A Study Of Cooperative Multicast Relaying Scheme And Perfomance Analysis In Wireless Mesh Networks

Wireless mesh network (WMN) has emerged as efficient means to expand thewireless reach of metro broadband deployments at a variety of locations or scenarios. Itprovides high quality service to end users as the last-mile of the Internet. Multicastprovides an efficient mechanism for distributing data among a group of nodes, such asonline games and video conferences. With the increasing popularity of contentdistribution and multimedia applications, efficient multicast communication becomesessential for the wide deployment of WMN. Especially in recent years, with thetechnology development of cooperative communication, the efficiency of wirelessmulticast network transmission has been further improved.Through radio characteristics of wireless channel with multi-user for multicast gainand multi-user diversity gain, cooperative communication is considered to be effectiveto conquer channel fading. This dissertation gives an in-depth research for cooperativecommunication in WMN network multicast transmission context. The maincontributions are described as follows:(1) The performance of AF and DF algorithm in Rayleigh channel is analyzed, andthe SER expression is derived and validated by simulation.(2) An energy efficient multicast relay selection algorithm for Two-phasecooperative multicast scheme is analyzed and researched. In Two-phase cooperativemulticast scheme, the multicast process is divided into two stages. The successfullyreceived users of the first phase will be multicast relays for the second stage. Althoughthe throughput performance of the system significantly increased, the shortage is that,without considering relay-selection problem, traditional Two-phase cooperativemulticast costs power consumption too much. This paper puts forward an energyefficient optimal relay selection algorithm for Two-phase cooperative multicast scheme.The siumulation results show that, the total power cost can be greatly reduced withoutsacrificing the multicast system throughput after introducing this relay strategy.(3) A distributed relay selection algorithm for cooperative multicast in WMN isanalyzed and researched so as to meet the demand for the coverage of multicast service. From the perspective of WMN multicast service coverage. Aimed at the centralizedalgorithm failed to provide better support for mobile users, a distributed cooperativerelay selection algorithm is analyzed. The simulation results show that, in the mobilesituation, no matter in terms of the reliability of transmission or resource cost, thedistributed relay selection algorithm is superior to the centralized algorithm.In summary, to address the issue of power consumption and coverage demands inWMN cooperative multicast, several relay selection algorithms are researched based onthe performance of the cooperative multicast strategy. This dissertation’s research haspractical significance for the future WMN multicast technology’s development.