Minimum Cost Broadcast in Multi-radio Multi-channel Wireless Mesh Networks

A vast number of broadcasting protocols have been developed for wireless networks. However, most of these protocols assume a single-radio single-channel network model. Employing multiple channels can effectively improve the network capacity in wireless mesh networks. This paper considers minimum cost broadcast (MCB) problem in multi-radio multi-channel wireless mesh networks. We first present the multi-radio multi-channel network model, and then formulate the MCB problem using an integer linear programming model. Our model considers two cases of MCB. In the first case, there already exists a channel assignment in the network, and the formulation minimizes the broadcast cost and reduces interference amongst the adjacent neighbors. In the second case, each node has a set of available channels to be selected. We jointly consider channel assignment and the MCB problem. The joint channel assignment and MCB formulation fully exploits the channel diversity, and also further reduces interference in the network. We propose corresponding centralized and distributed heuristic algorithms to minimize the number of broadcast transmissions with full reliability. In our heuristic algorithms, each node participates in the broadcasting if chosen to maintain the network connectivity or to achieve maximum coverage. Extensive numerical results are presented to demonstrate the performance.