Abstract: The three beacons node-coordinates of linear relationship make trilateration fail in locating with the decentralized architecture for Cricket wireless sensor networks，which causes location system to be in redundant calculations even collapsed state.Twice-iteration and mini-distance-decision are proposed to maintain system to run healthily under the trilateration-failure condition.The improved scheme proves to make the system obtain high stability and efficiency.

摘要： 在无中心构架的Cricket无线传感器网络室内定位系统中，呈线性关系的参与定位的3个参考节点坐标会使三边测量法失效，从而导致系统进行大量的冗余计算甚至崩溃。采用参考节点坐标的最小距离决策和二次迭代法，使得系统在三边测量法失效的前提下仍能正常运行。通过实验证明这种改进方案提高了系统的稳定性和效率。