Research On Clustering And Channel Hopping Sequence Design Algorithm In Cognitive Wireless Networks

With the rapid development of wireless communication technologies,people's demand for wireless spectrum is also growing at a high speed.The ever-increasing contradiction between the demand for wireless spectrum and the low utilization of spectrum resources is increasing.The proposed cognitive radio technology provides powerful technical support for solving this contradiction.In order to expand the scale of the network,related technologies for multi-hop cognitive wireless networks are also becoming hot topics.Under the distributed multi-hop cognitive radio scenario,how to effectively manage a large-scale network topology and design an effective channel rendezvous policy are two technical problems in this scenario.In order to expand the network scale and simplify the topology management of the network,this paper first studies the clustering algorithms in multi-hop cognitive wireless networks,and analyzes the shortcomings of existing clustering algorithms.Based on the relevant literature,we added our own improvement ideas,combined the user's historical statistical information of the channel state with the bipartite graph,and proposed a bipartite graph clustering algorithm based on the channel idle probability list.Through experimental simulation,we prove that the proposed algorithm improves the performance of existing algorithms in terms of cluster head load balancing and the average number of available channels of user links in each cluster.Next,in order to achieve the rendezvous that cognitive users can receive and send data on multiple channels successfully,this paper focuses on the channel rendezvous strategy based on channel hopping sequence,and analyzes the common shortcomings in the classical frequency hopping sequence design algorithm.Combined with the needs of cognitive users,and the Latin square matrix and the linear congruential random number generator were introduced into the sequence design algorithm.We propose our own frequency hopping sequence design algorithm by increasing the flexibility of sequence design.Through the combination of theoretical derivation and experimental simulation,we prove that our algorithm can improve the rendezvous delay and channel utilization's fairness of the existing algorithms.