基于时分频分的无线传感器分簇网络MAC层协议

针对无线传感器网络节点能量有限的特点，提出了一种应用于簇结构的媒质接入控制（MAC）协议．即FT-MAC协议．该协议在簇内使用分时通信，利用粒子群算法优化时隙分配，减小状态转换的能量消耗，为了消除网络通信中的簇间干扰，FT-MAC使用启发式搜索算法为相邻簇分配不同的频率，在仅需保持簇内时间同步的条件下，FT-MAC通过网关节点的特殊工作模式实现了簇间通信，避免了全网时间同步所造成的大量能耗．仿真结果表明，与其他媒质接入控制协议相比，FT-MAC具有能耗小、网络数据包延迟时间短的优点．能满足大规模无线传感器网络应用的需要．

Medium Access Control Protocol for Wireless Sensor Cluster Network Based on Techniques of Time Division and Frequency Division

To solve the problem of limited energy of sensor nodes, a medium access control （MAC） protocol, i.e. FT- MAC protocol for cluster-based wireless sensor network （WSN）was proposed. In FT-MAC, the protocol based on time division multiple address technique was employed in cluster, and timeslot allocation was optimized by particle swarm optimization （PSO） for reducing the energy consumption in state transition. In order to eliminate inter-cluster interference, different frequencies were allocated to neighboring clusters with a heuristic search algorithm. In addition, communication between clusters was attained through gateways with time synchronization only in each cluster, which reduced the burdens of time synchronization in entire network. Simulation results show that FF-MAC is an energy-efficient protocol with small delay time per packet, which can meet the requirements of large-scale WSN.