| Home - Glossary - Radio Frequency IDentification (RFID) |
Related expressions
RFID Transponder, RFID Tag,
RFID reader,
Transponder applicator
Explanation
Radio Frequency IDentification (RFID) is a technology with numerous usages for real-time typically wireless item identification. RFID tags can be attached to virtually any item eg. luggage, goods, containers, products, pallets, trucks, cars, keys and animals. The most common application consists of 2 parts:
- a transponder, or “tag” which is a microchip with an antenna
- a reader, or “transceiver” (a computer with an antenna)
The microchip in its simplest form contains a unique number, which is the transponder’s identity. Radio Frequencies are used to transfer information (at least the identification number) between the transponder and the transceiver. To transfer information between the reader and the transponder, the reader emits radio waves that activate the transponder and the transponder use energy to transmit information to the reader. If the transponder utilises the operating power from the signal transmitted by the reader, the transponder is called passive. If it possesses an extra power source such as a battery it is called an active or semi passive transponder.
The transponder modulates, i.e., changes the radio signal before re-transmitting it back to the reader. The information on the microchip (the identification code) is transferred wirelessly via this re-transmitted signal as the data is coded to the signal (Figure 9). The microchip in its simplest form contains a unique number, which is the transponder’s identity. More advanced microchips can contain additional information.
Figure 9 : The basic principles of Radio Frequency Identification
Several systems operating at different frequencies are used: e.g.
- low frequency (LF),
- high frequency (HF)
- ultra high frequency (UHF).
At LF an electric field can be used to transfer the information between the transponder and the reader. This transfer is called capacitive coupling between the transponder and the reader. The range for this connection is very short. The field strength decreases rapidly when the distance between the transponder and the reader is increased.
Alternatively, a magnetic field can be used with so-called inductive coupling at LF and HF. This allows a longer reading range up to even one meter. At UHF, radiated electromagnetic waves (radio waves) can be used which increases the reading distance up to 10 metres in optimal conditions.
Application/Usage in Indisputable KEY
Automatic tracking of wood in the complete forest-wood chain (from the forest to the wood products manufactured in the various industries) may have different outputs: facilitating the implementation of a chain of custody, but above all the understanding of relations and correlations existing between the raw material characteristics and the final product qualities.
The UHF region will be used in the Indisputable KEY project because the long reading distance is essential for logistics and forestry applications. The reading distance can be increased by:
- increasing the amount of energy emitted by the reader,
- increasing the size of the antenna for the reader and the transponder,
- decreasing the power needed for the transponder to operate and/or increasing the sensitivity of the reader so that weaker signals transmitted by the transponder can be detected,
- decreasing the losses in the system so that energy can be utilised more efficiently.
Some of the remaining challenges for the project are:
- to test the possibilities of RFID-technology in automatic tracking applications within forest industry
- to enhance the knowledge on RFID antenna,
- to develop automatically applicable robust RFID-transponders, as well as a novel disturbance tolerant RFID reader with high reading accuracy that can be integrated in forest machines.
- Some of the drivers and barriers for utilizing this technology in the forest industries are described in deliverable D-3.1 – Initial analysis of drivers and barriers.
Institutions with teaching capabilities
RFID Lab in Finland is a Finnish application center for RFID technology, especially focusing on logistics systems. RFID Lab Finland offers neutral information, consulting, training and measuring services to the interested parties in Finland.
In England, the RFID Centre offers one-day training courses held at Bracknell training facilities. The courses are aimed at staff from the same company, group, or members of a trade association and typically comprise between 6 and 24 attendees. They can concern : RFID Technology & Standards Basics, RFID Fundamentals for IT Professionals, RFID Fundamentals for Supply Chain Professionals, Assessing Business Value and ROI for RFID, RFID Pilot and Implementation Planning. See
RFID4U (Canadian) offers various RFID training courses worldwide (USA, United Kingdom, Turkey, Ireland, Canada, Taiwan, Singapore, Poland, Germany and others) in a variety of formats (including e-Learning and instructor-led training).
Available text books and training material
White papers: “
A Basic Introduction to RFID Technology and its use in the Supply chain
“, 2004.
“
RFID Essentials
”, Bill Glover, Himanshu Bhatt, 2006 : drawing on extensive experience, Bill Glover and Himanshu Bhatt provide in this book essential information on this emerging technology. They give information and understanding to start designing, building, or integrating with RFID systems. There are information on: Tags and tag protocols, including the Electronic Product Code (EPC).
See also :
http://www.rfidjournal.com
http://www.teamrfid.com
