RFID collision signal separation on physical layer for Pseudo-random ALOHA

In the passive UHF RFID system, the traditional label anti-collision method using random multiple access, mainly in the medium access control (MAC) layer, the recognition efficiency is not high. In order to improve the recognition efficiency, the tag anti collision algorithm in some physical layer is proposed. The method directly from the signal recovery tag signal. In order to improve the efficiency of radio frequency identification tag identification. This paper use a method of cross layer separating labels. Storage the total number of conflict tags and the information of tags, placed into a matrix. Be recognition into the next frame, according to the label in the second frame have been identified, to return to the previous frame and the conflict of time slot, Separating the conflict signal on the PHY layer, the recognition efficiency can be greatly improved because the collision slot is not considered as an invalid time slot.