Reserch And Implementation Of Interference-aware Based Routing Algorithm For Wireless MESH Networks

As a high capacity,high speed distributed network,wireless mesh network is self-organized,infrastructure free,highly scalable and highly recoverable and is considered the next generation wireless communication network by industry,which provides better service.Routing protocol,which is critical to inter-connectivity and data exchange among network nodes,has important significance for performance optimization of wireless mesh network.The main task of WMN routing protocol is to establish and maintain multi-hop routes,which is the essential of the reliable data forwarding.Routing metric,which uses reasonable mathematical model to describe network quality,is the key factor of path selection.Therefore,routing metric has great impact on routing protocol.Due to the nature of wireless network,it is vulnerable to environment noise,channel interference,signal loss etc,taking account these factors can greatly increase the network quality of service when designing routing metric.Focusing on the interference issue in wireless mesh network,this study presents a routing algorithm improvement on HWMP routing protocol,which optimizes the network quality of service.The following work is carried out:Firstly,IA-HWMP aims at selecting routes with minimum interference,maximum throughput and minimum packet loss.The scope of interference in WMN is studied and confirmed,and the interference calculation is modeled to measure the interference accurately.Based on the new SINR mathematical model,a new interference aware airtime link metric called IA-ALM is proposed.The HWMP routing protocol is optimized by designing the control message NREQ and NREQP to acquire the information of interference nodes,which proposes an interference aware routing protocol IA-HWMP.Secondly,aiming at a long-distance wireless mesh network device,WM-R531,which is widely used in maritime rescue,tunnel operation,disaster rescue,urban support,the specifications of device,the design principle of hardware,and the architecture of wireless driver in software system is introduced.With the WM-R351 device,IA-HWMP routing protocol is implemented,the definition of key data structure,the assembling,sending and receiving of message NREQ/NREP,and the algorithm implementation of new interference ratio IR~*are described in detail.The time complexity of adding,deleting,searching and modifying neighbour nodes are analyzed.Finally,the comparative test on throughput,latency and stability of WM-R531 device with IA-HWMP and HWMP is performed in Shanghai Dishui Lake,Chaohu Lake in Anhui,Nanjing He Yan Road river-crossing Tunnel,Nanjing Zhengfang Middle Road,Nanjing Jiangning Wireless Valley,in which Batman-adv routing protocol is added.The results shows that the throughput of IA-HWMP is about 5.65%higher than HWMP and the latency of IA-HWMP is about 8.67%lower than HWMP at maximum.When IA-HWMP is compared with Batman-adv,the advatage is 5.16%and 7.85%.