关键词: UWB TW-TOA, 标准时间偏差, NLOS误差, 偏移卡尔曼滤波

Abstract: In allusion to the UWB TW-TOA distance measurement is affected by the standard time deviation and the NLOS error obviously,this paper adopted fourth order poly nomial fitting model to demarcate the standard time deviation,designed a new method to identify NLOS error and restrained it based on the migration of Kalman filtering.This method combined the distance measuring residual with Kalman filtering, to distinguish the NLOS error,and put the residual into the iterative Kalman filter,modified Kalman filter outliers,got the measured value which is eliminated by NLOS error.By using the measured experiments to validate the above algorithm,results show that after a standard time calibration and NLOS error identification and suppression,the distance measurement precision of the UWB TW-TOA can reach millimeter level in the LOS conditions,and in the NLOS surroundings,the distance measurement can reach 0.2 m compared to the 0.5 m before.All these prove that the method of this paper is correct and feasible.

Key words: UWB TW-TOA, standard time deviation, NLOS error, offset Kalman filter