基于NLOS下混合滤波加权组合定位算法的仿真

Radio Communications Technology

超宽带(Ultra Wide Band, UWB)技术是一种新兴的无线载波通信技术,其具有发射信号功率谱密度低、系统复杂度低、定位精度高等优势,尤其适用于像电厂等密集多径场所的高速无线连接,但在传输过程中信号会被环境中的各种因素影响,进而会影响室内定位的精度。基于此,针对室内非视距(Non Line of Sight, NLOS)环境下,提出一种非视距混合滤波加权算法,能够有效对测距数据进行平滑处理,进而降低异常值的影响,再利用时间差定位法(Time Difference of Arrival,TDOA)测量方法,在原始Chan算法的基础上提出一种改进的Chan定位算法,解决NLOS误差引起的定位信息不准确的问题,最终实现更精准的TDOA定位。仿真实验证明,所提算法在室内NLOS环境中具有更高的定位精度。

Ultra Wide Band(UWB)technology is a new wireless carrier communication technology.It has advantages of low power spectral density of transmitted signal,insensitive to channel fading,low system complexity and high positioning accuracy.It is especially suitable for high-speed wireless connection in indoor places such as power plants.However,during the transmission process,signal will be blocked and reflected by obstacles such as walls,equipment and people movement in the environment,which will affect the accuracy of indoor positioning.Therefore,in indoor Non Line of Sight(NLOS)environment,a hybrid filter weighting algorithm is proposed to enable it to effectively smooth ranging data and reduce the impact of outliers.Then,a Time Difference of Arrival(TDOA)measurement method is used to substitute the ranging data into the optimized Chan algorithm,and an improved Chan positioning algorithm is proposed to solve the problem of inaccurate positioning information caused by NLOS error,and finally achieve more accurate TDOA positioning.Experiments show that the positioning accuracy of this algorithm is improved in indoor NLOS environment.