A low-complexity power allocation scheme for distributed wireless links in Rayleigh fading channels with capacity optimization

Abstract

In this paper, a distributed power allocation scheme for wireless links in Rayleigh fast fading environments is proposed. An optimization model is formulated to minimize total transmit powers with constraint conditions that outage probability of each link should be satisfied. A closed-form near optimal solution to the model is presented based on the exploration of power ratio factor at the boundary of system capacity. In terms of the scheme, each link can determine its power ratio factor independently. The inequity problem of the power allocation algorithms in incremental fashion is avoided. Meanwhile the scheme is in low computational complexity due to closed-form solution and it is more time-saving than those schemes in iterative manner. By performance evaluation, we verify our analysis on the optimization model and validate a better result of our scheme in comparison with the counterpart. That is, a larger system capacity is admissible by our method. © Springer-Verlag Berlin Heidelberg 2005.