A Novel Low-Complexity Weight Based Power Allocation Scheme for Distributed OSTBC System

Distributed wireless communication system has been considered as a promising architecture for future wireless communication networks. This paper aims to characterize the power allocation scheme for orthogonal space time block coding in DWCS. Firstly, an optimal method is investigated, which minimizes the upper bound of the ergodic pair-wise symbol error rate, and it is proved to be equivalent to water¿lling based on the knowledge of large-scale fading. In order to reduce the complexity, a low-complexity power allocation method is proposed through approximating the optimization problem. This method assigns a power allocation weight to each distributed base station, and then allocates the power to base stations proportional to these weights. Numerical results show that the performance of this low-complexity algorithm holds close performance with the water¿lling method in most situations.