"Locking" Dynamics and Mitigation Schemes in Distributed Power Control for Wireless Networks

Power-controlled multiple access (PCMA) is a distributed algorithm for transmitter power control of autonomous communication links in wireless networks. By allowing links to trade off transmission power for packet delay, PCMA has been demonstrated to outperform standard approaches (e.g., the Foschini-Miljanic constant signal-to-interference ratio algorithm) in terms of maximum throughput, especially in cases of high interference. However, recent experiments have revealed that as interference grows higher, links using PCMA may "lock" into inefficient power evolution patterns which compromise network performance. In this paper, we explore this locking dynamic, which is caused by the highly non-linear nature of PCMA. We then propose simple randomization-based mitigation mechanisms to alleviate locking behavior, and we demonstrate that these mechanisms can substantially improve PCMA efficiency.