Abstract: The wireless environment is supposed to the LOS in the classic wireless location algorithm.Although the reflection，refraction etc. do exist in the real environment，so the tolerance of the location must be more if we use the classic algorithm.Here we put forward one algorithm to mitigate the fact of NLOS.The algorithm uses the emendation factor and iterate gradually so as to mitigate the fact of NLOS.Simulation shows that the algorithm improves the accuracy of location better than the general algorithm，and the complication is low.

Key words: emendation factor, iterative algorithm, ML, NLOS, TDOA

摘要： 经典的定位算法都是基于无线环境为视距环境（LOS），但在实际信道环境中，由于存在反射、折射等从而导致传播环境为非视距的情况，因此经典定位算法应用于实际信道环境中必然会导致较大的定位误差。提出一种消除非视距影响的TDOA算法，本算法采用校正因子的方法，通过逐步的迭代，从而消除非视距的影响，仿真表明，在非视距环境下，该算法的确比常规算法能够提高定位精度，且运算量较小。

关键词: 校正因子, 迭代算法, 最大似然方法, 非视距, 到达时间差