|Radio Frequency Identification (RFID)
– Identification of packages
RFID is a transponder technology which is set to play an increasingly important role in the field of logistics alongside existing automatic identification systems such as barcodes.
RFID transponders are already in successful use for identifying animals and containers, as part of access control systems, in vehicle immobilizers and in automated production.
But the retail and service industries as well as procurement, production and distribution logistics see extended fields of application being opened up by RFID technology, bringing with it greater efficiency in monitoring and controlling supply chains, whether it be in the reduction of stock levels, the optimization of just-in-time processes, the regulation of traffic control systems in ports and airports, the tracking of shipments or in the monitoring of mechanical or climatic influences on goods during shipment. It is assumed that the greatest potential will be in those sectors that have the highest demands on quality and process reliability, such as the pharmaceutical, chemical and automotive industries.
Unlike with barcodes, RFID transfers data between for instance a package (equipped with a transponder) and a data capture unit (reader) with no need for contact or a direct line of sight. It is also possible to capture the data from several different data carriers simultaneously and to read the information through a range of different materials. Furthermore, the data can be tracked in realtime in defined areas.
RFID is based on electromagnetic waves with frequency ranges from long wave through to microwave. The technology involves a data capture unit or reader reading the data from a transponder (data carrier with an integrated antenna – also known as a "tag") and/or writing new or additional data to the tag.
Figure 1: Schematic representation of RFID technology
Depending on the field of application and the tasks to be performed, a distinction is made between more or less high-performance systems (low-end through high-end). These are characterized as follows:
|Location of the reader:|
|Storage technology of the reader or transponder:|
|Multiple access method of the reader (simultaneous identification):|
|Transponder power supply:|
|Passive transponder (power is supplied by the reader)|
|Active transponder (has its own power supply, is activated by a signal from the reader)|
|Semi-active transponder (has its own power supply used only for data retention)
|Plastic or glass containers / tubes|
|Card transponder – contactless chipcards|
|Resilient metal transponders|
|Typical frequency ranges / fields of application:|
|Low-frequency 125 through 134 KHz –> animal identification, vehicle immobilizers, chipcards|
|High-frequency 13.56 MHz –> access systems, container identification, theft surveillance, package, mail and baggage logistics|
|Ultra-high-frequency 433, 868 or 915 MHz –> automation, production logistics, goods tracking and identification|
|Microwave 2.45 or 5.8 GHz –> tracking/identification of goods, containers and packages, electronic seals, toll systems, fleet management
|Close-coupling – low-frequency up to 30 MHz –> up to 0.01 meters|
|Remote-coupling – less than 135 KHz –> up to 1.5 meters|
|Remote-coupling – 13.56 MHz (proximity) –> 0.1 meters|
|Remote-coupling – 13.56 MHz (vicinity) –> 0.5 through 3 meters|
|Long-range – 433, 868 pr 915 MHz –> 0.5 through 50 meters|
|Long-range – 2.45 GHz –> 10 through 100 meters|
|Long-range – 5.8 GHz –> 10 through 1,000 meters (under development)
Development of RFID systems suitable for deployment internationally faces some considerable problems as a result of disparate frequency regulations and the transmitting power of the reader. It is not only that the frequency bands have been allocated differently in different countries; the permitted transmitting power for the reader also varies, which means that identical models can differ considerably in their range. The frequency ranges up to 135 KHz and 13,56 MHz are generally regarded as having been largely standardized. The standardization process for the remaining frequency ranges is being carried out on the basis of the ISO/IEC 18000 standards published in 2004 (see below).
Details on frequencies, data transfer rates, protocols and encoding are laid down by ISO. To date, the following standards are available:
|ISO/IEC 15693, Identification cards – Contactless integrated circuit(s) cards; vicinity cards|
|ISO 14223, Radiofrequency identification of animals – Advanced transponders|
|ISO/IEC 14443, Identification cards – Contactless integrated circuit(s) cards; proximity cards|
|ISO/IEC 18000-1, Information technology – Radio frequency identification for item management – Part 1: Reference architecture and definition of parameters to be standardized|
|ISO/IEC 18000-2, Information technology – Radio frequency identification for item management – Part 2: Parameters for air interface communications below 135 kHz|
|ISO/IEC 18000-3, Information technology – Radio frequency identification for item management – Part 3: Parameters for air interface communications at 13.56 MHz|
|ISO/IEC 18000-4, Information technology – Radio frequency identification for item management – Part 4: Parameters for air interface communications at 2.45 GHz|
|ISO/IEC 18000-5, Information technology – Radio frequency identification for item management – Part 4: Parameters for air interface communications at 5.8 GHz (withdrawn)|
|ISO/IEC 18000-6, Information technology – Radio frequency identification for item management – Part 6: Parameters for air interface communications at 860 MHz to 960 MHz|
|ISO/IEC 18000-7, Information technology – Radio frequency identification for item management – Part 7: Parameters for air interface communications at 433 MHz|
The use of RFID systems also has attendant problems in that transponders can be removed, deactivated, eavesdropped, blocked, jammed or manipulated and that the readers can be manipulated. Various security concepts such as identity checking, shielding and encryption are designed to virtually eliminate the risk of unauthorized access to tags or readers.
Detailed information on the fields of application and the development perspectives for RFID can be found in the paper "Security Aspects and Prospective Applications of RFID Systems" published by the German Federal Office for Information Security (BSI) at www.bsi.bund.de.
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