A Transponder Anti-Collision Algorithm Based on a Multi-Antenna RFID Reader

Radiofrequency identification has emerged a lot of applications where object identification is necessary. This technology seems to be, unlike traditional object identification, the optimal solution to achieve a contactless transfer of information between a reader (interrogator) and tags. Where the reader attempts to identify more than one tag in its interrogation area, this situation may lead to a collision resulting that messages will cancel each other. In this paper, we propose a scenario where collision probability is reduced due to a mechanism allowing tagging to track activities on the communication channel. Furthermore, the proposed solution explores both time (time slot) and spatial (multi-antenna) domains. Part 1 introduces to RFID technology and tag collision problem. Some existing solutions are discussed at part 2, and finally at part 3, comes the main idea of this paper: we present the algorithm and the advantage of the use of a multi-antenna reader.