脉冲超宽带系统中高精度的双门限TOA估计

针对非视距脉冲超宽带(IR-UWB)定位应用中,非相干TOA(Time of Arrival)估计算法精度的不足,提出了一种基于双门限和斜率(Double-Threshold and Slope,DTS)的首达信号时间估计算法。首达路径(Direct Path,DP)经过初始估计之后,根据能量采样序列最大值与最小值的斜率,拟合出最优归一化门限表达式;再联合UWB双指数信道模型的特点对双门限检测算法加以改进,实现TOA估计。在非视距环境下仿真、比较了DTS算法与几种IR-UWB常用TOA算法的平均绝对误差(MAE)。仿真结果表明该算法在不同UWB信道和信噪比环境下均获得了优异的误差性能。

High-accuracy double-threshold TOA estimation in impulse-radio ultra wideband systems

Aimming to improve the accuracy of ultra-wideband positioning under Non-Line-Of-Sigh(tNLOS)environment, a noncoherent TOA scheme is proposed by jointing double-threshold and slope estimations. By Direct Path(DP)search initially, the optimal normalized threshold fitting based on the slope of the maximum and minimum energy sample is obtained. Furthermore, double-threshold TOA estimation is adopted and improved by using the characteristics of double-exponent channel model. The Mean-Absolute Erro(rMAE)of the proposed algorithm is compared with other IR-UWB TOA estimations under NLOS environment. Simulations verify the outstanding performance of this scheme in different UWB channels and SNR environments.