SDP-based Approach for Channel Assignment in Multi-radio Wireless Networks

Hieu Dinh Computer Science & Engineering Dept. U. of Connecticut Storrs, CT, 06269. [email protected] Yoo-Ah Kim Computer Science & Engineering Dept. U. of Connecticut Storrs, CT, 06269. [email protected] Seungjoon Lee AT&T Labs – Research Florham Park, NJ 07932. [email protected] Minho Shin Computer Science Dept. U. of Maryland College Park, MD, 20740. [email protected] Bing Wang Computer Science & Engineering Dept. U. of Connecticut Storrs, CT, 06269. [email protected] ABSTRACT We consider the following channel assignment problem in multiradio multi-channel wireless networks: Given a wireless network where k orthogonal channels are available and each node has multiple wireless interfaces, assign a channel to each link so that the total number of conflicts is minimized. We present an integer semidefinite programming formulation for the problem and show that it is equivalent to an optimal channel assignment. By relaxing integrality constraints, we can find a lowerbound on the optimal channel assignment. We develop several channel assignment algorithms based on the solution to the SDP relaxation. Our results from numerical evaluations and packet-level simulations show that our SDP-based rounding algorithms outperform other simple heuristics (up to 200% improvement in throughput). In particular, our schemes achieve even larger performance improvement when nodes have different numbers of interfaces, in which simple heuristics (e.g., greedy) do not perform well.