UHF RFID readers, Radars and transponders. These systems are the sensor components of computer systems for a variety of applications.

    In this newsletter we describe some of the application trends for which our systems are being ordered.

    Measurement of movement of structures
    Trolley Scan also provide a unique system called an RFID-radar. This system measures the distance radio signals travel from the transponder to the reader and can give the 2D location simultaneously of a number of transponders up to distances of 40 meters. Despite using a similar narrow bandwidth as is used by our RFID readers, the system is able to monitor movements quickly with the precision of millimeters even for transponders as far as 40 meters away.

    The precision of the system, the ability to monitor up to 50 transponders simultaneously, the relative low cost, and the ability to move the reader from site to site to detect long term movement of structures, has meant that companies from a number of countries are using the system to detect movement in structures such as dam walls, bridges, buildings and tunnels. The system is suitable for permanent installation and continuous monitoring at a remote location in order to have an early detection of potential failures.

    Measurement of power lines
    Power lines carry the electricity from the power stations to the consumers. These structures are becoming more loaded as the demand for electricity increases, as the systems age and parallel lines suffer temporary failure, and as resistance from the public increases to allowing new lines to be built in their vicinity.

    The current flowing in the copper wires together with the resistance of the copper wire causes losses which cause local heating of the wires which causes expansion of the conductors and hence sagging of the lines. Additional current due to a failure of a parrallel route causes additional losses and hence more sagging. When too much sagging occurs there is potential for a dangerous situation to develops or a failure if they touch the ground.

    RFID-radar has the unique ability to remotely monitor the amount of sagging. Attaching a passive long range transponder permanently to the power conductors of the power line, allow the RFID-radar to measure the height of the transponders/conductors remotely to monitor the sagging. The advantage of RFID over other systems is that they transponder is electrically isolated from all the other conductors and can be measured using radio waves without influencing the integrity of the power lines.

    RFID-radar newsletter
    Newsletter No 23

    4 December 2009

    1) New SURVEY mode added to RFID-radar capabilities
    2) New RFID concept testing

    New SURVEY mode added to RFID-radar capabilities
    Readers of these newsletters will be aware that the RFID-radar equipment, designed and supplied by Trolley Scan (Pty) Ltd, can identify and measure the position of many tags in the reader zone simultaneously. It also has features that can continuously monitor the length of the radio path between these transponders and the reader, and that the system can detect changes in distance as small as 1 millimetre at distances up to 40 metres. This is useful for continually monitoring the movement of structures with wind and water loading, or movement of bridges with different traffic loading.

    Trolley Scan have now added a new SURVEY mode to the system to allow the accurate long term measurement of structures with millimetre precision. The new mode allows the reader equipment to be removed from the site for long periods and later repositioned to measure the movement of the structures in the intervening period. This allows movement of structures like retaining walls in landslide prone areas, swelling of dam walls with different water levels and time, movement of walls and roofs in tunnels, and similar applications.

    Transponders are attached to the structure being monitored and the reader setup at a distance so that it can measure the radio path length to all the transponders. These measurements are saved. The reader equipment is then moved to other sites or storage. When the movement is to be checked, the reader is repositioned, a new set of measurements to the individual transponders recorded, and movement calculated.

    The new SURVEY mode is a low cost application of measuring technology allowing potentially dangerous situations to be monitored without the need of highly skilled operators or expensive equipment such as laser range measuring equipment.

    A brochure on the new system can be downloaded at www.rfid-radar.com

    New RFID concept testing
    In our past newsletter we announced that Trolley Scan were in the process of developing a new concept in RFID that would complement our existing product range of RFID readers, RFID-radar systems and transponders.

    The new concept will provide solutions for many users who in the past were limited by what RFID could do for their problems.

    Since the last newsletter our prototype system has been involved in field trials with very encouraging results.

    Trolley Scan are currently developing the commercial version from the prototype designs.

    Watch this newsletter for further developments.

    RFID-radar newsletter
    Newsletter No 22

    26th May 2009

    Leap in the performance of UHF passive transponder technology

    In this newsletter we detail another major performance achievement for passive UHF RFID transponders.

    Another leap in the performance of UHF passive transponder technology
    The distance is 25.6 metres and the transponder is attached to a metal item!!.

    This is the functional distance from the reader, as measured with the RFID-radar, of the new generation passive UHF transponder developed by Trolley Scan. UHF transponders attached to metal items are another problem situation addressed by the Trolley Scan development.

    Passive transponders do not have their own onboard source of power but extract operating power from the energising field of the reader.

    Previously, the maximum range with passive transponders with Trolley Scan readers was 13 metres.

    The impressive performance comes from the combination of a new integrated circuit specially made for Trolley Scan and from Trolley Scan's spectacular RF antenna developments for transponders.

    The new transponder has been specifically designed to be used with tracking laptop computers and office equipment, but also finds use in tagging metal items.

    The actual operating range achieved with the new transponder is not important. Trolley Scan have for a long time supplied battery assisted transponders that had a 40 metre range, and this improvement just means lower costs, increasing operating life from a few months to 100 years, and providing simpler technology for medium range situations.

    What the development does signify is how passive types of transponders are moving into applications that in the past could only be satisfied with battery assisted and active type transponders. It also allows progress on the development of low power technology to be accurately measured.

    By way of an explanation for those technically interested.
    The staff at Trolley Scan were involved in the first developments of UHF transponders for retail applications, namely the development of Supertag in 1990 in Pretoria, South Africa.
    At that time we aimed to build a single chip transponder for use in tagging items in a grocery trolley. Then semiconductor technology was at such a stage of development that there were analogue type devices which could handle RF components, and a separate type of technology was in use for digital circuitry for data handling. Hence we ended up with two chips on each transponder. About ten years later single chip devices were practical that had both the RF and the digital circuitry on a single device and single chip transponders became available.

    The transponders get their power from the energising field and to visualise the power distribution back in 1990, we made a number of small dipoles with light emitting diodes. Attaching these to the wall of the office and aiming the energising antennas at the wall from about 3 metres away, together with a fair size RF power generator, we could get the LEDs to glow if they were in the main beam and hence see the power distribution. Those devices needed about 54 milliwatts of power in the collecting area and had an operating range of about three metres with the transmitters and antennas we then used. The two chip transponders needed similar power.

    Since January 2004, Trolley Scan have been supplying 200uW versions of transponders, that is a 250 times improvement on the originals. We now have a new transponder which is also passive, is attached to metal items, and uses just 40 microwatts (uW) of power, that is 1350 times less power than the originals.

    This dramatic improvement over time, has meant greatly increased range for operation. It also has led to reduced energising power being needed from the reader, which means smaller RF amplifiers and the ability to use lower gain antennas which can spread the power over a wider angle increasing the area of coverage. The lower power needs of the new transponders also means that portable readers which can operate on batteries for a reasonable time and yet give a 10 metre read range are practical.

    Trolley Scan make UHF RFID fixed readers. UHF portable readers, UHF RFID-radar systems and a range of transponders for different packaging requirements. The new transponder technology is compatible with all the reader products made by Trolley Scan and with all the earlier ranges of transponders.

    RFID-radar newsletter
    Newsletter No 21

    24 April 2009

    1) Development directions for RFID

    Development directions for RFID
    In 2010 we here in South Africa will be hosting one of the globe's largest media and sporting events, namely the 2010 FIFA Soccer World Cup. Technology is going to cause an interesting split in viewers of this event. Some will want high bandwidth communications so that they can watch it on a 5 centimetre cell phone screen, while others will want 42 inch screens with high definition satellite feeds. The people watching on the cellphones are never really going to know what is going on in the game, but they are going to feel good about their application of technology.

    In the same way, RFID is a technology that is suitable for some applications and not necessarily for others. RFID is a rapidly developing technology that is steadily finding its niche applications and it might be worthwhile to consider the directions of some of those developments.

    RFID is a data capture technology that allows the identity of items that are in close proximity to a reader to be communicated to a computer system for processing. It can read large numbers of identities in a zone, very quickly, accurately, and within radio distance of the reader. It can be made at very low cost which means that relatively inexpensive items can be cost effectively labelled. What makes it useful is when it is combined with the correct software application to manage these large amounts of data and generate simple, human compatible outputs.

    The ultimate application of RFID is in reading the contents of a supermarket trolley, an application that was first demonstrated in South Africa in 1994. Although technically RFID can meet this challenge, it is not a commercially viable application due to the high cost of the transponders.

    There are a number of new developments happening that are improving RFID.

    1)Lower power RF performance.
    As passive transponders operate on energy received in the form of radio power, and as this radio energy that is available degrades with distance, major developments are taking place to produce lower powered transponders. These developments focus both on the radio properties and the intrinsic operating powers of the transponders. The lower power developments mean that passive transponders are replacing the former active types of transponders due to their increased range and lower costs. The lower power devices also result in the viability of portable reader systems with good operating ranges and good battery life.

    2)Range information
    When transponder operating powers were high and ranges short, location of the transponders was not an issue as they were immediately in front of the reader. As ranges increased beyond 6 metres and approach up to 40 metres, it has become important to know the position of the transponder relative to the reader so that the item can be easily physically identified. These longer ranges mean that a single reader can now monitor an area that in the past had to be covered by many readers. This has resulted in Real Time Locating Systems (such as RFID-radar) moving into the RFID-reader market space.

    3)Manufacturing cost
    For many years there has been a wish to have very low cost transponders, especially by high volume users. Those who understand the issues realise that there is a floor to the pricing and very low cost parts are not going to be a reality. There are three major cost centres to making transponders, namely the chip, the antenna and the assembly/packaging. In a survey we were part of a few years ago, it became apparent from participants that roughly one third of the costs can be assigned to each of these centres.

    4)Smaller antenna size
    To transfer energy by radio means, antennas are used to convert electrical signals to radio waves and vice versa. The size of these antennas are dependant on the operating frequency of the systems. Breaking the relationship of size/frequency generally results in a drastic reduction in effectiveness. Users would like antenna systems that are as small as possible but still effective.

    5)RF interference
    As RFID systems become more popular it is going to be more likely that one RFID reader will interfere with another RFID reader close by as many users try to share the same allocated radio spectrum. Attention is going to have to be given to the interference profile of the different types of protocols. At present there are low interference tag-talks-first and high interference reader-talks-first protocols.

    6)Increasing dynamic range
    RFID readers are amazing pieces of technology, detecting very weak signals from transponders while in the presence of relatively strong energising signals. As the operating range of systems has been increasing, the readers have had to simultaneously detect transmissions from transponders that are very close to the reader and those that are very far. This has to be done without changing the amplification of the readers so as not to miss any transmission.

    7)New protocols
    Presently the simple protocols in use require each transponders to have a unique identity to be identified correctly. There are available more advanced RFID protocols that allow many transponders with the same identity number to be accurately identified and counted, protocols where the uniqueness of the data is not used for identity. In future systems where only product numbers are needed, these advanced protocols will be needed.

    RFID-radar newsletter
    Newsletter No 20

    24 February 2009

    1) New developments in passive transponder technology

    New developments in passive transponder technology
    One of the key parameters to measure the technological progress of RFID, is to monitor the amount of RF energy needed to operate a passive transponder. The transponder collects its energy from the energising field of the reader, and when the amount collected reaches the operating requirement, the transponder is powered-up and can function properly.

    The energy density from the reader decreases as the inverse square of the distance - that is every doubling of distance requires four times as much power, or a tag 10 meters from a reader only receives 1% of the power density of a tag 1 meter away. Hence by reducing the amount of energy needed to operate a transponder, operating ranges can be increased, operating power of readers can be reduced and portable equipment operating on battery power becomes more viable.

    In its simplest form, a transponder comprising a dipole antenna with a five volt logic circuit would need 54 milliwatts of power. For the past six years Trolley Scan have been providing passive transponders that could operate on just 200 microwatts of power - that is 260 times more efficient than a simple transponder and that could be read by a Trolley Scan reader at distances as far as 13 meters.

    Trolley Scan have in the past few weeks been developing a new design, one that operates on just 112 microwatts of power. This is nearly 500 times more efficient than a standard transponder and will give an operating range for a simple passive transponder of about 18 meters, while still being as small as a credit card.

    Passive transponders are dramatically cheaper and more green than their active transponder counterparts. There was a time when passive transponders had operating ranges of only 1 meter if you were lucky - and otherwise you had to use active transponders which contain onboard batteries. As the operating sensitivity of the passive transponders reduce so passive technology is replacing active transponder technology - reducing costs and increasing transponder operating life.

    The new transponders will be part of the standard RFID portfolio available from Trolley Scan within the next few months.

    RFID-radar newsletter
    Newsletter No 19

    9th September 2008

    1) Future advancements in RFID applications
    2) A portfolio of RFID technologies

    Future advancements in RFID applications
    RFID hardware systems form part of information gathering technology. The systems will capture the identities of items to which transponders are attached. - some at distances up to 10 metres, with up to 800 tags in a zone at a time and at read rates up to 70 per second. Data from the reader, which is arriving much faster than can be processed by the human mind, is usually interpreted by a computer attached to the reader.

    Large improvements in productivity are going to be realised when databases that are resident in computer systems are linked to the received RFID data and interpreted correctly. An example of linking databases to RFID would be in the tracking by tour operators of their clients' luggage on a bus trip - where the guide would want to be able to check that all the luggage is present and ready for loading when the bus departs from the hotel, and knowing what luggage should be delivered to which hotel room in the evening at the next stop.

    RFID applications usually require a simple program running on a computer, a program that in the past could typically be written by a high-school student. Unfortunately the computer "program-creating" skills of the world seem no longer to be a skill that resides in every home, even although most homes have numerous computer systems.

    Basically most applications for RFID in small businesses are the same. Whether you are running an asset management system, a security system to control the removal of your assets from your premises, a program to track deliveries from your vehicles or an access control system - they have remarkable similarity in structure of the computer software. This is not a widely published fact as there is a strong industry writing middleware, bloatware, and "you_will_forever_be_poor-ware"!!

    Trolley Scan have been developing a suite of pseudo object orientated application software that integrate with their RFID hardware systems to provide the solutions to most common RFID applications. Basically most productivity applications involve interacting with the RFID hardware, interacting with a series of databases, fitting the information to a set of rules, and generating reports, alarms and notifications. These programs receive data from readers, look up and maintain databases, generate reports and alarms, and email warnings if needed.

    A portfolio of RFID technologies
    RFID is a new technology that is rapidly evolving as new developments are brought to the market. Range performance of passive transponders is increasing, reader energies are dropping, and more compact packaging of reader systems are being developed.

    Currently there are three separate lines of products for UHF readers from companies like Trolley Scan.

    a) Fixed readers which are often mains operated and can monitor transponders entering a zone up to 13 metres in front of the antennas with up to 800 transponders in a zone and travelling up to 300kph.

    b) Portable readers that are linked by Bluetooth type technologies to laptop computers forming a mobile data capture and processing system. Due to the low power abilities of Ecotag type transponders, battery operated reader equipment is viable and can read tags up to 8 metres range for long periods.

    c) RFID-radar systems which can measure the identity, and accurately the range and position of multiple transponders in a zone at a time. Despite these measurements being accurate, they use very little bandwidth allowing many RFID systems to operate in close proximity. Used in conjunction with battery operated transponders, useful ranges of up to 40 metres are achievable.

    In addition there are a variety of different forms of passive and active transponders packaged in different forms for different applications. These might be credit card sized, thin wire types, tags for notebook computers, or long range battery-assisted types where the plastic of the housing forms a focussing lens.

    RFID-radar newsletter
    Newsletter No 18

    1 September 2007

    1) Monitoring the integrity of bridges and large structures
    2) New uses where RFID technologies are being applied.

    Monitoring the integrity of bridges and large structures
    The tragic collapse of the motorway bridge over the Mississippi River at Minneapolis/St Paul highlights a need for continuous electronic monitoring of key structures.

    RFID-radar measures the radio path a signal travels from a transponder back to the reader. It is able to continuously monitor the distance from up to 50 transponders and the reader simultaneously. The RFID-radar has two modes of operation, the absolute mode which measures actual distances to an accuracy of 0.5 meters, and a RELATIVE mode which can detect movements about a reference in MILLIMETER precision.

    It is the RELATIVE mode with the millimeter precision which is particularly of relevance in this application.

    A reading station established forty meters to the side of the structure could continuously monitor the movement of a number of transponders that are stuck to the side of the bridge deck measuring the movement of all transponders relative to the reader 24 hours a day in all weather and traffic conditions.

    As the radar uses just 10kHz of RF bandwidth, a number of systems can be used at the same structure with no interference between systems. As the transponders are simple and cheap, the cost of the monitoring system would be relatively inexpensive.

    By monitoring the movement of the transponders in all weather and traffic patterns, a pattern could be established for normal safe operation, and warnings sent if the movements happen beyond the safety envelope.

    New uses where RFID technologies are being applied.
    RFID-radar represents the most advanced form of RFID available at present, giving both the identity and the location of multiple cheap transponders in its reader zone, while using only a small amount of radio spectrum.

    New clients are many Universities that have been setting up RFID research laboratories and have bought systems to allow their students and post graduates access to the next generation of RFID equipment. This includes the supercomputer research centre of one University who have bought their second Trolley Scan supplied system. Companies developing logistic systems for warehousing and vehicle location in loading yards, monitoring the exact location of people in an office or building for safety issues, and monitoring in 3D space the position of monitoring equipment to profile fields. Other applications where interest has been shown is in monitoring the movement patterns of bed clothes of patients in a hospital to determine when nursing intervention is needed.

    RFID-radar newsletter
    Newsletter No 17

    11 June 2007

    1) Major technical achievement - a small form tag with a long range
    2) The direction of development of RFID

    Major technical achievement - a small form tag with a long range
    Every once in a while a major technical achievement is realised and another milestone has now been reached.

    Trolley Scan announce the develpment of a slightly larger-than-credit-card sized tag that is compatible with both the RFID reader and the RFID-radar products, and which is 600 times more sensitive than the standard 200uW credit card sized tag that they supply. This additional sensitivity translates into increased operating range with a smaller sized tag.

    Trolley Scan have developed a 0,3uW Rf power transponder that is housed in a 90mm by 60 mm by 8mm block of polypropylene plastic and which is covered by a strong rubber covering. The tag is a backscatter transponder that will respond to signals over an 860Mhz to 960MHz bandwidth, giving an operating range of up to 40 meters when illuminated with a 2 watt energising signal.

    To achieve this performance was a significant technical challenge that took approximately six months. It is a complex device. When used with Trolley Scan RFID readers it will give its identity over the range from 1 cm to 40 meters, and with the RFID-radar it will give the identity and the exact position.

    Information for the technically orientated
    For radio systems the unit of dimension relating to performance is the length of a half wavelength of the radio frequency wave, which at UHF RFID frequencies is approximately 16cms.

    Antennas that have a dimension of half wavelength are efficient and RFID is about optimising efficiency. When you shorten antennas to less than half wavelength, the efficiecy drops off dramatically (for example halving the dimensions can lose 97% of the performance).

    A second factor is that the antennas are influenced electrically by items that are within the half wavelength zone of the transponder. These items influence the waves arriving at the antenna and usually degrade the performance of the transponder when it is attached to different items such as concrete blocks or metal items.

    When designers leave the half wave length dimensions, a property called the impedance of the antenna changes dramatically which influences the transfer of power between the chip and the antenna and hence the efficiency of the transponder system. In some cases these changes can be compensated for in a simple manner, and in other cases the fix is very complex.

    The challenge was to develop a transponder that would be very sensitive, would have a form factor similar to a credit card, and would not be strongly influenced by items to which the transponder was attached.

    The new transponder is about half the physical size of the already successful Claymore tag used with the RFID-radar, and yet gives nearly the same range performance

    The direction of development of RFID
    Readers of this and other newsletters relating to RFID will realise that RFID is a rapidly developing technology where concepts that were not possible yesterday are now possible. Today we announce a small form transponder with massive performance. A short while ago we announced the development of RFID-radar, where the same tag that in the past could only be used for identity, can now be used in real time locating systems for identity and position information.

    The Trolley Scan staff have been involved in the development of RFID since the first supermarket scanning system 17 years ago, have systems in operation in 49 countries, are in contact with 4500 companies monthly; and as a result have been asked for input on almost every concept of using RFID going on in the world today.

    In this time, many competitors have come and many have gone, misreading what the market wanted, what was commercially viable, and what changes technology would cause. The Press and Market Research companies have hyped the potential of RFID way beyond what could be delivered,not realising that market pull is not a solution alone to the problem of producing an item in large volume, that there have to be factories and there has to be an attractive market price.

    RFID is primarily a data input device into a computer system for a software application. When an item comes within range of a reader, the reader tells the computer system about the presence of the item.

    RFID systems compete with barcoding systems technology and handwritten/keyboard capture systems. The advantage RFID systems have over its competitors, is the range at which it can operate to retrieve data, the accuracy, and the speed of collecting data.

    If only one item is moving past a monitoring point an hour, then there is little benefit to using RFID over say a keyboard entered data. If a thousand items are passing, then RFID is essential for accuracy, speed and simplicity.

    There is also a lot of confusion about the role of RFID and the role of software in an application. Tracking is a function of software while RFID is a function of data capture. There is a recent press report about RFID tracking of a ship bringing goods from the Far East to Europe. Unless there is a large RFID tag on the side of the ship, this is actually a story about a software package that takes data from many sensors (for example the ship's location from its GPS receiver) and condenses the data into an understandable form.

    Recently a retailer in the USA said that RFID had reduced out of stock items on its shelf by 25%. Since the retailer knows what is entering its store via delivery notes, and what is sold via the checkouts, it is their poor use of the abilities of software that has kept them in the dark rather than the use of RFID that is the solving their problems.

    RFID trends in the future that stand out are:
    1) Conservation of radio spectrum and the efficient use of that spectrum is going to be the most important success factor for the industry. RFID implementation is about increased operating efficiency, and like computers it is going to become more and more the equipment of the workplace. It is therefore critical that the use of spectrum by any individual reader is kept to a minimum so that it can work in harmony with other readers in the vicinity. This requirement is going to mean the demise of high interference protocols such as EPC Global Gen 2 and the need to switch to tag-talks-first type protocols. (A white paper of spectrum use by different protocols is availalble on the website - this paper has already been requested todate by 450 companiies and government regulators).

    2) That the RF power requirements for transponders will continue to fall with developments. Low RF power means a well designed antenna system for the transponder that can couple energy to the RF chip. Low power requirements mean that portable readers can give good operating range, that battery life of such equipment can be reasonable, and that transponders can operate well in a physical situation where they are screened from the reader such as when attached to individual bottles in a crate. To show improvement, a normal dipole attached to a 5 volt circuit needs 54,000 uW of RF power to operate. We now get transponders that use just 200uW of RF power to do the same job, and today we announce a special purpose device that can cut this to 0.3uW

    3)That transponder size will continuously reduce to fit into the requirements of the users to have very sensitive transponders with small form factors. Credit card size is still too big even though it is 50% less than the ideal radio size already.

    4)That RFID will not fit into the major retail applications and that these type of applications cannot become a commercial success for any party. The idea of a very low cost transponder in very high volumes is attractive for the financial press and for the hopes of the end user, but unless the people who are going to put up manufacturing plant to make these items can get a fair price, factories are not going to be built. The scale of the problem to put low cost transponders into retail is so vast that the human mind almost cannot comprehend such a problem. The manufacturing capacity of the world would need to expand 1 million fold and mechanical assembly would become a bottleneck. A state of the art machine for assembling transponders at present can produce about 7 transponders per second, and the market needs one million such machines to meet their requirements for this sector. This lack of enthusiasm by the owners of the factories where such products would have to be produced is reflected in their annual reports where they are regularly closing existing factories and laying off staff.
    It is unfortunate for the RFID industry that the biggest retailer in the world gets an appetite for the product, and that the industry was not given an opportunity to grow in a controlled manner dealing first with high value applications and then move onto the high volume applications.

    5) That the lack of companies with RF and software expertise to customise RFID hardware to the needs of the end user is a major impediment to the realisation of the productivity improvements that this technbology can release. RFID technology is becoming a consumer technology, in the same way that computers or printers have become, being sold off the shelf. They work well in a structured software environment that does not exist in most industries or applications. IT companies that can bring order to the logistics, manufacturing, and service industries are needed so that the productivity benefits of computer techhnologies can be released.

    RFID is here to stay!! Companies that want to advance and stay competitive need to play with this technology to understand the issues and how it will be applied to their needs.

    Getting your own complete RFID/radar system
    You can order RFID systems from Trolleyscan.com

    Trolley Scan also provide a starter RFID-radar system.

    RFID-radar is the next generation of RFID equipment combining identity with position information using the same low-cost transponders.

    The systems comprise a reader, antennas and 20 transponders.

    These systems are already in use in 20 countries.

    To order see
    Order form

    RFID-radar newsletter
    Newsletter No 16

    6 May 2007

    1) Merging of RFID hardware and software to make solutions for applications
    2) RFID Software database solutions for LAN based networks
    3) Expanding software into applications
    4) 24 volt DC kit for readers and radar

    Merging of RFID hardware and software to make a solution for applications
    RFID hardware equipment has evolved into an off-the-shelf technology that anyone can buy in a box and install on their systems. However getting the hardware is only part of the problem to having a successful application. The hardware generates data about items passing in front of readers and it is how that data is handled that determines in most cases whether an application will be successful or not.

    To date the interfacing and software skills required for converting RFID hardware into successful applications was provided by system houses and IT companies that used skilled engineers and scientists. In fact a whole industry has grown around writing Middleware software, software for just converting data from RFID readers into compatible forms for enterprise software - software that often costs more than the total spend on RFID hardware.

    It is time for there to be a revolution in the availability of suitable software for RFID applications!!!

    In the same way that RFID hardware can be bought by any user in a box, the relevant software needs to be similarly provided at low cost so that any user can install systems with minimum technical skills.

    Trolley Scan are delivering on a project to meet all your requirements from a single source as detailed below.

    RFID software database solutions for LAN based networks
    RFID systems identify items by reading a unique number from the transponder attached to that item and retrieving the description of the item from a database. Trolley Scan has developed a new product to meet this function.

    Trolley Scan has already started delivering copies of a new LAN based database system that will retrieve description data from a database and display it on remote computers.

    The system takes data from one or more readers which interface their RS232 data streams onto the LAN via a personal computer on the LAN, or via a new RS232/LAN adapter available from Trolley Scan. This data is retrieved by a LOOKUP program which retrieves that description data from the database and which creates log files. The description is broadcast on the LAN such that any other computer on the LAN can retrieve the data using a DISPLAY program and show the description on its screen.

    As applications grow in size, many RFID readers are likely to be working in unison with the same transponders, for example a production line setup with goods passing reading stations. The above software caters for many readers operating in parallel and for then consolidating all the measurements into a single data stream and database.

    The software provided in the standardised version is in the form of RUNTIME files - just install and use - while the advanced versions also provide source code.

    The software is available immediately from Trolley Scan. Further details are at http://trolleyscan.com/software.html

    Expanding software into applications
    Trolley Scan will be delivering software packages for managing standardised applications using RFID and RFID-radar readers. The intention will be to have low cost packages that fit 90% of the requirements of most applications. The interface files will be standardised and simple to use meaning that the applications can be customised if needed.

    Applications that are on the short list are:
    Access control
    Conference management
    Production line monitoring
    Farm herd management
    Asset management
    Sports timing

    The software will be provided in the standardised version (which is in the form of RUNTIME files - just install and use) or the advanced versions where source code will be provided.

    24 volt DC adapter kit available for RFID readers and RFID-radars
    In order to generate very pure radio frequency signals that will stay within 10kHz of spectrum at approximately 900MHz operating frequency and yet give sufficient power to operate at good ranges, Trolley Scan reader and RFID-radar products operate on 24 volt DC power. This is provided by a mains power supply delivering 24 volts.

    As a result of requests from researchers who wish to use RFID reader and RFID-radar products for research in locations far from mains power, Trolley Scan have introduced a 24 volt kit that can be fitted to reader and RFID-radar products in manufacture.

    The kit allows the equipment to operate either from mains or from 24 volt DC such as from batteries. The kit includes polarity sensing and will not cause any damage to the equipment even if the batteries are incorrectly connected.

    Getting your own complete RFID/radar system
    Like Amazon.com, you can order RFID systems from Trolleyscan.com!!

    Trolley Scan also provide a starter RFID-radar system. The systems comprise a reader, antennas and 20 transponders.

    These systems are already in use in 15 countries.

    To find out details of the system and to order see http://rfid-radar.com/

    RFID-radar newsletter
    Newsletter No 15

    2 April 2007

    Making RFID into a productive technology
    A long time ago printers in computer rooms were specialised items of equipment that needed teams of technicians to service and keep running with regular maintenance shutdowns. Nowadays you buy them off the shelf in the local computer store, plug in to your computer, and even throw away and replace rather than getting them fixed if they ever breakdown. The impact of this progression in printer technology has been that the level of technical skill of the user has fallen so far that when my mother buys a printer for her computer, she does not know even if it is laser or inkjet technology.

    RFID systems capture information from transponders attached to items and relay this information to a computer system for further processing and decision making in a similar manner to the printer receiving information from the computer and printing it on paper. In fact the fitting of RFID equipment to computer systems is very similar to the fitting of printers to computer systems, just at the opposite end of the computer data stream. In the same way that the technical skill of the printer user dropped, so it is happening with the user of RFID systems.

    At the same time there is massive advancement in the performance available from RFID systems with increased range and features, including the ability to locate a transponder exactly as well as read its identity in large spaces. These developments start to strain the abilities of the group in the middle, the software developers who have to take the RFID data and make it into a useful image for the application user.

    The challenge is to simplify the use of RFID such that any farmer, home owner, small business owner, hospital, or the like could use the technology. To achieve this the challenges lie in the software manipulation of the data. Although programming at this level itself is a subject that is taught in most high schools and can be handled by scholars, the challenge is to adapt to the existing software systems of the user and their particular needs.

    Take for example the farmer with a herd of cows. Computer systems can monitor the amount of milk the cow delivers at each milking, its weight and using programs such as that from Cedara, the vitamins and additional salts can be dispensed into the feed for that particular animal depending on its stage in the milk cycle.(I used to manage a herd of 100 cows a long time ago!!).

    With a portable UHF reader, the farmer can, when inspecting the animals in the field, read the identity of any particular animal at a distance of about 10 metres. What one wants to do is present to the farmer immediately on his display attached to the mobile reader, the name of the animal, its date of purchase/birth, its cost, its current weight and how much milk was given at its last milking. To do this the farmer already has all the information needed in many of his databases of the farm, but software is needed to assemble all the required information in a format needed for his decision making.

    The answer does not lie in trying to standardise all farmers on the same software. This would condemn him to the worst of bad choices. The answer lies in simpler interfacing modules and in simpler routines for standardising access to databases so that if there is a new development, say a method of measuring cattle skin texture, it can also be added to the overall software management of the farm even for the smallest users.

    The same problem applies to companies wanting to monitor assets, to stop laptops being removed from buildings, to provide access control systems, to run centralised laundries, to deliver courier parcels and the like. Possibly this software is going to come from the RFID manufacturers rather than the software houses.

    As an example consider interfacing of the hardware. Trolley Scan have in the past (and still do) delivered systems with RS232 interfacing, a standardised 35 year old technology that was available on every PC sold. More recently RS232 has disappeared from the computer and now a USB/RS232 adapter is needed. The advantages of RS232 is that it is an industrial preferred standard, can be used over distances up to 1 kilometre, and can be monitored with very simple equipment. Currently we are preparing an interface box that will convert RS232 to TCPIP so that the readers can be attached to any office internet network, and we are looking at RS232 to Bluetooth for the link from the mobile reader to the PDA display. Besides the hardware challenges of such a move, it brings major software challenges as the data can be delivered anywhere in the world in a fraction of a second(even to your cellphone), but how is it going to travel that last centimetre from the datafile delivered by internet to the input of the application that is going to process the data? Each application has its own challenges and the number and variety of applications that use this data is infinite.

    With TCPIP and the like, destinations are specified by unique IP addresses and Port numbers - how am I going to get my mother to understand how to set those numbers so that she can hook the RFID reader onto her computer? How am I going to tell her how to find the IP address of her own computer? These are not insurmountable problems but illustrate the challenges to moving to simpler interfacing, application software and making RFID a technology that can be used in every home, farm, and small business.

    Getting your own complete RFID/radar system
    Like Amazon.com, you can order RFID systems from Trolleyscan.com!!

    Trolley Scan also provide a starter RFID-radar system. The systems comprise a reader, antennas and 20 transponders.

    These systems are already in use in 15 countries.

    To find out details of the system and to order see http://rfid-radar.com/

    RFID-radar newsletter
    Newsletter No 14

    6 March 2007

    Forthcoming development - credit card sized 35 meter range tag.
    RF power to energise transponders is generally limited to between 0,5 and 2 Watts in most countries by the national regulators. At the same time as RFID reader technology merges into Real Time Locating System(RTLS) technology, the user would like to have longer and longer operating ranges so that they can monitor larger areas with fewer readers.

    UHF frequencies, by the laws of nature, allow long operating ranges with practical antenna sizes. Operating range is a function of efficiency of the antennas which means antenna sizes that will have a dimension of about 16 centimeters at these frequencies which is the half wavelength dimension.

    Trolley Scan are currently testing a new design for a battery assisted credit card sized tag that will operate at 35 meters.

    The new tag is similar to the Claymore tag provided to RFID-radar users in that it contains a fair volume of polypropelene plastic to try to make the transponder more neutral to the influence of being attached to items that they are tagging. Generally items that are in the near field zone of a transponder will influence the performance of the radio waves in the vicinity of the tag and the challenge is to neutralise these effects, while keeping very low operating energy requirements and small size.

    These tags are not active tags in the sense that they do not transmit any signal from the tag. They reflect some of the energy arriving from the energiser of the reader back to the reader at the same frequency. This means that the tags will respond to multiple readers simultaneously and correctly if the readers are operating on slightly different frequencies and are in close proximity to each other.

    This frequency agility property allows many reader systems to monitor correctly the same zone with overlapping fields, and it allows for goods to be tagged in one country and read correctly in another country at a very different operating frequency.

    These tags are still being tested, and will not be supplied with current systems till all hurdles are sorted out. They will be compatible with all existing RFID readers and RFID-radars supplied by Trolley Scan.

    Because Trolley Scan products have a wide range of packaging options and operating sensitivities, they are found in a wide range of applications by users in 49 countries. They operate at long ranges; large numbers of transponders are allowed in a zone; are very fast to respond and allow maximum speeds up to 300kph; and the readers are simple to interface to software. The same transponders will operate with Trolleyponder RFID reader systems if just identification is needed,or with the RFID-radar system if real time locating is needed.

    Users of the technology typically are farmers managing a herd, a vehicle garage managing access for regular clients, a company managing the movement of its laptop computers, a library managing its books and lenders, access control systems for staff, a trucking company monitoring usage of its vehicles, a car hire company checking to see the tyres supplied on its vehicles have correctly been returned, an industrial laundry managing the washing of gowns and overalls for a factory, or even a logistics company managing parcels passing through its warehouse.

    RFID-radar newsletter
    Newsletter No 13

    6 February 2007

    1) White paper on RFID usage of the radio spectrum achieves widespread readership.
    2) Trying to fit many users into a small slice of the radio spectrum
    3) Mixing and matching

    White paper on RFID usage of the radio spectrum with different air protocols.
    In our previous newsletter we announced the availability of a white paper on the usage of the UHF radio spectrum by different air protocols. This is an important issue as, like cell phones, it is expected that there will be an explosion in the number of RFID reader systems in small geographical areas. It is necessary to optimally utilise the minimal radio spectrum allocated for this application efficiently to allow for wide spread usage of RFID and minimal interference between closely located systems.

    More than 200 companies asked for copies of the white paper as a result of the last newsletter. Organisations such as NASA, Boeing, Govt Departments, University Research groups specialising in RFID, Spectrum Regulatory bodies of the various Governments, virtually every competitor of Trolley Scan who manufactures UHF readers and numerous individuals who wanted to understand the issues. In addition three publications asked to publish the full text in their forthcoming editions.

    The document has been written such that novices with little understanding of radio issues can follow the arguments as well as those well-versed in these matters.

    To get a copy in PDF format -(450kbytes)


    Trying to fit many users into a small slice of the radio spectrum
    During the past month, Trolley Scan has been carrying out tests for some of the regulators to measure the impact of RFID on spectrum usage. The issue is that a narrow slice of spectrum is being allocated in most countries for RFID which has to fit between other important users such as GSM cell phones. Unfortunately the ideal UHF frequency for RFID is in the 860MHz to 960MHz band which also is the ideal frequency for other communication applications, meaning a crowded spectrum at these frequencies. If one can find 2MHz of spectrum available in this region in most countries one is very lucky.

    In one case, the regulator has the requirement that the spill-over of energy out of the RFID band into the adjacent band, must be less than 110dBc, that is, one hundred thousand million (1 with 11 zeroes) times less than the peak energy of the RFID reader. With low modulation rates of the reader energising signal this is practical, but EPC readers will find it very challenging.

    Mixing and matching
    Historically there has been little interest in pushing the operating range of passive RFID beyond 15 meters. One does not want to be scanning the contents of one room and end up documenting the contents of the next room unbeknown as the radio signals pass through physical barriers such as walls. The arrival of RFID-radar encouraged the development of longer operating ranges as both the identity and the location of items were reported. From Trolley Scan came stick tags and claymore tags that could be read from more than 40 meters away even with just 0.5 watts of RF power. These tags reflect the energy from the energiser back to the reader, so it is possible by defining the energising beam to define a reading zone and not activate the tags if they were not in that area. (This is similar to the problem of RFID charge cards at petrol stations where control is needed on the operating zone so that the right card gets charged for the added petrol, and not the card that has the strongest signal!)

    Recently Trolley Scan have been asked to deliver an RFID system to monitor the identity of trucks being loaded by an operator working a loader who is 40 meters away from the trucks. This application requires that only the truck being loaded is identified as against other trucks in the facility or waiting in the queue. This is not a problem that can be solved with the conventional active tag, as although the active tags have good range, there is no discrimination with physical location.

    The components between Trolley Scan's RFID reader and RFID-radar systems are interchangeable. By using the standard RFID reader module with the high gain antennas from the RFID-radar system and the very sensititive Claymore tags, Trolley Scan can define the reading zone to just be around the truck that is being loaded 40 meters away and ignore all others in the facility.

    RFID-radar newsletter
    Newsletter No 12

    2 January 2007

    A prosperous and successful 2007 to all our readers!

    During the Christmas holidays an important research project was completed on looking at the use of the very limited radio spectrum by RFID applications. Unless something is done, RFID will strangle itself by being wasteful with the precious spectrum resource.

    1) White paper on RFID usage of the radio spectrum with different air protocols.

    White paper on RFID usage of the radio spectrum with different air protocols.
    Radio Frequency Identification uses part of the radio spectrum for its operation. This is a precious resource as the available spectrum is limited, in some countries more than in others. As more and more users will want to use this technology as it increases in popularity, so the demands on the spectrum will escalate.

    By careful selection of the optimal air protocols between the reader and the transponders in the RFID system, many users can share the available spectrum.

    This paper shows measured results of the different spectra of the different protocols using advanced spectrum analysers and signal generators.

    These results allow an understanding of the issues involved and indicate why a change from certain protocols that are currently promoted needs to be made as the industry matures.

    The document has been written such that novices with little understanding of radio issues can follow the arguments as well as those well versed about these matters.

    To get a copy in PDF format -(450kbytes)


    Getting your own complete RFID/radar system
    Like Amazon.com, you can order RFID systems from Trolleyscan.com!!

    Trolley Scan also provide a starter RFID-radar system. The systems comprise a reader, antennas and 20 transponders.

    These systems are already in use in 15 countries.

    To find out details of the system and to order see http://rfid-radar.com/

    RFID-radar newsletter
    Newsletter No 11

    21 November 2006

    1) Going underground
    2) Standardising the manufacture of readers and radars
    3) How does RFID-radar measure the distance so accurately?

    Apologies for sending out this newsletter so late. We have so much news about ongoing developments that we aim to produce a newsletter each month. However we received so many orders for our Readers and RFID-radar systems that we did not dare write a newsletter in case others also placed orders. Now three months later, we have had so many clients ask why they have not received their newsletter that we feel compelled to bring you up to date.

    Going underground
    UHF transponder systems such as our Ecochip technology, offer long reading ranges and form an ideal input system to a computer network. Trolley Scan have recently supplied a third consignment of readers and tags to our clients for use in mining operations underground, particularly in the control of heavy machinery in situations where the machinery must not be operated when people are close by. Other uses are to computer control the progress of moving machines in close environments and make sure the movement happens safely. As the transponders are passive - offering 100 year type lifecycle - low maintenance systems can be installed. With their very narrow spectrum bandwidth, their low power and their low interference technology for the readers, many readers can operate in close proximity without causing interference. At present this is an adaptation of equipment used above the surface and is not suitable for use in coal mines and those that need intrinsically safety due to our use of materials such as aluminium in the antennas of the reader.

    Standardising the manufacture of readers and radars
    As a technology finds acceptance, the challenge moves from making something work to producing it in volume at lower costs. Currently Trolley Scan provide RFID reader systems to users in 49 countries and RFID-radar systems to users in 20 countries.

    Due to similarities in the design of our standard reader (which just gives identity), and the RFID-radar which gives (identity and accurate position) - while both working with the same series of passive low power transponders and battery assisted long range tags; Trolley Scan have developed a new processor module that is very suitable for use in both projects and which can be assembled at speed with modern pick-and-place equipment. This development allows more of the systems to be built by sub-contractors at higher volumes. Both systems also use the same RF power amplifiers as they both are very narrow band, low interference systems allowing many readers to operate continuously in close proximity.

    Recently Trolley Scan had an opportunity to compare how advanced is its technology compared to many of the UHF RFID systems that are being used in the retail systems. These retail systems have such poor RF performance that their antennas need to be mounted very close to the doorways restricting the traffic through the opening. This is because their read distances are so small that they are just about competitors for conventional barcoding systems. These systems also have a poor air protocol that uses a lot of bandwidth and stops other users operating similar equipment in the vicinity - having to resort to a sharing of the spectrum by listening for others before being able to operate.

    If you want to have a successful system for the retail type project, then you are going to have to

    1. have systems that use very little operating power for their transponders as this power has to come from the reader,
    2. that give good read range,
    3. that give good penetration of the goods being scanned so that you can read transponders on the inside of the pallet,
    4. that use very little radio spectrum so that many users can operate in a close space without interference,
    5. whose readers can operate continuously on their narrow spectrum at doorways so that goods cannot slip past while the reader is off air,
    6. that it is able to detect fast moving items,
    7. whose readers are able to process close and far transponders at the same time catering for their large difference in signal levels.
    These unfortunately are not typical of the characteristics available from many of the retail systems currently under test and highlight the difficulty of showing large improvement over their much cheaper barcode technology equivalents.

    How does RFID-radar measure the distance so accurately?
    The radar makes two measurements on each signal received from each transponder in its receiving zone - namely a range measurement and an angle of arrival. It is the ability to measure range with narrow bandwidth that make this an outstanding unique RFID instrument. The system uses the same transponders that are used by conventional RFID readers allowing RFID-radars and RFID readers to monitor the same transponder simultaneously.

    Light and radio waves travel at the speed of light, namely 300 000 000 meters per second. RFID systems need to operate in a crowded RF spectrum, where other RFID systems, cell phones, radio stations and other communication users have to share the available radio spectrum. RFID-radar uses just 10 kilohertz of bandwidth to operate, meaning it can detect time differences only as small as 0.1 milliseconds, or 0.0001 seconds. In this time the radio wave will travel 30 kilometers, or 30 000 meters or 3 000 000 centimeters. Yet the radar is able to determine the range of the transponder based on its received transmission to an accuracy of a few centimeters, or nearly 1 million times better than its basic time measuring properties. If we used a conventional military radar approach and wanted to get centimeter precision, then we would have to measure the time of flight to 0.3pico seconds (.3*10-12) which would use 300GHz of radio spectrum and ensure that no other radio users can operate in the vicinity.

    RFID-radar pays for this million times improvement in the timing accuracy of the basic system by taking a longer time to determine the exact position. As a result it is well suited to a static situations where transponders are relatively stationary. However developments are in progress to address the accurate tracking of movement by adapting some of the principles of operation.

    The angle of arrival measurement is virtually instantaneous and used in conjunction with range gives a 2D positioning system from a single measuring location.

    Getting your own complete RFID/radar system
    Like Amazon.com, you can order RFID systems from Trolleyscan.com!!

    Trolley Scan also provide a starter RFID-radar system. The systems comprise a reader, antennas and 20 transponders.

    These systems are already in use in 13 countries.

    To find out details of the system and to order see http://rfid-radar.com/

    RFID-radar newsletter
    Newsletter No 10

    24 August 2006

    1) Speed kit for Radar
    Speed kit for Radar
    The examples above describe applications of Trolley Scan's RFID reader technology. Trolley Scan have also developed an RFID-radar technology which gives the identity and the location of many transponders in a reader zone at one time. RFID-radar is a new technology that uses the same transponder technology as the older RFID reader systems, but which encourages new challenges due to its greater performance, challenges such as increased operating range (40 to 100 meters), more accurate position information (already millimeter precisions are possible) and accurate tracking of fast moving items. RFID-radar is now in use by clients in 13 countries, clients who are typically University research organisations, motor vehicle manufacturers, mining companies wanting monitoring of positioning of heavy equipment, logistic companies, bioscience research groups studying the interaction of a population of animals, military research organisations and IT companies that want access to the latest technologies. As with all Trolley Scan products, the systems are low bandwidth low interference systems that allow many systems to operate in close proximity.

    RFID-radar was initially developed to accurately position tags in a static situation. Users have requested that we expand this to track fast moving items accurately. As a result of a study of this situation, we have found that the challenge lies in the overloading of the RF protocol between the transponders and the reader, rather than issues inside the reader.

    Trolley Scan are providing three speed transponders in their kit with current purchases. These speed transponders fully utilise the capacity of the RF protocol available with this system. Software is still being developed for the speed applications, but these additional transponders will allow existing owners to fully test the capabilities of their systems when updated with later versions of the software.

    RFID-radar newsletter
    Newsletter No 9

    1 July 2006

    1) The next issue is tracking accurately items moving at speed
    2) Low weight transponders for animal tracking
    3) Upgrading systems

    The next issue is tracking accurately items moving at speed
    Just over six months ago, an invention that allowed the measurement of the distance a signal travelled accurately from a low cost transponder to the reader was discovered. This invention changed the potential that users could expect from low cost RFID systems as position information could now also be reported with identity information. In this time, the invention has been packaged into a form for commercial use and supplied to users in many countries.

    RFID-radar was initially developed to monitor static situations where there is no movement between the transponders and the readers during measurement. Although initial versions were specified for 0.5 meter accuracy, the system has been refined to provide centimeter and millimeter accuracy.

    Clients have requested that the abilities of the system be improved to monitor moving transponders also with the same precision and this is the direction of the current research.

    The conventional RFID readers that are supplied by Trolley Scan to users wanting fast movement - such as sports timing, can handle speeds up to 300kph. However the radar needs to lock onto the signal from each transponder in order to measure location and has a completely different challenge for speed.

    At present the radar uses a measuring stick of approximately 7.1 centimetres. To measure the speed correctly, the reader needs to receive valid codes from transponders at time intervals such that at least two valid measurements are received during the travel of 7.1 centimetres. This restriction limits the number of transponders that can be in the field at the time the speed measurements are made, as each uses up some of the capacity of the single communications channel between the reader and the multiple transponders for sending its data.

    At present a single transponder (special type) can be tracked at 51kph, if there are two then the speed drops to 8kph, four at 3kph etc.

    Trolley Scan have a project to look at this limitation by introducing time as a dimension to the reader and applying curve fitting techniques. Other routes might be to shorten the data stream from the transponders.

    When the version that can handle many transponders at higher speeds is ready, software updates will be available to all RFID-radar owners.

    Low weight transponders for animal tracking
    RFID-reader and RFID-radar systems comprise transponders and readers. The readers radiate a low power, typically 0.5 to 2 watts which provide an energising field and set the carrier frequency for communication data between the reader and the transponders.

    Trolley Scan provide a range of transponders, from 200uW credit card sized Ecochiptags, Ecowoodtags, Ecosportags, and laundry tags to stick tags and top of the range Claymore tags. The sensitivity of these tags varies from 1000uWs to 0.3uWatts depending on construction and sophistication. The Claymore tags use a large block of plastic (118cu cms) to focus the energy onto the sensor and give a tag that is independent of influence from the goods to which they are attached. Depending on which tag one chooses, one gets different operating ranges from the low power energy of the Reader.

    All these transponders operate in a mode where they reflect received energy from the reader back to the reader. This means that the tags themselves do not radiate any energy, and that they will respond in situations where they are in overlapping coverage zones to many readers/radars simultaneously, with the correct information allowing them to be positioned and identified without being influenced by more than one reader/radar covering a zone. They also will respond to radars/readers over the whole 100MHz UHF RFID spectrum needed for international compatibility.

    The radar has stimulated interest from a University project where they would like to locate accurately the current location of small mammals. Here we need long range, but a small light weight transponder. Unfortunately the antenna length is set by the operating frequency which means the need for a thin wire antenna but the transponder needs to be small and yet lightweight so as not to overload the mammal. Trolley Scan have developed a very small transponder that can be used in this application and yet is very lightweight, having just three small chips on the transponder to provide all communication features over long ranges.

    In order to keep at the fore-front of the RFID UHF technology, Trolley Scan continually develop and improve their products, sensitive to the needs of their clients that they want their equipment always to be up to date with the latest performance.

    Trolley Scan have just upgraded some of the very first RADARs that were bought to the latest DSP versions of the technology, to bring the equipment on par with the current generation. This upgrade now allows the clients to receive future upgrades in the pipeline via software modules without the equipment needing to be returned.

    RFID-radar newsletter
    Newsletter No 8

    13 June May 2006

    1) Newly developed special patch antenna for RFID-radar
    2) RFID-radar achieves millimeter precision
    3) One family of equipment

    Newly developed special patch antenna for RFID-radar
    Once again, technical advancement with RFID-radar in the past month has been rapid!! As with all new technologies, the first stage in development is to get the system working and proven, and then comes the fine tuning and the manufacturing issues.

    In developing the RFID-radar, Trolley Scan had hoped to use the same patch antennas that are used in our very successful UHF RFID reader which is used in 46 countries. Unfortunately the results achievable with the standard patch antenna was not encouraging, and the antenna system was changed to be one based on a 6 element Yagi design.

    The reason for the change was not one of getting a high gain to get a long range, but rather the need to have a well defined phase centre for the antenna so that it could be used for precise measurement. RFID-radar measures the distance the signal travels from the transponder to the reader and to achieve this measurement accurately delays in the reader system need to be known accurately.

    The Yagi antennas were bulky, being about 0.8 meters long and were cumbersome to mount. However their phase definition is vastly superior to that of the conventional patch design. The first RFID-radar systems were therefore supplied with Yagi antennas designed and built by Trolley Scan.

    Trolley Scan's search for a replacement for the Yagi antennas achived success a few months ago when an antenna with reduced size and which improved the professional appearance was discovered.

    A very special patch-like antenna, measuring just 30 cm by 30 cm by 3cms was found that has a well defined phase centre. Initially these patch-like antennas were only available for US frequencies, but recently a special version has been produced to operate at the EU frequencies. This was a major hurdle as Trolley Scan clients are distributed across the different frequency bands and we did not want to get into the situation of supplying some with the new patch-like antennas and others with Yagi antennas due to the different operating frequencies.

    From the beginning of June, all clients have been receiving their RFID-radars with the new patchlike antennas. These antennas are tested on positioning multiple Claymore type transponders at ranges up to 40 meters and are suitable for indoor/outdoor use, being suitable for mounting on any flat structure, such as a wall.

    More details can be found at http://www.rfid-radar.com

    Millimeter precision achieved with RFID-radar
    RFID-radar has the ability to measure the radio path length a signal from the tranponsders has to travel to the reader. It does this measurement using just 10 kilohertz of bandwidth.

    Recent focus at the request of clients has been to improve the accuracy of the system from the approx 0.5 meters error in 100 meter range for specific applications.

    For applications like the auto focussing of cameras in movie set applications, Trolley Scan have developed a high precision mode for detecting relative movement of objects, achieving precision approaching one millimeter accuracy in movement for targets up to 40 meters from the reader. The radar is able to track the relative movement of multiple targets at one time, and the reporting mode has been adjusted to report on millimeter changes rather than the centimeter reporting used for the normal mode.

    The rate at which the reader reports current positions has also been increased by option to report up to 100 transponder positions per second to the host computer.

    One family of equipment
    Trolley Scan provide a range of compatible readers,radars and transponders.

    This family of equipment has a characteristic of very low power efficient UHF transponder technology , which means long operating ranges, fast responses and low power RFID readers and RADARs.

    Transponders are available in different forms depending on range needed and pricing.

    Different types of transponsders are 200uW credit card sized Ecochiptags, laundrytags, Ecowoodtags, Ecosportags, stick tags and Claymore type transponders. All of these will operate over a 100MHz operating spectrum if needed (frequency agility), use backscatter modulation and low interference Tag-Talks-First technology.

    Trolley Scan provide UHF fixed readers, UHF portable readers, UHF OEM readers, UHF RFID-radar readers and OEM RFID-radar readers that are compatible with the above transponders depending on the clients needs. These readers use just 10 Khz of bandwidth, can be set to operate at any of the global UHF RFID frequencies from 860-960 MHz (actual frequency depends on country), and source between 0.5watts and 2 watts of RF power depending on needs of the client.

    RFID-readers can handle up to 800 transponders in a zone at a time with speeds up to 300kph, while the RADARs will give accurate location information for up to 50 transponders in a zone at a time at low speeds. Due to low spectrum utilisation, multiple readers and radars can operate in close proximity with minimal interaction.

    These are truely the RFID technologies of the future!!!

    RFID-radar newsletter
    Newsletter No 7

    10th May 2006

    1) RFID-radar morphs from experimental to commercial status
    2) Information presentation
    3) Interesting uses of RFID-radar
    4) Merging of RFID and RFID-radar technologies to become the future reader technology?
    5) Finding a partner to supply high volumes of cheap RFID-radar systems

    RFID-radar morphs from experimental to commercial status
    Once again, technical advancement with RFID-radar in the past month has been rapid!! As with all new technologies, the first stage in development is to get the system working and proven, and then comes the fine tuning and the manufacturing issues.

    A bottle neck in the number of targets that could be ranged and accurately tracked at one time had been caused by the computer doing the final number crunching stage, although it was done in an efficient compiled language code running on a fast Pentium processor with a minimal operating system.

    The past month has seen this part replaced by the very latest in Digital Signal Processing technology running an Assembler code that has been optimised for the architecture of the new processor.

    The result is that the radar now can make more than ten thousand (10 000!!) range calculations on transponders in its zone EVERY SECOND - a 500-fold increase in processing capacity over its predecessor. The position accuracy of the radar has also shown a ten fold improvement, with accuracies of a few centimeters and pointing accuracies of small fractions of a degree over the 100 meter operating range of the radar. Further there have been cost reductions and the change has resulted in a much simpler system to manufacture.

    The end result is that we have a very impressive, accurate measuring and data capture sensor for connecting to an IT system front-end for sophisticated applications.

    Trolley Scan are now supplying this as a commercial version that can be used in everyday applications. We also have an OEM version that can be incorporated into clients' projects. Systems can be ordered directly from Trolley Scan - more info at


    Information presentation
    The RFID radar reports the identity, the range and the bearing from the reader, for every transponder, once per second. This generates a large amount of data and we have developed some novel filtering algorithms to reduce the data.

    The first is a version called SLICE. Here the radar only reports transponders that are within a band of values of the range from the reader - for example between 35 meters and 45 meters. A typical application here might be monitoring a herd of cows where you are only interested in those cows that are wandering near the boundary fence. A similar situation might be monitoring supermarket trolleys usage in a parking lot and not wanting them to be removed from the lot.

    The second data filtering is called WHERE. Here an individual transponder identity can be tracked from the multiple transponders that are in the reader zone, and just its location will be passed onto the host computer at regular intervals.

    The third is called DUMPRATE and allows the reporting rate for all modes to be set at any time interval between one and twenty seconds.

    In all cases, the radar measures the range up to 10 000 times per second, but passes the latest value when the display criteria are met.

    Interesting uses of RFID-radar
    When RFID-radar was first proposed as a viable technology, Trolley Scan believed that an accuracy in range measurement of 0.5 meters would be achievable. Later developments have now improved this to about 2 centimeters.

    Trolley Scan have been asked to investigate if the range accuracy can be improved further to millimeter precision. Driving applications for such accuracy are the automatic focusing of cameras on movie sets where the radar can continuously monitor the distance to a transponder on the actors person providing accurate focussing commands to all participants in the film scene.

    Another possible application of millimeter accuracy RFID-radar technology is in the monitoring of the position of storage boxes in a specialised storage location where robots can be instructed to fetch the correct box based on its current location.

    It would appear that special versions would allow the extension of the RFID-radar accuracy to millimeter precision, even over the 100 meter range, in future applications.

    Merging of RFID and RFID-radar technologies to become the future reader technology
    On analysing the structure of an RFID-radar system and a conventional RFID system, one notices many similarities and it is clear that the technologies are very close, despite the one only giving identity and the other giving exact position and identity.

    This similarity is so strong, that we have provided a software setting on the Radar that can switch the system into RFID mode as against the normal RADAR mode.

    In RFID mode, the reader will report the arrival of any new transponder into its scan zone, even if that transponder is moving at 300kph. It will not again report the identity of that transponder, until such time as it has left the reader zone and returned. Depending on the transponder type, this can be a zone currently as deep as 40 meters from the reader. By switching back to the RADAR mode the location of all the transponders is once again reported repeatedly.

    Although the radar is more complex than a conventional reader, with increased volumes and manufacturting advances, the price of the reader should fall to close to that of conventional readers in the medium term. Then the situation will be reached where one would wonder why conventional RFID readers are still being produced. Would the market still want to purchase a reader if it could only read identity compared to one that could read identity and exact location for the same price?

    Finding a partner to supply high volumes of cheap RFID-radar systems
    Trolley Scan is a small innovative company based in South Africa. It is a world leader in UHF RFID technology with a proven track record currently providing systems to users in 46 countries.

    Together with its RFID-radar and other innovative products such as long range low power transponder technology (Ecotag), it has stimulated exponentially increasing demand for its products.

    The time might be right for Trolley Scan to partner with a large scale high volume manufacturer of RF products with an established distribution network, who would be interested in supplying the needs of this high volume, insatiable market.

    RFID-radar newsletter
    Newsletter No 6

    17 April 2006

    1) Interesting uses of RFID-radar
    2) Better than a tape measure!
    3) Claymore tags
    4) Free paper on the choice of frequency

    Interesting uses of RFID-radar
    Trolley Scan provide very advanced transponders and reader systems. The focus has been on getting long range, multiple transponders, fast response, low noise, multiple readers in close proximity and simple technology to use. Now Trolley Scan have started delivering their latest world leading development - RFID-radar(tm) - a technology which not only gives identity, but also very accurate position measurement of all transponders in a very large zone. This invention has led to the need to extend the range of operation from a reader, and operating distances of 40 meters are now achievable.

    Since delivering the first few RFID-radar systems to clients in Europe, Trolley Scan are getting interesting feedback from potential users of this new technology.

    Some interesting potential applications of this technology in the past few weeks have been:

    1. Tracking continuously the location of 20000 people in a skyscraper using multiple RFID readers and RFID-radars, wanting position accuracy at any time to a few meters.
    2. Monitoring the use and location in an open air parking and loading bay of a public utility by tracking the instantaneous location of 500 vehicles, using a cascade of up to nine RFID-radar systems.
    3. Monitoring the location of a number of participants at close range as part of a work study.
    4. Monitoring multiple works of art in a museum in an open space by measuring the exact range between the RFID-radar and the transponder once per second to great accuracy.

    It will be interesting to see the growth of applicatons of this technology in the future.

    "Better than a tape measure!"
    The accuracy of the range measurement ability of the RFID-radar continues to amaze!

    The RFID-radar system has been designed to operate with the same series of transponders as the RFID readers, to operate with the same spectrum requirements, to operate such that many RFID-radars and Readers could work in close proximity at one time - and generally be 100% compatible with the existing UHF reader technology.

    Despite these physical restrictions, the measuring ability of this new technology has continued to cause surprise.

    RFID-radar measures directly the distance the signal travels from the transponder to the reader. It does not use issues of how energy decays as it travels; it does not use a mapping system to show power levels available in the zone from multiple transmitters; it does not use local hotspots of energy such as Wi-Fi systems; it does not use any form of triangulation; and it does not use African witchcraft! It measures the actual distance travelled - be it in a line of sight or even if the energy has to pass through an obstruction, such as a wall.

    When Trolley Scan launched the concept and built the initial system, our tests indicated that a target of 0.5 meter accuracy would be achievable out to 100 meters. We continue to improve the technology with ongoing developments, and tests over Easter have shown we will be able to offer centimeter-precision shortly, with possible millimeter accuracy later this year. This precision will be on transponders operating at distances up to 100 meters.

    Based on this high degree of precision from a simple RFID based system, Trolley Scan have trademarked the phrase

    "Better than a tape measure!"

    to describe this excellent potential. Measuring accurately with a tape measure over 100 meters is a challenge, but the RFID-radar can do the same task once per second for many transponders in a zone at the same time.

    We regularly update results on our website and if you refer to the page "White paper on measurement results" at


    it will show recent developments. In this paper we provide a panoramic image of the placement of transponders together with the data displayed on a map as measured. We have mounted a cluster of transponders nearly 40 meters away and show results on how the RFID-radar is able to resolve their individual positions.

    Claymore tags
    When RFID transponders are attached to an item, the presence of that item close to the transponder can have an influence of the performance of the transponder and thereby on the performance of the RFID system. Generally range measurement for development is made in perfect conditions, and this performance has to be downgraded when the transponder is applied in real life. Trolley Scan have addressed that situation in the past with products such as Ecowoodtag, a transponder that gives excellent range when attached to a wooden item, but poor range if it is measured just in air.

    The transponder has to collect energy from the energising field of the reader and reflect some of that energy back to the reader. Generally the transponder's radiation pattern is uniform in all directions around its axis.

    When a tag is attached to a major object - like a railway container - then no energy can pass through the object, meaning that one does not need the transponder radiation pattern to be uniform around the axis as half of it is screened by the container.

    Trolley Scan have developed a new series of transponders called Claymore Tags. These are directional transponders, made to be attached to large objects and where they will always be read from one side. They comprise a specially designed plastic block with appropriate air spaces, which acts in a similar manner to that of a lens for an optical system, focussing the incoming radio energy onto the transponder, and then directing the reflected energy back towards the reader.

    The use of this design means that much greater transponder sensitivities can be achieved with much greater ranges, and the transponder's performance will be the same no matter to which item it is attached.

    Free white paper on choice of frequency
    RFID systems from all manufacturters around the world operate in one of a number of predefined frequency bands. The choice of the frequency band impacts the operation of the RFID system due to the laws of physics. The choice of operating frequency is the most important choice a user of RFID technology needs to make.

    Trolley Scan have recently written a white paper on the subject discussing these choices. A free copy will be sent to you by following the request below.


    The paper does not just cover Trolley Scan products, but covers the 125kHz, 13.56Mhz, UHF and microwave bands.

    RFID-radar newsletter
    Newsletter No 5

    15 March 2006

    RFID-radar systems on their way to IT clients in Europe
    It is vary rare that the same person will be involved two major breakthroughs in the field of RFID!!!

    In 1990, Mike Marsh invented the protocol called Supertag which was demonstrated by scanning a supermarket trolley filled with goods, each of the goods labelled with a transponder. These demos were seen by 300 million viewers of 650 TV stations at the time of making the demo public. In addition 2000 companies contacted us wanting to be involved, and maybe 500 attended a live demo.

    It was amazing to push a loaded trolley with 38 items through a scanner, and see all the items instantaneously listed on a screen as the trolley passed through at speed.

    The RFID-radar has turned out to be a similar experience!

    The challenge is to measure the location of transponders at a distance from a reader - i.e how far did the signal travel from the transponder to the reader and what was the angle of arrival. All this needs to be done in an environment when many RFID and RFID-radar systems are going to be sharing the same spectrum, where the radio energy path is confused by reflections (multipath) which cause uncertain signal strength information, where there are many transponders in a zone at one time, and where one would like to use very low cost transponders at distances up to 100 metres.

    The experience with RFID-radar is impressive!

    The RFID-radar system is turned on with many transponders scattered in a zone up to 40 meters from the reader. Immediately the display reports the identity of all the transponders in the zone, all at a fictitious range entry location. About twenty seconds after start up, the display changes instantaneously to show the range and bearing to all the transponders in the zone, with their positions being plotted accurately on the display. From then on movements of the transponders are plotted and positions are updated.

    Readers of this newsletter will have followed progress of this new RFID technology, since the discovery of a method to accurately measure the range of transponders just 6 months ago in August 2005. A few months later we reported on early testing of the concept while developing an Evalution model, to a major 14000 measurement test last month.

    We can now report that the first IT companies in Europe that asked for the technology are being supplied with systems operating at low power on 869.5Mhz

    This has been a major achievement, in that in a very short time, we have had to build repeatable production modules for the hardware, to write programs for the four parallel computer modules in the radar, write demonstration programs for the user to use on the display of data, and write handbooks for the users.

    RFID-radar changes the RFID landscape as it encourages the development of longer range RFID systems. As you now know the position of the low cost transponder, you can have one RFID-radar system scanning much bigger areas than with the conventional RFID system as you will be given the exact coordinates of the parcel/package/container/cow.

    For example if you had a conventional RFID system with a range of 100 meters, you would only know that somewhere in the area in front of me, the size of a soccer or rugby field - lies my parcel. With RFID-radar you know its location to 0.5 meters. That difference means that RFID systems will most probably only max out in range at 10 meters while RFID-radar systems will max out at 100 meters - separating the functionality in applications of the two systems.

    The RFID-radar has a major additional advantage over any competitive RTLS systems, in that it measures from a single point without needing preplanned infrastructure, such as needed with triangulation systems. This means you could in theory fit an RFID-radar system to the front of a forklift truck, and drive it around showing the location of all goods relative to that forklift truck. (We even have been asked to fit it to a helicopter!!)

    The road ahead for RFID-radar is going to be long. The current version provides a vehicle to which many features will still be added over the next few years, thereby increasing the functionality of this new technology.

    Increasing the operating range
    Over the past few weeks Trolley Scan have been experimenting with parameters that impact the operating range of the RFID-radar. In the past at shorter ranges, virtually any receive antenna would handle the requirements of collecting signals from transponders at a distance.

    We have found that at longer ranges, the important issue is the receiving antenna rather than the transmitter antenna or power. With very good receiver antennas, we are able to fix the location of low power backscatter tags at distances as far as forty meters even with only 0.5 watts of transmitter power. The receiving antennas needed are the equivalent of high performance 10 element Yagis, able to collect the very weak signals reflected off the backscatter tags and which signals have then dissipated in the 40 meter travel back to the reader.

    Trolley Scan are not offering these antennas yet as part of the standard package, rather supplying more reliable 6 element antennas at a slight loss of range.

    However we intend to provide the better antennas as an upgrade at some later stage.

    Ordering a system
    A brochure detailing the performance of the current systems now being delivered is at


    and order form to buy a system is at


    RFID-radar newsletter
    Newsletter No 4

    8 February 2006

    14000 Test results confirm accuracy of RFID-radar
    Every once in a while, some single graphic/image sums up progress with a technology in one concise statement.

    We have known with RFID-radar that we can measure range while using minimal bandwidth, low cost transponders, a speed of propagation of radio waves of 300 000 km/sec, a time piece with a resolution of only 0.1 milliseconds (during which time the radio waves travel 30 kilometers!), and low energiser RF power. However we did not know how accurate and repeatable those measurements would be?

    On the 23rd January we measured the location of two transponders, one at 10 meters and one at 43 meters. We measured the range once per second for four hours, or fourteen thousand independant measurements - and we plotted them on the display!!

    These tests showed a variation of an amazingly small 1 meter in range over those fourteen thousand measurements - really quantifying how well this system of measurement can work; and how RFID-radar will in the future be able to provide the core component of the next generation of UHF RFID systems.

    A PDF document with the results of the tests and discussing increasing the range towards 100 meters is at


    RFID-radar newsletter
    Newsletter No 3

    19 January 2006

    Trolley Scan add a 49 meter range tag to product list
    In December-January, manufacturing in the Southern Hemisphere is usually interupted which allows the staff of Trolley Scan focus on new product development. In our past newsletter, we announced that deliveries of the RFID-radar would commence at the end of January, which had been delayed by software and art progress. We also in this time have developed a very low power transponder that can be supplied with the radar and even with the ordinary RFID reader if needed.

    How much range does one need for an RFID system?

    Trolley Scan have in the past supplied their 200uW Ecochiptag with a 13 meter operating range. The key distance for RFID readers seem to be about 6 meters as since the RFID energy penetrated walls and floors you do not want to read the contents of the adjacent room when scanning assets; a ceiling mounted reader can read all goods passing through the doorway/passageway; and goods that you are reading are directly in front of the reader. As we have increased the range with technology inprovements, so we have reduced the energising power (down to between 0.5 and 3 watts) and we have widened the coverage field of the antennas.

    The arrival of the RFID-radar, with its ability to measure range and location change the requirements. There seems to be interest in having working ranges as far as 100 meters for each radar as the goods are located by their position data meaning it is easier for the operator to find the specific item.

    Trolley Scan announce the development of a 5 microwatt transponder that is compatible with its readers and the RFID-radar. With an improved antenna system this tag has been measured at a distance of 49 meters from the reader. With conventional antennas, it operates at 25 to 30 meter range. The tag is compatible with all the other tags and readers provided by Trolley Scan and can be used with the RFID-radar and with its portable and fixed readers. The tag is freuency agile, and will operate at all frequencies between 860Mhz and 960Mhz, needing just 5uW of RF power in its 134 to 149 sq cm aperture. The tag is a backscatter tag, generating no interference and operating on the Trolleyponder(RIST) protocol.

    In order to get this superior performance,this tag is no longer a single chip solution meaning that it is at a higher cost that the standard 200uW credit card versions.

    All deliveries of the RFID-radar system will include five of these transponders with the 20 Ecochiptags for evaluation and software development by clients.

    Later this year,clients will be given the option to order more sophisticated antenna systems to extend the operating range of this tag from 25/30 meters to 49 meters on just 2 watts of transmitter power.

    RFID-radar newsletter
    Newsletter No 2

    4 January 2006

    This is the second newsletter detailing developments to keep interested parties up to date with progress.

    In August 2005 Trolley Scan announced the invention of an RFID technology that could measure location and identity of cheap transponders. In this newsletter we announce the availability of systems that clients can now order.

    You are receiving the newsletter as you indicated that you either
    1) wanted to buy a prototype system
    2) wanted to buy a commercial version
    3) wanted to use OEM modules in your own products
    4) wanted to be sent the newsletter.

    RFID-radar(TM) technology becomes a reality
    RFID-radar(TM) is a new technology that was developed by Trolley Scan (Pty Ltd in South Africa at the beginning of August 2005. It allows a computer network to identify and locate continuously many cheap transponders in a zone with high accuracy.

    In our past newsletter we announced that we had tested the principles of accurate range measurement and were targeting the delivery of the first systems in January 2006. Having worked flat out through the past months and the festive season, we have now developed a package of an RFID-radar system with supporting transponders and software that we will be able to start supplying in late January 2006. This is our "prototype" version. This version has the performance of the future versions but uses more expensive parts than we expect to use in the commercial versions, and has computing capabilities only for a limited number of transponders being processed simultaneously.

    Those who purchase this version will be able to evaluate the technology and start developing software solutions to interface to the RFID-radar and applications. Purchasers will be able to upgrade to the latest version at anytime for a nominal charge, meaning that this equipment will not become obsolete due to further developments.

    Trolley Scan have created a web page at


    where details of the package are provided, together with results from the latest tests and graphics showing the output of the sample software that is provided with the system.

    The site also contains an order form where you can place a non-binding order for the system and get into the waiting list for delivery. When Trolley Scan have cleared the backlog above your position in the queue and are in a position to supply your system within a few days, they will contact you and verify that you still want to purchase a system.

    RFID-radar newsletter
    Newsletter No 1

    14 October 2005

    RFID-radar(TM) is a new technology that was developed by Trolley Scan (Pty Ltd in South Africa at the beginning of August 2005.

    This is the first newsletter detailing developments to keep interested parties up to date with progress.

    You are receiving the newsletter as you indicated that you either
    1) were interested in the entire technology package
    2) wanted to buy a prototype system
    3) wanted to buy a commercial version
    4) wanted to use OEM modules in your own products
    5) wanted to be sent the newsletter.

    By receiving this newsletter we are acknowledging that you have been added to the RFID-radar newsletter distribution list.

    What is RFID-radar
    RFID-radar is an amazing invention from Trolley Scan where a "simple" RFID-reader can:-

    1. Identify multiple transponders in a reader zone
    2. Provide range information to locate those transponders to an accuracy of approx 0.5 meters
    3. Provide direction information to identify the direction of the transponder to an accuracy of about 1 degree
    4. Can track movement of transponders as they cross the zone.
    5. Can predict the path of transponders when they are temporarily screened from the reader (say passing behind a steel door)
    6. Can track the movement of a large number of transponders simultaneously.
    7. Operates at any of the UHF frequencies allocated for RFID in most countries i.e at any frequency from 860 to 960 Mhz
    8. Uses just 10 kHz of bandwidth with low modulation levels allowing many radars to operate in close proximity.
    9. Uses simple passive or active transponders.
    10. Uses very low RF power, from as low as 0.5 watts
    11. Can sweep a range up to 100 meters depending on transponders and configuration.

    Progress in the past month
    When we first discovered the principles that allowed us to measure the range of a transponder ten weerks ago, we immediately constructed a prototype based on laboratory equipment and desktop computers. The results of the tests of that configuration were shown on our website(www.rfid-radar.com) when we first mentioned the developments to those users who receive the Trolley Scan newsletter (We still have to do the press announcements!!). We were using a fullsize 2.45GHz Pentium to perform the calculation and reduce the data from the sensors, oscilloscopes and large screens. This setup enabled us to quickly verify our theories and to show what sort of performance could be expected.

    Our immediate goal is to shrink the volume of the reader so that we can fit it in a standard Trolleyponder reader case which we can then supply to those wanting prototype systems.

    We have in the past month advanced significantly the development of a single board 2 channel receiver that collects the required data and takes up the volume of a single reader in the RFID reader system. This combining of channel receivers is important to give pointing accuracy during movement of transponders in a zone, as when each reader makes a measurement of range at a slightly different time, it causes an error in the pointing accuracy while that transponder is moving. As soon as the transponder stops moving, then the direction information is correct. By combining the receivers, we will hopefully fix this annoying issue.

    We have replaced the 2.45GHz Pentium, display, keyboard etc, with a single board embedded processor that performs the complex difficult calculations and outputs the identity of the transponder, and its location at regular intervals. We have also developed the software for these units so that the RFID-radar will function in a standalone mode with no opeator needed.

    We have broken up the radar system into a standalone radar processor section and a display section. This enables simple processing in the display section such as can be implimented on a laptop.

    Photos of the radar with its seperate display are shown at http://www.rfid-radar.com

    How does RFID-radar compare with RFID readers
    RFID readers such as our Trolleyponder/Ecotag system are the basic work horse of the automatic identification industry. When a transponder comes into the reader zone, the reader reports the presence to the computer network which implements algorithms to decide on what action needs to be taken. The transponders arrival is only usually reported once, and the transponder has to leave the zone before it is read again. Although Trolley Scan offer already ranges of 13 meters in air and 10 meters in metal, this is most probably the furthest range that users need for practical systems. Improvements in transponder sensitivity with time will now translate to reduced reader powers, longer batter life in portables, and wider coverage from the antennas. RFID readers will form the bulk of the Auto ID Industry.

    RFID-radar reports the identity of transponders entering its zone as quickly as that reported by the RFID readers. Thereafter they locate the transponder and provide location and tracking information at regular intervals (say once per second). This deluge of data requires a more sophisticated upstream processor for interacting with the user, a processor that will interpret the movement of all these transponders and for example trigger an alarm if a transponder goes into a restricted area. This will result in the RFID-radar being provided in more expensive, sophisticated applications than those for the RFID reader and will result in a whole new class of applications and possibilities than what can be achieved with RFID today. RFID-radar benefits from range increases due to transponder sensitivity. We have initially targetted maximum ranges of 100 meters as a practical goal.

    What can be done to fasttrack your involvement.
    UHF RFID systems that operate over extended distances have certain characteristics that need to be understood. Examples are "holes" in the energy field, the correct mounting of transponders, the mounting of transponders on metal objects, and the processing/interfacing of the data. We strongly recommend companies first experiment with normal UHF RFID readers, such as our Trolleyponder/EcoTag system, before taking on the higher level complexities of an RFID-radar system.
    To get a small RFID reader starter system look at http://trolleyscan.com/

    Trolley Scan (Pty) Ltd © / info@rfidradar.com