Energy efficient joint scheduling and power control for wireless sensor networks

We investigate the problem of energy efficiency in TDMA link scheduling with transmission power control using a realistic SINR-based interference model, given packets of a set of links to be transmitted within a latency bound. First we formulate a fundamental optimization problem (TJSPC) that provides tunable tradeoffs between energy, throughput and latency through a single parameter beta. We present both exponential and polynomial complexity solutions to this problem and evaluate their performance. Our results, show that for moderate traffic loads, with appropriate tuning of parameters, major energy savings can be obtained without significantly sacrificing throughput. We then investigate the scheduling and power control problem with the objective of minimizing the total transmission energy cost under the constraint that all transmission requests are satisfied (JSPC-TR). We present an iterative approach to solve JSPC-TR that leverages the heuristics for TJSPC and converges rapidly to the setting of beta which achieves energy efficiency while guaranteeing data delivery.