Power-controlled multiple access with a queue-dependent backoff threshold

We propose and evaluate a new distributed algorithm for transmit power control (TPC) in wireless networks. We cast the TPC problem as a dynamic program which captures a fundamental tradeoff between transmit power and delay, and we use its solution to inform our design. The resulting algorithm is reminiscent of existing TPC approaches which seek to have each link maintain a constant signal-to-interference-plus-noise ratio (SINR), but with a key difference: a queue-dependent backoff threshold which allows links to temporarily stop transmitting when the interference grows too large. In high interference scenarios, this difference allows our algorithm to automatically induce a network behavior similar to time-division multiple access (TDMA), without any explicit cross-link coordination. As a result of this behavior, we demonstrate that our algorithm can provide substantial throughput improvements over previous schemes.