Optimizing the downlink power of macrodiversity antennas in an indoor DS-CDMA system

This paper investigates the downlink performance of an indoor DS-CDMA system that performs an optimization on the transmit power of macrodiversity antennas. Our results show that the power optimization significantly increases the system capacity. We present a global optimization strategy that allocates power at the various macrodiversity antennas so that the average of all users' BERs is minimized. In practice, the complexity of this global optimization problem is reduced as many of the links are extremely weak and can be removed from the optimization. Our simulation results demonstrate that when compared to traditional soft handoff power allocation, our optimization algorithm increases the capacity for a given quality of service. The simulation results indicate downlink capacity gains on the order of 10-20%.