Trolley Scan(Pty) Ltd
RFID-radar(tm)
Trolley Scan(Pty) Ltd
RFID-radar(tm)
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RFID-radar newsletter Newsletter No 19 9th September 2008
Contents
Future advancements in RFID applications 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 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.
Getting your own complete RFID/radar system 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
RFID-radar newsletter Newsletter No 18 1 September 2007
Contents
Monitoring the integrity of bridges and large 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. 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
Contents
Major technical achievement - a small form tag with a long range 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 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 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: 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. 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 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
RFID-radar newsletter Newsletter No 16 6 May 2007
Contents
Merging of RFID hardware and software to make a solution for applications 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 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
Applications that are on the short list are: 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 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 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 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 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. 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
Contents
White paper on RFID usage of the radio spectrum with different air protocols. 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) mailto:info@trolleyscan.com?subject=White_paper_on_spectrum_usage
Trying to fit many users into a small slice of the radio spectrum 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 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.
Contents
White paper on RFID usage of the radio spectrum with different air protocols. 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) http://trolleyscan.com/whspectr.html
Getting your own complete RFID/radar system 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
Contents 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
Standardising the manufacture of readers and radars 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
How does RFID-radar measure the distance so accurately? 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 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
Contents 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
Contents
The next issue is tracking accurately items moving at speed 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 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.
Upgrades 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
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Newly developed special patch antenna for RFID-radar 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 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 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
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RFID-radar morphs from experimental to commercial status 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 http://www.rfid-radar.com
Information presentation 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 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 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 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
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Interesting uses of RFID-radar 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:
It will be interesting to see the growth of applicatons of this technology in the future.
"Better than a tape measure!" 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 http://www.rfid-radar.com 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 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 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. http://trolleyscan.com/whfreq.html 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 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 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 http://www.rfid-radar.com/brochure.pdf and order form to buy a system is at http://www.rfid-radar.com/eval/frmorder.html
RFID-radar newsletter Newsletter No 4 8 February 2006
14000 Test results confirm accuracy of RFID-radar 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 http://www.rfid-radar.com/howgood.pdf
RFID-radar newsletter Newsletter No 3 19 January 2006
Trolley Scan add a 49 meter range tag to product list 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.
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RFID-radar(TM) technology becomes a reality 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 http://www.rfid-radar.com/eval/index.html 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.
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What is RFID-radar
Progress in the past month 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-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.
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