A hybrid channel assignment strategy to QoS support of video-streaming over multi-channel ad hoc networks

Currently multi-channel multi-interface ad hoc networks (multi-channel ad hoc networks) have received amount of interest, especially under the context of real-time traffics, such as video applications. Channel assignment is one of the key challenges in multi-channel ad hoc networks. In this paper, based on a representative hybrid channel assignment strategy named as HMCP, a statistic link load based hybrid channel assignment strategy, SLL-HCA, is presented to obtain a better channel assignment metric than that in HMCP. SLL-HCA is based on the HMCP protocol and adopts the statistic link load metric to ensure load balancing in a two-hop neighborhood, and to prevent both the hidden node problem and the exposed node problem. In addition, an enhanced strategy, VE-SLL-HCA, by setting harsher channel assignment conditions and reserving lower interference of routing path for video-streaming traffic than other non-video traffic, is proposed to improve the QoS support of video-streaming over multi-channel ad hoc networks. Simulation results show that SLL-HCA achieves better throughput performance than HMCP in the presence of background traffic including CBR traffic or VBR traffic; and, the PSNR QoS metric for video-streaming is enhanced when using VE-SLL-HCA compared with SLL-HCA and HMCP, which confirms the validity of the proposed strategy for video-streaming traffics. Moreover, the simulation results also indicate that non-video traffic unlikely suffers an unacceptable performance in terms of throughput.