Timing-Aware RFID Anti-Collision Protocol to Increase the Tag Identification Rate

Radio frequency identification (RFID) technology is one of the most popular systems to uniquely identify items by attaching a tag to them. The growing number of tagged items that need to be identified in one reader interrogation area leads to high tag collision rates. Therefore, fast anti-collision protocols are required to minimize the total tags identification time. Fast protocols involve a high tag identification rate (TIR), defined as the number of tags identified per time unit. In this paper, a thorough study of TIR is provided, analyzing the main factor which affects it: the frame size update strategy. Applying the conclusion of this analysis, the anti-collision protocol Timing-Aware Frame Slotted Aloha (TAFSA), is presented to increase TIR. TAFSA presents a timing-aware frame, because its size is set according to the timing parameters of a real RFID system based on the current standard. The performance of the proposed protocol is evaluated and compared with several state of the art Aloha-based anti-collision protocols. Considering a typical RFID scenario, simulation results show that TAFSA, with an average of 56.7 tags identified per second, achieves a 10% average improvement in TIR in relation to the strategies of the comparison.