一种基于捕获效应的防碰撞算法设计

Design of an Efficient Anti-Collision Algorithm Based on Capture Effect

捕获效应在无线通信系统中非常普遍。在无源射频识别系统(RFID)中,由于捕获效应的存在,即使读写器范围内多个标签在同一时间反向散射信号给读写器,总有一个标签能够被成功识别。提出了一种新颖的防碰撞算法来提高RFID系统的吞吐量。该算法在帧时隙ALOHA协议的基础上考虑了捕获效应。在捕获模型下,提供了待识别标签数的概率性估计方法和捕获效应敏感的最佳帧长度的推导。理论分析和仿真结果显示,提出的算法性能超过了现有的算法,而且降低了计算复杂度。

Capture effect is very common in wireless communication systems. In a passive radio frequency identification （RFID） system, even though multiple tags baekscatter their signals to a reader simultaneously, one of the tags will be successfully identified due to the capture effect. A novel anti-collision algorithm is presented to increase the throughput of RFID system, which considers the capture effect on the context of framed ALOHA protocol. Under the capture model, the probabilistic method for estimating the backlog （ number of tags waiting to be identified） and the derivation of the capture-aware optimum frame length equation are provided. Theoretical analysis and simulation results show that the proposed scheme not only outperforms the existing algorithms in identification performance, but also reduces the computational complexity.