面向移动自组网的分布式认知MAC协议改进设计

Design of distributed cognitive radio MAC protocol for MANET

针对移动自组网MAC协议未考虑节点移动性、缺乏功率控制机制、算法开销较大等问题,改进设计基于信道可维持时间的分布式认知MAC协议。新协议建立了节点存储信息结构,根据节点功率与移动速度的关系,构建信道可维持时间模型,并改进信道感知和数据传输算法,增加移动性和信道增益考虑,降低速度和功率对信道感知的影响,提高协议对移动性的适应能力。结果表明,对于中低速网络而言,该协议在不增加控制开销的基础上,丢包率、时延和频谱利用率等性能得到较大改善。

This paper proposed a new distributed cognitive radio media access control （MAC） protocol aiming at solving the problem of nodes mobility, power control mechanism and algorithm complexity in mobile Ad hoc network （MANET）. The new protocol constructed data storage structure at first. Then it defined channel maintenance time model according to the relation- ship between power and velocity of node. At last it both took nodes mobility and channel gain into account in process of chan- nel sensing and data transmission to reduce impact of channel sensing from velocity or power and raise the adaption of mobile environment. Results show that, network performance of proposed protocol, such as packet drop rate, delay and spectrum uti- lization are enhanced greatly, not increasing control overhead.