无源RFID自适应帧时隙防碰撞算法研究

射频识别RFID作为一种重要的物联网终端数据采集技术，系统的吞吐率直接影响着数据采集终端的性能，但目前广泛应用于无源RFID系统的帧时隙类防碰撞算法吞吐率普遍较低.本文着重分析了影响无源RFID帧时隙类ALOHA防碰撞算法性能两类因素：帧长和碰撞时隙的处理方式，通过构建和求解帧长调整和标签碰撞的数学模型，给出了无源RFID帧时隙类ALOHA防碰撞算法的具体优化途径和方案：帧长自适应调整和碰撞实时散列.在此基础上提出了自适应二进制散列帧时隙ALOHA防碰撞算法-ABSFSA.实验结果表明ABSFSA算法在同等条件下可以有效减少无效时隙，明显将RFID系统的吞吐率稳定提高到45%.本文的研究工作为无源RFID帧时隙类防碰撞算法的优化提供了可供参考的数学模型，同时对提升物联网数据采集终端的性能具有一定的应用价值.

Research on Passive RFID Syste m Adaptive Frame Slot Anti-collision Algorithm

As an important data acquisition technology,throughput of RFID system affects performance of the data ac-quisition terminal of Internet of Things directly,but the throughputs of passive RFID system anti-collision algorithms of framed slot are generally low.Two factors influencing throughput of RFID systems are analyzed,which were frame length and the way of solving collided slots.Mathematical models of frame adjusting and tag collision are set up and solved,and then a solution is proposed for optimizing the anti-collision ALOHA algorithms of framed slot,that is,frame length adjusting adaptively and collision binary splitting timely.On these bases,the adaptive binary splitting frame slotted ALOHA anti-colli-sion is constructed.The simulation results show that ABSFSA algorithm is able to decrease the invalid slots effectively in the same condition,and the throughput of RFID system is steadily improved to 45%obviously.The research work provides a re-ferable mathematical model for optimizing the anti-collision ALOHA algorithms of framed slot,and a valuable solution for improving performance of data acquisition terminal of Internet of Things.