Optimum power distribution for cellular CDMA downlinks

Power distribution on cellular CDMA downlinks in a slow fading channel environment is studied. We first derive the minimum required power for each connection in order to guarantee its required signal-to-interference ratio (SIR). By comparing the required transmission power for a connection in soft handoff and in hard handoff, we find an optimum area for performing soft handoff in order to best utilize the BS transmission power and maximize the system capacity. Numerical results show that performing soft handoff with properly chosen soft handoff boundary can improve the system capacity.