大空间双模多频段射频识别复合定位

摘要

For RFID indoor positioning of a large area,we proposed a method of hybrid location using dual-mode and multi-band RFID. The object to be located simultaneously takes an active tag and a passive tag. To avoid inter⁃ference among the UHF band reader antennas,when the microwave band reader communicates with the active tag activated by low frequency band signal,UHF band reader antennas regionally work according to the signal of the ac⁃tive tag;to improve the Bayesian probability location algorithm,the number of packets received by UHF band read⁃er antennas from the passive tag during a fixed time is used to locate the object,while regionally screening maxi⁃mum posterior probability position and taking advantage of the Euclidean distance to correct location coordinates in the position calculation process. Results of experiment show that the method we proposed can not only reduce inter⁃ference among reader antennas obviously but also decrease the positioning tolerance by 59.86% compared with LANDMARC algorithm.%针对室内大范围射频识别定位，提出一种双模多频段射频识别复合定位方法。被定位对象同时携带有源和无源两种模式的标签，微波频段阅读器与被低频频段信号激活的有源标签通信，根据有源标签信号区域选通超高频频段读写器天线，以减轻读写器天线之间干扰；以固定时间读写器天线对无源标签的收包次数为定位参数，在被定位对象位置计算过程中分区筛选最大后验概率位置并利用欧式距离修正定位坐标，完成贝叶斯概率定位算法的改进。实验验证表明，本文提出的复合定位方法，不但可以改善大空间定位中读写器天线间的干扰，而且与LANDMARC算法相比较，定位误差降低59.86%。