The passive RF identification system is discussed in this paper. The system uses the surface acoustic wave (SAW) as an identification tag and works at ISM-915 MHz. The system adopts a pair of passive dispersive SAW filters for pulse expansion and compression in order to improve antijamming performance and degrade the severe requirement for sensitivity of a wideband receiver. Then, the structure of the SAW tag, the principle of transmitter and receiver, and the DSP subsystem are discussed. Finally, testing results are demonstrated.
