Joint downlink beamforming and power control for 3G WCDMA

The spectral efficiency of the WCDMA downlink can significantly be increased by jointly adjusting beamformers and transmission powers. The design goal is to control individual link capacities with minimum total power. Channel information is assumed to be available at the base station. We propose a computational efficiency strategy which computes the beamforming weights by jointly balancing the instantaneous carrier-to-interference ratios (CINR) measured at each RAKE receiver input. Then, the SINRs at the RAKE output are adjusted by an additional power control step. Potential gains over conventional techniques are shown by numerical simulations.

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