多个应答器的碰撞问题是影响超高频射频识别(RFID)系统读取效率的一个关键问题。从EPC Class1 Generation2 (C1G2)RFID系统帧长受约束特点出发， 分析了帧时隙ALOHA防碰撞机制及其经典应答器估计方法的特点。提出了应答器间隔估计方法(IEM)以及基于该方法的EPC C1G2 RFID防碰撞算法，并给出了仿真结果。与现有基于经典应答器估计方法的射频识别系统防碰撞算法相比较，提出的防碰撞算法减少了识别时间， 提高了系统的识别效率。-Multiple transponder collision issue is the ultra high frequency radio frequency identification (RFID) system, read the efficiency of a key issue. From the EPC Class1 Generation2 (C1G2) RFID system fr a me length bound characteristics of the analysis of fr a me-ALOHA anti-collision mechanism and the classic estimation methods transponder characteristics. Proposed transponder interval estimation method (IEM), and based on the method of EPC C1G2 RFID anti-collision algorithm and gives the simulation results. With the existing estimation methods based on classical transponder radio frequency identification system compared to anti-collision algorithm is proposed anti-collision algorithm to reduce the recognition time and increase the efficiency of the system identification.