Abstract: Localization is one of the key technologies in wireless sensor network.Only the coordinates estimated by three anchors are used in trilateration localization algorithm，but the value estimated can not reflect the unknown node’s actual coordinates.A algorithm is proposed to choose the proper distance information.A distributed algorithm is also proposed to reduce the localization error and improve the robustness.This algorithm utilizes angular weighted function to integrate muti-coordinates into the finally coordinate.

摘要： 定位技术是无线传感器网络的关键技术之一，传统三边测量定位算法利用三个锚节点一次确定未知节点的位置坐标，而单次估算的坐标值无法准确反映未知节点的实际位置。提出了一种以RSSI值和通信质量为权值的锚节点选择算法，筛选对未知节点影响力大的锚节点用于节点定位计算。在此基础上，使用角度权重函数综合多次估算的未知节点坐标信息，进而确定未知节点位置坐标。仿真结果表明，与原三边测量定位算法相比，改进算法对锚节点随机分布有较高的鲁棒性，定位精度有较大提高。