An efficient anti-collision protocol for tag identification in RFID systems with capture effect

RFID tag identification is one of challenging issues since the simultaneous transmissions in the shared wireless medium cause collisions between the replies. Many anti-collision protocols have been proposed to resolve this problem by detecting the collisions so that the tags are identified. However, the capture effect inhibits the collision detection, since the reader regards the collision as a successful transmission instead. In the paper, we show that Collision Tree (CT) protocol suffers from the capture effect. We then propose a Multi-Round Collision Tree (MRCT) protocol which successfully identifies all the tags within the reader´s coverage.