Codebook Design for Dual-Polarized Ultra-Massive Mimo Communications at Millimeter Wave and Terahertz Bands

Intelligent surfaces at millimeter wave and terahertz band employ large antenna arrays based on advanced metamaterials to realize controllable wireless propagation. Such intelligent surfaces can achieve polarization tuning of electromagnetic waves, which allows polarization diversity under the ultra-massive MIMO communication, in addition to enhancing the beamforming gain and combating the transmission distance limitation. In this work, we analyze the dual-polarized intelligent surface channel and present an efficient precoding solution based on the array-of-subarray architecture that aims to maximize the spectral efficiency. Simulations are performed in comparison to conventional design based on single-polarized channel and obtained results demonstrate an increase in diversity gain with good spectral efficiency.