On The Multi-Channel MAC Protocols Of Wireless Mesh Networks

Wireless Mesh Network (WMN), a static multi-hop wireless network connecting routers and terminal devices with wireless links, is a new type of broadband wireless access systems. A WMN is a combination of WLANs and mobile Ad hoc networks with the characteristics of reliability, self-organization and self-healing. Nowadays, researches on WMNs have been very popular around the world. Since channel allocation and management is a key factor influencing networks performance optimization, MAC protocols for WMNs are gaining significant attention.Based on the analysis of conceptions, architectures, key technologies and the existing MAC protocols of WMNs, this thesis focuses on multi-channel MAC protocols of WMNs. Firstly, a single-channel MAC protocol 802.11 DCF is introduced, then MMAC and SSCH in single-transceiver multi-channel MAC protocols, as well as MUP, DCA and PCAM in multi-radio MAC protocols are described. After comparing the performances of each protocol, summarizing their merits and drawbacks, this thesis analyzes a multi-transceiver multi-channel MAC scheme named as Dual Transceiver based MAC (DTM) in detail. In DTM scheme, each node has multiple channels with two wireless transceivers. The simulation results of DTM are compared with DCF and SSCH, showing that DTM has the largest aggregated throughput and the smallest end-to-end delay in forward and local traffic in single-hop scenes, as well as local traffic in multi-hop scenes, then SSCH and DCF in sequence.