A Novel Framework of Adaptive Routing Design in Cognitive Radio Military Networks*

摘要

With advanced wireless communication and networking technologies, cognitive radio ad hoc networks (CRAHNs) promise to revolutionize the next generation military networks. In this paper, we propose a framework of adaptive routing design in CRAHNs with time-varying availability of links. The proposed design framework includes a novel topology formation component and a routing scheme. The topology formation component forms a weighted directional graph model for the physical network and adapts it to time-varying changes of network links. Based on the graph model, the routing scheme computes optimal routing paths for a pair of nodes. An optimal routing path between a pair of nodes has the smallest hop count after minimizing the adjacent hop interference. The adaptive routing design also takes into account effects due to the number of pre-defined radio interfaces in each node as well as overall network traffic load. Concrete examples are given to demonstrate the adaptiveness and performance of the proposed routing design. Computational complexity analysis and preliminary simulation results show that the proposed routing design is more computationally efficient than an existing routing algorithm in cognitive radio networks. More importantly, the proposed routing design only requires incremental updates on the directional graph model without regenerating the entire graph to accommodate the time-varying changes of the avail-ability of links. This incremental updating procedure provides an efficient routing design and implementation solution for cognitive radio networks with link availability varying over time.