Research On Routing Algorithm In Cognitive Mobile Ad Hoc Networks

Recently, the increasing developing wireless communication technology and wireless services lead to wide spread of powerful mobile devices and M2M (Machine to Machine)communications. Especially, the wide application of smart phones causes the rapid increasing of users and communication traffic. Hence, the limited licensed spectrum can not meet the requirement of wireless spectrum resouces for communication and has become one of the bottlenecks for 5G, Internet of things and Internet of vehicles. According to the literature, it is found that the utilization rate of different bands is between 15% and 85%, and the utilization rate of each band is dynamic and maybe underused in some special location and time. There is a large number of white areas in the authorized band, even in very crowded frequency bands, such as mobile cellular communication bands, there are idle phenomena in individual periods.Hence, in order to ensure the healthy and sustainable development of the wireless communication industry, we need make full use of spectrum resources.Cognitive Radio (CR) is a promising wireless communication technology which can make the spectrum fully utilized. CR can sense idle spectrum and use them without interfering licensed user and it can improve the spectrum resouce utilization.Routing technology is one of the most important core technologies of cognitive radio network (CRN). However, environmental complexity of CRN makes the routing protocol of CRN face many new challenges. Hence, based on the environmental characteristics of CRN and the traditional mature routing protocol, this paper designs a superior routing protocol.Firstly, we introduce the research background, the progress and application trends, as well as the purpose and contributions of the thesis. Then the routing protocol of existing CRN traditional Ad Hoc network is analyzed. In addition, we simulate and analyze several typical routing metrics, then determine the research direction of the thesis.Secondly, according to the environmental characteristics of CRN, considering the dynamics of spectrum in cognitive mobile Ad Hoc network, the mobility of nodes, the node load and the end-to-end delay, a routing protocol based on service priority is proposed, the algorithm can adjust the route metric factors according to the type of data transmission to meet their requirements. In the routing maintenance phase, by predicting the moving speed of mobile node and link-state, the routing recovery is triggered before the link outage, to avoid loss of data packets.Finally, through various simulations of CRCN platform in NS2, the proposed routing algorithm shows the improved performance of delay, throughput, packet delivery ratio.