What is a reader or interrogator?
The reader is an electronic device that communicates with the RFID tag via radio waves and passes the information in digital form to a computer system. Since the reader contains an active radio frequency transmitter, the operating parameters are regulated by the Federal Communications Commission in the United States and similar agencies in other countries. These regulations dictate the operating frequency or fingerprint of the radio signal and the effective radiated power of the readers active transmitter. There are several allocated bands or ranges in the RF spectrum where RFID readers are allowed to function. Some of these frequencies or radio bands vary by country. It is essential that the operating frequencies of both the reader and tags match. In addition, the reader contains circuitry to manage tag data collisions and sorting functions to single out a specific tag in a larger population being read and present that information to a host computer. Each of the specific RFID radio ba
