提出了一种基于图着色法的无线传感器网络分布式链路调度(DLS)协议以减小调度周期长度、降低网络能耗。采用的策略是先对任意节点构建两跳邻居范围内的冲突图, 然后根据每条链路在干扰图中的优先级及干扰度决定时隙分配的先后顺序, 从而解决传统随机调度方法调度周期较长及节点状态转换频繁的问题。由于该调度策略尽可能地为节点分配相邻时隙, 减少了节点不必要的状态转换, 从而降低了网络能耗。对基于干扰度和优先级的联合调度策略表现出的减小调度周期长度、降低网络能耗的特点进行了分析。网络仿真结果表明, DLS协议比DS-fPrIM(Distributed Scheduling-fixed Power Protocol Interference Model)及DRAND(Distributed RANDomized time slot sceduling)协议的调度周期长度少1~2个时隙, 其能耗与DS-fPrIM协议的调度能耗相当, 但二者都比DRAND协议的调度能耗低。另外DLS协议比DS-fPrIM及DRAND协议平均每周期少1次状态转换, 说明提出的分布式链路调度协议能效较高。

To decrease the scheduling length and energy cost of a wireless sensor network, a Distributed Link Scheduling (DLS) protocol was proposed based on graph coloring. With proposed scheme mentioned in the protocol, every node was required to construct its two-hop conflict graph, and the scheduling order of every link was decided by its priority and interference degree in the conflict graph. The proposed DLS algorithm relaxes the problem of longer scheduling caused by randomly scheduling and frequent state transition in traditional algorithms. Since the DLS can assign the adjacent slot for every node, the times of node's state transition and the energy cost can be decreased. The efficiency on decreasing the scheduling length and network energy cost of DLS was analyzed. The simulation results show that the scheduling length of the proposed DLS protocol is less about 1-2 slots than those of the Distributed Scheduling-fixed Power Protocol Interference Model (DS-fPrIM) and Distributed RANDomized time slot scheduling (DRAND ) and its scheduling energy cost is the same as that of the DS-fPrIM, but less than that of the DRAND. Moreover, the state transition of the DLS is once less than those of the DS-fPrIM and DRAND. The results also indicate that the proposed DLS protocol has good performance on energy efficiency.