A Novel Fast Tag Estimate Method for Dynamic Frame Length Aloha Anti-Collision Algorithms in RFID System

In an Radio Frequency Identification (RFID) system, Dynamic Frame Length Aloha (DFSA) has been widely used in anti-collision protocol due to its high efficiency. A fast and accurate estimate of tag population is critical to the performance of DFSA. In this paper, we propose a closed-form tag estimator which reduces greatly the computational complexity while maintains high accuracy. Also we propose a two-step estimate method which can further improve the estimate performance. Simulations show that the error of proposed tag estimator is less than 4%. Furthermore, the proposed tag estimator has significant advantage in lower complexity over existing estimate methods.