MIMO beamforming architecture in millimeter wave communication systems

The recent traffic explosion in wireless communication systems have drawn great attention to the large amount of the underutilized spectrum in millimeter-wave (mm Wave) communication systems as a potential candidate for achieving ten to hundred times more capacity as compared to the current 4G communication system. Designing of an appropriate beamforming scheme in order to overcome the unfavourable path loss is one of the key enabler for communication at 60 GHz frequency band. Multiple antennas in 60 GHz using single input single output (SISO) can only provide diversity and signal to noise ratio (SNR) gain, so multiple input multiple output (MIMO) beamforming is indispensable in further increasing the system throughput. In this work, we propose an efficient MIMO beamforming algorithm to maximize the channel capacity for mm Wave channel. Our research focuses on splitting the large antenna array into 2x2 or higher-order MIMO system, with the objective to maximize the product of the singular values of the partitioned channel matrix, resulting in optimal beamforming vectors, thus maximizing the channel capacity. By applying the proposed MIMO beamforming algorithm, there is at least 50% increase in capacity of the system to that of SISO beamforming. Simulation is done for both Rayleigh fading and mm Wave channel and is focused on optimizing the beamforming vectors alternatively at the transmitter and receiver. The proposed algorithm is highly effective in high SNR scenarios.