Abstract: ALOHA anti-collision algorithm is an important RFID anti-collision algorithm in RFID （Radio Frequency Identification）. The algorithm is simple and easy to implement, but the system throughput is low. The algorithms of ALOHA （DFSA） algorithm are studied and improved. In this paper, the ALOHA algorithm and its improved algorithm are summarized in detail. The current research method is deduced and experimentally simulated. In this paper, the algorithm of key link tag estimation algorithm for Dynamic Frame Slot ALOHA （DFSA） algorithm is carried out and concluded detailedly. Finally, the current research direction is put forward according to the present situation.

Key words: ALOHA, Radio Frequency Identification（RFID）, anti-collision, tag

摘要： ALOHA防碰撞算法是无线射频识别技术RFID（Radio Frequency Identification）中一种重要的标签防碰撞算法，该算法设计简单，容易实现，但系统吞吐率较低。其算法不断被研究改进，针对ALOHA算法及其改进算法加以详细的总结，对现在的研究方法加以理论推导、实验模拟，其中对动态帧时隙ALOHA（DFSA）算法中关键环节标签估计算法进行详细归纳。最后结合如今现状提出下一步研究方向。

关键词: ALOHA, 无线射频识别（RFID）, 防碰撞, 标签