中文摘要：

为了降低大型无线传感器网络的时间同步能耗，分析并计算了同步信息发送和接收过程中的时延组成，得出节点的时钟偏差，并利用线性回归法计算节点的频率漂移，在此基础上，将异构网络中的中继节点作为簇首，首先实现簇首与sink节点的时间同步，然后实现簇内的时间同步。分析表明，本算法同步误差只与传播时延和编解码时延有关，同时在同步过程中所需发送和接收的同步字节少，可以延长网络的生命周期。

英文摘要：

In order to low energy consumption of time synchronization in large wireless sensor networks （WSN）, the components of transmission delay of synchronization message between sender and receiver are analyzed and computed, the time offset of nodes are obtained, and the frequency drift are computed by linear regression method. On this basis, the relay nodes in the heterogeneous WSN are taken as cluster heads, the time synchronization between cluster heads and sink node are firstly realized, and then the time synchronization in clusters are realized. Analysis indicates that, for one thing, the error of this algorithm is only relative to propagation delay, coding and encoding delay, for another thing, synchronization words needed in the process of synchronization are less, so this algorithm can prolong the lifecycle of WSN. 3 figs, 7 refs.