中文摘要：

为进一步提高射频识别阅读器的标签识别效率，提出一种按需时隙分配高效防碰撞协议．该协议将识别循环分为预约帧时隙阶段和在帧时隙内读取标签两个阶段，通过帧前预约机制消除读取阶段的空闲时隙，采用预约冲突捕获机制有效地减少了读取阶段的碰撞时隙数．在此基础上，通过选择最优预约时隙随机码位数和最优预约时隙数，实现了该防碰撞协议的识别效率最优化，分析了该协议标签电路复杂性，并给出了适用于本协议的标签数估计方法．性能评估表明：该防碰撞协议的平均识别效率达到91.28％，在通信复杂性和识别速度方面明显优于现有典型防碰撞协议．

英文摘要：

In order to further improve the identification efficiency of the Radio frequency identification （RFID） system ,an efficient anti-collision protocol based on on-demand slot assignment is proposed .In this protocol ,each identification round is divided into two steps including reservation stage and identification stage .The proposed protocol avoids collision frame slots and empty frame slots by the capture mechanism of reservation collisions and by the reservation mechanism of frame slots ,respectively .Fur-thermore ,the optimal bit number of reservation random code and the optimal number of reservation slots are given for obtaining the optimal efficiency .The paper analyses the circuit complexity of tag based on the protocol ,and proposes the tag estimation method suitable for the protocol .Performance estimation shows that the average efficiency of the protocol is about 91.28% and it signifi-cantly outperforms the existing anti-collision protocols in terms of communication complexity and identification speed .