Channel-Aware Line Code Decision in RFID

In the RFID system, far field passive tags send information to the reader using back scattering. The signal strength of RFID tags is much smaller than that of a reader. So the channel condition significantly affects the tags' identification performance. Although there are 4 line codes in EPCglobal C1 G2, how to decide an appropriate line code is not specified. If the line codes can be adaptively decided by the channel condition, the performance of identification is increased. In this paper, the authors propose a novel line code decision protocol to measure the channel conditions and adaptively change the line code at every slot.