Research Of Networking Technologies Under Cognitive Radio Ad-hoc Networks

The shortage of spectrum resources limits the development of wireless communication and traditional ad hoc networks.With the help of cognitive radio technology and the allocation as well as utilization of spectrum dynamically,the problem of spectrum scarcity can be effectively alleviated Thus the new research field of cognitive radio ad hoc networks is greatly developed.This paper is devoted to the research on the theory of the initial stage of cognitive radio ad hoc networks.First of all,it is focus on the analysis of rendezvous for various users in the networks.A mathematical model is constructed to discuss the probability of rendezvous under different situations.Based on the result,a new Channel-Grouping based algorithm is proposed for decentralized rendezvous.The basic idea behind the algorithm is to divide all channels into small sets,reducing the number of selectable channels in each round and thus improving the probability of successful rendezvous.Then,the algorithm is modified and enhanced for the situation of multiple users.Numerical results show the excellent performance of the proposed scheme.In the end,on the basis of topology discovery technology in traditional ad hoc network,a new cluster-based Hybrid Topology Discovery protocol is presented.The performance of the protocol is analyzed in detail from many aspects.