Multi-channel Multi-radio technology constitutes a viable approach to expand the capacity of Wireless Mesh Networks(WMNs). While many routing and channel assignment schemes have been proposed for WMNs, it is also important to integrate physical layer considerations into the routing process. In particular, multi-path fading is a challenging physical phenomenon, and it has been shown to be an important reason for packet loss in WMNs. In a multi-channel environment, the problem becomes more involved because different channels may undergo fading to varying extents. In addition there exists significant interference owing to the power leakage between the channels used by adjacent Mesh Routers (MRs). In this paper, we propose a Cross-layer CHannel Adaptive Routing protocol (XCHARM) for Multi-Radio Multi-Channel WMNs. XCHARM integrates routing and channel assignment during route setup, so that the interference caused by nodes transmitting on non-orthogonal channels in the same carrier sensing domain is greatly mitigated. Moreover, it jointly addresses the problems of channel and transmission rate selection based on fading and interference concerns. The simulation results confirm the benefits of the proposed architecture when compared with other routing protocols for WMNs, under realistic channel conditions and different networks topologies.
['Kaushik R. Chowdhury', 'Marco Di Felice', 'Luciano Bononi']
A fading and interference aware routing protocol for multi-channel multi-radio wireless mesh networks