Optimized method of power control during soft handoff in downlink direction of WCDMA systems

In this work an optimized approach of power control during soft handoff in downlink direction of WCDMA systems is proposed which is based on unbalanced power control scheme in which in the downlink direction all base stations in the active set transmit with different power to the MS based on the level of attenuation to the MS. Compared to balanced and unbalanced power control schemes adopted by 3^rd Generation Partnership Program (3GPP) in downlink direction proposed power control scheme during soft handoff reduces the additional interference caused by multiple site transmission and minimizes the overall transmitted power, thus increases the downlink capacity but compromises in the macro-diversity gain due to soft handoff. The proposed scheme is particularly suitable in the environments which face poor propagation attenuation.