Power minimization under real-time source distortion constraints in wireless networks

In multiple access wireless networks with co-channel interference, allocating resources such as transmitted powers and source rates is a task critical to improve performance. In this paper, we introduce a new technique aimed at minimizing the overall transmitted power subject to constraints on the incurred source distortion. The technique is based on the use of real-time source codecs with externally adaptable output rate and rate compatible punctured convolutional (RCPC) channel encoders. We develop an adaptive algorithm to find the optimal power and source rate allocation to the different users according to their channel conditions and under distortion constraints. We present simulation results to show that it is possible to reduce the overall transmitted power significantly with a relatively small distortion increases for some users, and while keeping the network average distortion unchanged.