FIR Beamforming for Frequency-Selective Channels with Linear Equalization

In this letter, we consider transmit beamforming with finite impulse response (FIR) filters for frequency-selective channels and simple linear equalization at the receiver. Since a closed-form solution for the optimum FIR beamforming filters (BFFs) does not seem to exist, an efficient numerical method for their recursive calculation is developed. Our numerical results show that for typical GSM/EDGE channels short FIR BFFs can closely approach the performance of the optimum infinite impulse response (IIR) BFFs derived in [1] and yield significant gains over single-antenna transmission.