Optimal joint routing and scheduling in wireless mesh networks with smart antennas

We present a cross-layer optimization framework for wireless mesh networks; we assume nodes are equipped with smart antenna and techniques such as beam-forming, spatial division multiple access and spatial division multiplexing are considered. These techniques provide interference suppression, capability to communicate with several nodes simultaneously and higher transmission data rates, respectively. By integrating different constraints from MAC and network layers, a mathematical formulation of the problem is presented. It is shown that the resulted directive, multiple access and multiplexing gain combined with optimal link scheduling effectively increase both the spectrum spatial reuse and the capacity of the links and thus, enhance the achievable system throughput. Since the optimization problem is a complex combinatorial one, the optimal LP solution is approached by a Column Generation decomposition method. The numerical results for different network topologies with various node densities, transmission ranges, traffics and number of antennas are provided, in which system activation time is reduced up to 86.9% by employing smart antenna techniques.