A Slot-Wise LMMSE Estimate Algorithm for Frame Slotted Aloha Protocol of RFID System

Frame Length Aloha (FSA) is a popular anti-collision protocol in Radio Frequency Identification (RFID) system for its simple and efficient. A major factor which effects the performance of FSA greatly is the estimation of tag population. In this paper, we propose a Slot-Wise tag estimator which can estimate the tag population slot-by-slot and its closed form is derived. Simulations show that the error of proposed tag estimator is less than the existing ones especially when the number of slot observed is small. The proposed estimate can be used in in-frame adjustment scheme to efficiently improve the throughput of the FSA system.