An Efficient RFID Tag Search Protocol Based on Historical Information Reasoning for Intelligent Farm Management

Abstract

Due to the ability to simultaneously interrogate multiple tags with a far operating distance, radio frequency identification (RFID) has been widely used in modern farms to improve management efficiency. In smart farm applications, how to quickly locate and search some specified items (e.g., animals) is a critical problem, for which tag searching can be used to solve the problem. While there are some works on tag searching, they are designed for static objects and cannot meet the time efficiency requirements where the searched animals’ movement brings challenges. In this paper, we propose SHIR, an efficient tag-searching protocol based on historical information reasoning, which can be applied in scenarios containing mobile tags that cannot be well handles in existing tag search protocols. By continuously counting the difference between the predicted reply signal and the actual signal received from tags for multiple rounds, SHIR avoids the waste of time slots and achieves high time efficiency. Furthermore, it can infer unverified tag status through historical information to speed up the search process. We further propose the Enhanced SHIR (ESHIR) protocol by filtering out the interference tags in the query area to avoid wasting time verifying interference tags. Compared with previous probabilistic approaches, SHIR gets accurate search results with no false positives. Extensive experimental results show that our best protocol can improve the time efficiency by up to 42% compared with the the-state-of-art solution.