Optimal Power Control for Multi-Hop Software Defined Radio Networks

Software defined radio (SDR) is a revolution in radio technology that promises unprecedented flexibility in radio communications and is viewed as an enabling technology for dynamic spectrum access. This paper investigates how to support user communication sessions by jointly considering power control, scheduling, and flow routing for an SDR-based multi-hop wireless network. We develop a formal mathematical model for scheduling feasibility under the influence of power control. This model extends existing protocol interference model for wireless networks and can be used for a broad class of problems where power control (and thus transmission range and interference range) is part of the optimization space. We formulate a cross-layer optimization problem encompassing power control, scheduling, and flow routing. Subsequently, we develop an efficient solution procedure based on branch-and-bound technique and convex hull relaxation. Using simulation results, we demonstrate the efficacy of the solution procedure and offer insights on the impact of power control on scheduling feasibility, bandwidth efficiency, and bandwidth-footprint product (BFP).