Active RFID System With Spread-Spectrum Transmission

In this paper, we propose a new direct-sequence code division multiple access (DS-CDMA)-based transmission scheme for active, transmitter-only radio frequency identification (RFID) tags. We present the architecture of the system, as well as the mathematical analysis of detection performance and system capacity. Because of the good multiple-access properties of DS-CDMA transmission, the proposed system outperforms the classical ALOHA-based RFID system with transmitter-only tags. The obtained analytical results have been verified via computer simulations. Some implementation issues have also been discussed.