基于自适应调制与编码的多跳CDMA Ad hoc网络跨层性能分析与建模

Cross-layer Analysis and Modeling for Multihop CDMA Ad hoc Networks with Adaptive Modulation and Coding

给出了一种新颖的多跳CDMA Ad hoc网络跨层性能分析模型。首先建立了随机网络拓扑的数学模型,进而分析了采用MFR路由策略时源节点到目的节点所需跳数的概率分布情况。然后结合自适应调制编码方案,分析了节点中发送分组队列的平均队列长度、丢包率及平均排队时延等分组级QoS性能。在此基础上,分析了网络的端到端时延和吞吐量性能,并讨论了节点传输范围、发送分组队列长度、扩频增益对网络性能的影响。所提出的分析模型虽然考虑的是特殊的MAC协议和路由策略,然而这种方法可以用来分析采用其它MAC协议和路由协议的系统。

A novel cross-layer analytical model for multihop CDMA Ad hoe networks was proposed,which considers the effect of the physical layer, the MAC lay and the route layer on the performance of the networks. Firstly, the probability distribution was derived for the link distance between two randomly positioned nodes, and the probability distribution of the number of hop between the source node and the destination node based on MFR route strategy was also considered. Then, combining with adaptive modulation and coding, packet-level QoS performance of the network was analyzed. Moreover, the end-to-end delay and throughput with retransmission mechanism were analyzed, and the effect of transmission range, the queue length and spread gain on the network performance was discussed. The proposed model considers the special MAC protocol and route strategy protocols; however, the approach can be extended to other MAC protocol and route strategy as well.