基于BDS和RFID的现代有轨电车定位信号完整性研究

Study on Positioning Signal Integrity of Modern Tram Based on BDS and RFID

现代有轨电车作为一种城市交通工具,其行驶中卫星信号会受到折射、反射、多路径效应等因素的影响,造成卫星定位精度差、信号失锁等问题。为此本文提出一种基于BDS和RFID的提高定位信号完整性的方法。将北斗卫星UTC引入RFID的TOA算法中,得出基于RFID的定位方程,同时在北斗卫星最佳位置的判决门限中引入水平精度因子HDOP,得出伪距测量方程,最后通过结合最小二乘法与小波滤波得出位置坐标。经测试该方法有效降低了卫星信号的多路径效应,弥补了单一北斗卫星定位的不足,定位精度提高了50%。最后分析有效数据传输及误码率,证明该方法能满足车-地通信的要求,定位信号的完整性提高了71.2%。

Modern trams,as a tool for urban transport,are affected by their satellite signal refraction,reflection,multipath effects during operation,resulting in satellite positioning accuracyand signal lock loss problems.This paper presented a method based on BDS and RFID that improves the positioning signal integrity.The Beidou satellite UTC was introduced into the RFID-TOA algorithm to obtain the RFID-based positioning equation,while the HDOP level pseudorange measurements were introduced into the decision threshold of the best position of Beidou satellite.The position coordinates were obtained by combining the least square method and wavelet filtering.The test results showed that the proposed method can effectively reduce the effects of multipath satellite signals to make up for the shortage of single Beidou satellite positioning,while improving positioning accuracy by 50%.Finally,the analysis of the effective data transmission and bit error rate proved that the method can meet the requirements of the TWC with the increase of the integrity of the positioning signals by 71.2%.