On the hybrid beamforming with shared array antenna for mmWave MIMO-OFDM systems

Along with the attention drawn to the millimeter-wave frequency bands for the drastically increased data rate support for the next generation (5G) mobile communications, the hybrid beamforming architectures combining analog beamforming and digital precoding have been investigated as potential candidates to provide good compromise between the complexity and the performance. Among the different hybrid beamforming architectures, the architecture with so-called shared array antenna is analyzed with respect to the peak-to-mean envelope power ratio over antenna elements and the total average transmission power constraint upon multi-beam transmissions. It is shown that the non-trivial normalization coefficients should be applied to the hybrid beamforming architecture under consideration to achieve the average transmission power within the total power constraint. Taking into account the total power normalization for the hybrid beamforming architecture with shared array antenna, various simulation results are provided to show the performance of the multi-beam transmission diversity against the single-beam analog beamforming.