用于多跳无线传感器网络的自适应退让算法

为了解决802.15.4标准MAC层规定的CSMA-CA接入方式的退让算法不能很好地满足动态网络和多跳要求问题,提出了中继数据优先的策略,该策略能更可靠地传递远端节点的信息,以适应突发流量和非突发流量网络.另外还提出了一种新的自适应流量变化且避免第2次冲突的退让算法(AASC),离散M arkov链模型的数值分析和仿真证明新算法在网络节点数目变化时有更高的吞吐量,适应突发量和非突发流量应用,在多跳通信方式下能更多地中继远端节点的数据到目的节点,并同时减少节点的重传次数节省能量.

Adaptive backoff algorithm for multihop wireless sensor networks

Since CSMA-CA's backoff algorithm specification in the IEEE 802.15.4 standard can not adapt to dynamic network and multihop communication,a strategy under which relay data have higher priority is also proposed.This strategy guarantees that remote node's packets are transmitted reliably to destination node,whether network is burst flow or non-burst flow.A new backoff algorithm that can adapt to flow and avoid secondcollision is also proposed and analyzed in this paper.The paper models the networking using the theory of discrete time Markov chains.Numerical results and OPNET simulation show that the new algorithm can adapt to burst flow better and produces throughput improvements,whether the number of node is large or small.Simulation results also show that the new algorithm relays more remote node's packets to destination node and saves energy through reducing retransmission in multihop networks.