Research On An Error Suppression TDOA Algorithm Based On UWB Positioning

In today's information society,people's work and activity scenes gradually shift from outdoor to indoor.With the rapid development and commercial deployment of 5G technology and the continuous upgrade and application of Internet of Things technology,people are increasingly demanding real-time and accurate indoor location information.Traditional indoor positioning technologies are mainly infrared positioning,ultrasonic positioning,Wi-Fi positioning,ZigBee,Bluetooth,etc.,but these positioning technologies are greatly affected by signal strength and time errors,and the positioning accuracy or positioning distance indoors is not as good as UWB positioning.UWB technology is widely used in the research of indoor positioning technology because of its advantages such as low system complexity,low power spectral density of signals,strong multipath resolution,and strong penetrability.This paper mainly studies the basic principle,channel model and positioning method of UWB indoor positioning technology.Firstly,by simulating the channel of IEEE802.15.4a,the reason for selecting the CM2 channel as the channel environment in the complex indoor environment of this paper is analyzed;Secondly,by comparing four UWB positioning methods,it is concluded that the positioning performance of the TDOA positioning method is better,and the main errors and error causes that affect the positioning accuracy of the TDOA algorithm are analyzed in depth;Finally,aiming at the non-line-of-sight errors and multipath interference that may cause errors in positioning accuracy,a variety of classic TDOA algorithms are simulated and compared,and the effects of multipath interference and non-line-of-sight errors on TDOA ranging results are obtained based on the comparison results.Therefore,an improved multipath suppression algorithm and an improved GaussNewton iterative algorithm are proposed,and the two improved algorithms are merged to obtain the multipath suppression CGNC algorithm.The simulation results show that the merged algorithm can effectively suppress multipath interference and non-line-of-sight errors.In the end,this paper uses the Hainan EVK3.0 indoor positioning experimental platform independently developed by the laboratory team to test the proposed multipath suppression CGNC algorithm with the original Gaussian Newton iterative algorithm and CHANTAYLOR algorithm,and compare and analyze it with MATLAB simulation.It is found that the absolute positioning error measured by the multi-path suppression CGNC algorithm in a complex laboratory environment is 0.351 m;compared with the classic CHAN-TAYLOR algorithm,the multi-path suppression CGNC algorithm improves positioning accuracy by 80.7%;Based on the original CHAN-Gauss-Newton iterative algorithm,the positioning accuracy is improved by 95%.In summary,the positioning performance of the multipath suppression CGNC algorithm in a complex laboratory environment is greatly improved compared to the classic TDOA algorithm,and its positioning accuracy in a complex indoor environment is much higher than the original algorithm and the CHAN-TAYLOR algorithm.