Efficient time-oriented anti-collision protocol for RFID tag identification

RFID technology is widely used in number of fields, including supply chain management, industry control, ticket services, human and animal management, and elderly health care services. Accelerating tag identification is an important issue in RFID systems. A series of anti-collision protocols, adaptive binary splitting (ABS), single resolution blocking (SRB), and pair resolution blocking (PRB), has been proposed to solve this problem. However, these protocols still waste much time, since they do not consider the identification delay that is the total time for identifying all tags rather than the number of slots. Thus, this paper proposes a novel protocol, symbolic SRB (SSRB). SSRB inherits the essence of SRB/PRB that reserves the information of the last identification process and adopts the same blocking technique. SSRB further considers the identification delay to allow each recognized tag to respond with a symbolic response, which is a shorter message, instead of its complete ID. Considering different lengths of slots, SSRB further determines the optimal number of initial slots to minimize the identification delay. Also formal analysis of SSRB identification delay with considering different slot lengths is derived. The analytic models and simulation results show that SSRB obtains superior performance than ABS, SRB, and PRB.