RFID Reader Receivers for Physical Layer Collision Recovery

Abstract--Arbitration and scheduling of multiple tags in stateof-the-art Radio Frequency Identification (RFID) systems is accomplished on the medium access control layer. Currently, only answers of a single tag can be decoded in such a system. If multiple tags respond simultaneously, a collision occurs. In that case, conventional systems discard the physical layer information and a retransmission is executed. This work shows how to recover from such collisions on the physical layer and successfully read the data. The contributions of the paper are: 1) An analysis of the achievable throughput increase of a system, that can recover from collisions at a physical layer is given. 2) A model for a description of collisions on the physical layer is presented. 3) Based on this model, we propose a channel estimation method and two types of receiver structures for separating the signals of a collision of two tags: first, single antenna receivers that discriminate the sources of the two tags in t...

• Type: Journal
• Year: 2010
• Where: TCOM
• Authors: Christoph Angerer, Robert Langwieser, Markus Rupp
• Keywords: Collision, Physical Layer, Software Engineering, Tags, TCOM 2010