Abstract: In wireless sensor networks，the sink inject a message into network，with the message flooding，a tree topology established.The traditional backoff mechanism and routing strategies easy cause fierce collision，the route easy to paralyze and non-optimized routing tree.In this paper，a wireless sensor network optimization routing tree algorithm is proposed.This algorithm defines route valid term，the father node priority queue，and proposes the overlapping backoff window strategy.Simulation result shows this algorithm can construct the route tree effectively.

Key words: Wireless Sensor Networks（WSN）, routing tree, overlapping backoff window

摘要： 针对无线传感器网络使用洪泛建立路由树时，传统的碰撞退避机制和路由树构造策略容易造成消息剧烈碰撞、路由容易瘫痪和建立非优化路由树等问题，提出了无线传感器网络优化路由树构造算法。算法定义路由有效期、父节点优先级队列，并结合跨层设计思想，修改MAC退避算法，提出交叉退避窗口策略，并经仿真实验证明能够有效地构造出较优的路由树。

关键词: 无线传感器网络, 路由树, 交叉退避窗口