Optimal scheduling in frequency-agile wireless networks

We consider the problem of spectrum-based minimum-length scheduling of point-to-point links in a spatial TDMA (STDMA) wireless network where each node is equipped with a frequency agile radio capable of configuring the bandwidth on a per-slot basis. The problem formulation integrates the activation of multiple sets of links in the network, in a hybrid fashion (both time and frequency domain), while taking into account the Signal-to-Interference and Noise Ratio (SINR) at each receiver. We assume uniform (fixed) transmission power at all nodes and propose an algorithm based on a column generation approach, which allocates a common spectrum band for links that satisfy the SINR constraints at the receivers, and different spectrum bands for interfering links, in order to generate a link schedule that minimizes the schedule length. For the formulated problem, we show that this column generation based approach can converge to a globally optimal solution.