Research On Anti-Collision Of UHF RFID System

Radio Frequency Identification (RFID) is a kind of non-contact automatic identification technology. With RF signal RFID system can automatically recognize targets and read relevant data. The system can work without human operation, in variety harsh environment. Radio frequency identification system can identify multiple objects in high-speed movement agile to run. But in UHF RFID systems, there are still a lot of problems to be solved, which have hindered the wide application of radio frequency identification system. This paper, based on an "863" specific project-"Research on RFID applications in communications test technology" (NO. 2006AA04A106), have in-depth research on some key technical issues of the RFID system function and practical application.Firstly, algorithms such as Aloha algorithm of random anti-collision algorithm and binary tree algorithm of deterministic anti-collision algorithm, which are now widely used such as anti-collision algorithm, are analyzed,, then throughput resulted from two algorithms are compared with conclusion. Based on the existing Deterministic Anti-collision Algorithms, Enhanced Dynamic Binary Search Algorithm is proposed. Compared with other algorithms which based on binary searches in the scenario of tag identification numbers are continuous, the algorithm greatly reduces the cycle times and can identify more labels in a short interval. Throughput can be close to 1, which show great advantages compared with other algorithm.Secondly, Reader Anti-collision problems are also studied. Focused on the frequency interference on the reader, the label-side reader interference is analyzed and simulated; it calculates the minimum distance to guarantee absence of co-frequency interference between two readers with a certain level of transmission power. It also described some of the anti-interference measures in the same frequency. For the label-side reader interference, a model for tag reader side collision is set up withsimulation and analysis. The identifiable probability of a single label would support communication process for future multi-label, multi-reader study environment.