A MAC scheduling algorithm of the RFID reader system using multiple receiving antennas

In this paper, we propose a Medium Access Control (MAC) scheduling algorithm to efficiently recognize multiple tags in 900MHz Ultra High Frequency (UHF) Radio frequency identification (RFID) reader, when using multiple receiving antennas. According to the timing of received signal of each antenna, the standard of signal priority is changed to the entering order of the received each signal or the higher value of the Signal to Noise Ratio (SNR). Using additional processing in MAC layer with multiple receiving antennas, it can accelerate the recognition speed of tags comparing with by using current standard based on single antenna. It is possible to free reader to tag interference comparing with by using multiple readers. It is also possible to be compatible with current standard.