严重遮挡非视距环境下的三维定位方法

在严重遮挡非视距环境中，由于定位源与未知节点之间被障碍物遮挡而无法检测直射路径，极大地制约了无线定位方法的应用。提出一种能够规避直射路径遮挡现象的三维定位框架，利用单次反射路径和方位信息，论证了定位源、未知节点和散射体的三维空间位置关系，提出了基于最小二乘准则的空间位置优化算法，并推导出空间位置的求解方法。同时对定位算法进行均方根误差（RMSE, root mean-square error）的理论分析。通过蒙特卡罗仿真实验分析了三维定位框架中距离和方位偏差对算法性能的影响，仿真结果与算法的RMSE理论结果相符，说明了三维非视距定位算法的有效性。

Three-dimensional localization under severely obstructed NLOS environment

In the severely obstructed NLOS(non-line-of-sight) environment, obstacles between the UN (unknown node) and RS (reference station) made the DP (direct path) undetectable. It greatly restricted the application of wireless localization method. A three-dimensional localization scheme, which utilized the distance and orientation information of single-bounce signal, was proposed to evade the DP blocking effect in three-dimensional NLOS environment. Within the proposed localization scheme, three-dimensional spatial location relationship among the RS, UN and scatterers was proven. An optimization algorithm based on least mean square was proposed and the mathematical solution to the position relationship was derived. Furthermore, the performance of algorithm is studied by using RMSE (root mean-square error) analysis. Through Monte-Carlo simulations, how distance and orientation deviation of three-dimensional localization frame affect performance of algorithms is examined. It is also demonstrated that the analytical results closely match the simulations, which verifies the effectiveness of the proposed three-dimensional NLOS localization algorithm.