Cross-layer optimization of wireless multi-hop networks with network coding

In this paper we present a cross-layer algorithm for joint optimization of congestion control, routing, and scheduling in wireless multi-hop networks with network coding. We introduce virtual flow variables in the formulation of capacity region of the networks. The utility maximization problem subject to constraints on the capacity region is solved using dual decomposition and subgradient method, based on which a new queuing model is obtained and which also can result in a cross-layer algorithm for distributed implementation. The new queuing model can facilitate coding operations and reduce coding complexity. Simulation results show that network coding in the proposed joint optimization algorithm can interact adaptively and optimally with other components in different layers, and thus yield higher performance than the routing scheme without network coding.