ABSTRACT
Radio frequency identification devices (RFIDs) have been used widely in industrial and medical applications. Specifically, RFIDs have been applied in asset tracking and security systems by several companies extensively. RFID can store and retrieve data using RFID tags/transponders remotely. The conventional RFID system includes tags, reader, local software/infrastructure, and back-end system. RFID tag is the identification device in the system and contains at least a microchip attached to an antenna that sends data to the RFID reader. The antenna emits radio signals to activate the tag and to read and write to it. The signal strength depends upon the power output. When the RFID tag passes the electromagnetic zone, it detects the reader’s activation signal. The reader decodes the data encoded in the tag’s integrated circuit (IC) and passes it to host the computer for processing as shown in Figure 7.1. RFID tags can be active, passive, or semipassive tags. Active RFID tags are powered and as a result, require continuous power for operation. These types of tags have better communication distance. Semipassive tags use power for internal tag circuitry; however, they establish communication using the RF signal energy. Passive tags completely operate and communicate based on the energy of RF signal and hence very limited communication distance. Basic block diagram of RFID system. https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9781315217123/13a58586-a36e-44a5-a930-490b7cf9fbae/content/fig7_1.tif"/>
