An efficient tag anti-collision protocol for RFID systems

In low-cost RFID systems, efficient anti-collision protocol of passive tags is very desirable for fast identification. In this paper, we propose a new anti-collision protocol: assigned tree slotted aloha anti-collision protocol. The key technology is to assign prefixes to each frame and slot respectively such that tags can match the frame recognition first and slot recognition next. Compared with the conventional Aloha one, the new protocol is deterministic so that it can recognize all the tags. There are fewer collision slots, and shorter delay in our protocol in contrast to others. Most notably, the simulation result shows that our protocol can achieve a system efficiency of 61.8% at most, which is much higher than other protocols.