一种新的拓扑无关的按需分配多信道自组网MAC协议

A Novel Topology-independent MAC Protocol with on-Demand Channel Assignment for Multi-Channel Ad-hoc Networks

本文针对节点具有多个可用信通的自组网,提出了一种与拓扑无关的多信道MAC接入协议,协议采用按需预约的方式进行动态的信道分配,通过携带在信道预约消息中的节点邻居状态信息实现节点信道状态的更新。该协议所需信道数与网络的拓扑和度无关,克服了拓朴相关的多信道MAC协议不适用于节点密集的应用场合的问题。在协议开销增加很小的情况下,每个节点只需要一部半双工收发信机就能够实现在多个信道上高效的数据收发,不需要节点间的时钟同步,极大地降低了对网络节点设备的硬件要求,具有良好的应用前景。仿真结果表明,协议在网络总吞吐量、端到端时延等方面具有优良的性能。

A novel topology-independent medium access control scheme for ad hoc networks with multiple channels available is presented in this paper, which follows an 'on-demand' method to assign channels to mobile hosts dynaml- cally, and exploits the status information of neighbor nodes piggyback on channel-reservation messages to update the channel status recorded in nodes. The number of channels that the protocol requires is independent of the network topology and degree makes the protocol well adaptive to crowed environment, for which the topology-dependent MAC protocols are inappropriate. The protocol may lead to efficient data transmission on multiple channels with only one half-duplex transceiver each node, at the same time with few control messages exchange as well as little overhead in- crement, and without clock synchroniztion, which greatly simplifies the hardware configuration of nodes within net- work and broads its usage areas. By presenting and analyzing simulation results, the protocol is shown to result in good performance in the aspects of packet delivery ratio and average end-to-end delay, which makes it well adaptive to the dynamic ad hoc network environment.