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Purpose The purpose of this paper is to study how to improve the performance of RFID robot system by anti-collision algorithms. For radio frequency identification (RFID) robots operating in mobile scenes, effective anti-collision algorithm not only reduces missed reading but also enhances the speed of RFID robots movement. Design/methodology/approach An effective anti-collision algorithm is proposed to accelerate tag identification in RFID robots systems in this paper. The tag collisions in the current time slot are detected by a new method, and then further resolve each small tag collision to improve system throughput, rather than the total tags number estimation. After the reader detected the collision, three different collision resolution methods were described and studied, and the situation of missing tag caused by reader moving is also discussed. Findings The proposed algorithm achieves theoretical system throughput of about 0.48, 0.50 and 0.61 and simulates to show that the proposed algorithm performance is significantly improved compared with the existing ALOHA-based algorithm. Originality/value The proposed RFID anti-collision algorithm is beneficial to improve the moving speed and identification reliability of the RFID robots in complex environments.

Fog radio access networks has emerged as a promising evolution path for 5G network architecture to satisfy the explosively increasing demands of high-speed data services and massive access requirements of various devices. As a key complement to this path, proximity-based device-to-device (D2D) communications with high transmission rate can better support the above services. For resource allocation in D2D communications, there are two fundamental challenges that should be addressed: 1) how to utilize the mobile characteristics and social relationships among users to enhance the user throughput and 2) how to efficiently allocate the limited resources to guarantee each user's service satisfaction. In this paper, a D2D dual-link enhanced communication model is developed to improve the throughput of D2D and cellular users (CUs) simultaneously. Then, based on the mobility characteristics and social relationships among users, an optimization problem about resource allocation is formulated and solved with the objective to maximize the user satisfaction. The simulation results verify that our proposed scheme can improve user satisfaction and throughput under limited spectrum resources simultaneously.