RFID Passive Readers

Radio-frequency identification (RFID) is a technology that uses electromagnetic fields to identify and track objects that have tags attached to them. A tag is a small device that contains a radio transponder, which can send and receive radio signals. When an RFID reader, which is a device that emits an electromagnetic pulse, comes near a tag, the tag responds by sending back digital data, such as an inventory number, to the reader.