wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

9-2 Industrial Communication Systems
• Electronic drug pedigree
• Anticounterfeit bank notes
• Secure passports and visas
• Anticounterfeit automobile parts
9.2 rFID Architecture
RFID system is composed of the following main elements: tags, readers, antennas, and middleware [EAS05,
MS08]. A typical RFID system is shown in Figure 9.1. When the RFID tag comes in the range of the reader,
the reader activates the tag to transmit its unique information. This information is propagated to the RFID
middleware, which appropriately processes the gathered information and then updates the backend database.
9.2.1 rFID Tags
An RFID tag is a microchip attached with an antenna, which is attached to a product that needs to be
tracked. The tag picks up signals from the reader and reflects back the information to the reader. The
tag usually contains a unique serial number, which may represent information such as a customers’
name, address, etc. [RFID06]. A detailed classification is discussed next. RFID tags can be classified
using three schemes. First, the tags can be classified based on their ability to perform radio communication:
active, semiactive (semipassive), and passive tags. Second, the tags can be classified based on their
memory: read only, read/write or write once, and read many. Finally, the tags can also be classified based
on the frequency in which they operate: LF, HF, or UHF.
9.2.2 rFID Readers
The RFID readers send radio waves to the RFID tags to enquire about their data contents. The tags then
respond by sending back the requested data. The readers may have some processing and storage capabilities.
The reader is linked via the RFID middleware with the backend database to do any other computationally
intensive data processing. There are two different types of RFID readers [GLOE05]. RFID
readers can be classified using two different schemes. First, the readers can be classified based on their
location: handheld readers and fixed readers. Second, the tags can be classified based on the frequency
in which they operate: single frequency and multiple frequency.
9.2.3 rFID Antenna
In RFID, antennas are classified into RFID tag’s antenna and RFID reader’s antenna [POT07].
RFID Tag Antenna: This type of antenna is the conductive element that enables the transmission of data
between the tag and the reader [RFGA06]. Antennas play a major role in deciding the communication
RFID tag
Reader
RFID
middleware
Backend
DB
FIGURE 9.1 RFID architecture. (From Potdar, V. et al., Automated Data Capture Technologies: RFID, Zhang, Q.
(Ed.), Hershey, London, U.K., pp. 112–141, Information Science Reference.)
© 2011 by Taylor and Francis Group, LLC