A cross-layer approach to end-to-end routing and SINR-based scheduling in multi-hop wireless networks

In this paper we study the problem of jointly controlling routing and transmission scheduling in spatial TDMA (STDMA)-based multihop wireless networks, with the goal of determining the minimum-length schedule that satisfies a given end-to-end traffic demand. We present a cross-layer formulation of the problem that incorporates multi-path routing at the network layer, while concurrently generating matchings to address the media-access control problem. Each such matching consists of a set of links that can simultaneously be active, without violating the specified signal-to-interference-and-noise ratio (SINR) requirement. We formulate our problem as one of mixed integer-linear programming, and we show that our column generation approach converges to a globally optimal solution. After considering a problem formulation that is restricted to the use of the same RF transmission power by all nodes, we extend our model to incorporate power adaptation, and demonstrate the resulting improvement in performance. We also discuss the insights that can be gained about the influence of power control, and spatial reuse on network performance.