Enhanced Transmit Antenna Selection Using OSTBC Scheme with SVD-Based Hybrid Precoding for 5G Millimeter-Wave Communications

Transmit Antenna Selection using Orthogonal Space-Time Block Codes (TAS-OSTBC) aided Millimeter-wave (mmWave) communications is proposed in this paper. The TAS transmitter is characterized by a lower number of Radio Frequency (RF) chains than the number of transmit antennas, hence it is capable of reducing both the energy consumption as well as the transmitter cost. The proposed scheme combines TAS-OSTBC system with Hybrid Analog-Digital Beamforming for 60 GHz mmWave communications and using Hadamard transform. The computer simulation results demonstrate that the TAS-OSTBC scheme with fully digital SVD-based precoding has better Bit Error Rate (BER) performance than that of the conventional TAS system with OSTBC scheme. Furthermore, the error performance is significantly improved by applying Uniform Linear Array (ULA) antennas which improve the system performance as the number of array elements increases due to providing a beamforming gain. It is also found that the BER performance is further improved by applying Hadamard transform with an SNR improvement of about 3dB over the conventional systems without using Hadamard transform.