Research On Channel Allocation And Routing Algorithms For Multi-radio Multi-channel Wireless Mesh Networks

Due to the progress of network technology and the emergence of new technologies,wireless mesh network has become a research hotspot in recent years again.This paper concentrates on channel assignment and routing algorithms in multi-radio multi-channel wireless mesh networks.The main work is as follows:Firstly,the paper studies the basic theory of wireless mesh network.Because WMN has a good application in the fusion of WiFi and bluetooth technology,the paper introduces the WiFi Mesh protocol and bluetooth Mesh protocol in detail.According to the characteristics and existing problems of MRMC WMN,the idea of improving network throughput is studied.We learn about three new channel assignment algorithms and study routing technology from the perspective of routing metrics by analyzing five classic routing metrics and two new routing metrics.Then,the paper summarizes the challenges of channel assignment and routing.Inspired by these algorithms,the channel assignment and routing algorithm suitable for MRMC WMN in this paper are proposed.Secondly,a static channel assignment algorithm MWLICA based on minimum weighted link interference is proposed.An integer linear programming(ILP)model is proposed to transform the channel assignment problem of MRMC WMN into an ILP model.Meanwhile,the concepts of node priority and link load weight are defined to classify the links and minimize the overall interference degree OCID of the links in the network.The paper uses the greedy heuristic algorithm to approximate the optimal channel assignment scheme so that the network throughput will be increased.Thirdly,from the perspective of routing,a load balance algorithm CR-HWMP is proposed to reduce the congestion in MRMC WMN.The algorithm uses the cache occupancy rate as an approximate calculation of the node congestion state,and divides the nodes into three congestion levels.The congestion information field is added to the PREQ management frame.At the same time,the algorithm introduces a penalty mechanism to impose different degrees of punishment on the nodes and design a congestion control routing metric to reduce congestion and enhance network performance.Finally,the above two algorithms are simulated on the NS-3 simulation platform,and different simulation scenarios are set.For the channel assignment algorithm,the throughput of MWLICA is about 7% higher than C-HYA and 32% higher than CCA on average under different available orthogonal channel numbers.Under different data streams,MWLICA is 10% higher than C-HYA and 40% higher than CCA.For the routing algorithm,two scenarios of different data transmission rates and different numbers of data streams are set,and the CR-HWMP,HWMP-P and HWMP-R algorithms are simulated.From the throughput point of view,CR-HWMP is at least 8% higher than HWMP-P and HWMP-R overall.CR-HWMP is at least 30% lower than HWMP-P and HWMP-R in terms of end-to-end average delay.The results show that MWLICA and CR-HWMP both effectively improve network performance.