A Downlink Beamforming with SINR Balance in Frequency Selective Fading Environment

A downlink beamforming (DLBF) realizing a balanced SINR at mobiles in the frequency-selective fading environment is proposed. Because of the necessity to equalize the temporally dispersed channel, the DLBF forms a joint beamforming, equalization and power control. The proposed algorithm extends the Schubert-Boche (SB) algorithm [1] which is based on the frequency-flat fading environment. As a typical application example of the proposed algorithm, a linear precoding on the DS-CDMA platform is considered, and its general SINR expressions are derived for both complete and partial channel state information (CSI) cases so that they can be plugged into the extended SB algorithm. Finally, statistical computer simulations are carried out to demonstrate characteristics of the proposed algorithm