Hybrid precoding for cluster-based multi-carrier beam division multiple access in terahertz wireless communications

Terahertz (THz) wireless communication has the capability to connect massive devices using its ultra-large spectrum resource. We propose a hybrid precoding scheme for the cluster-based multi-carrier beam division multiple access (MC-BDMA) to enable THz massive connections. Both the inter-beam interference and inter-band power leakage in this system are considered. A mathematical model is established to analyze and reduce their effects on the THz signal transmission. By considering the peculiarities of THz channels and characteristics of THz hardware components, we further propose a three-step hybrid precoding algorithm with low complexity, where the received signal power enhancement, the inter-beam interference elimination, and the inter-band power leakage suppression are conducted in succession. Simulation results are presented to demonstrate the high spectrum efficiency and high energy efficiency of our proposed algorithm, especially in the massive-connection scenarios.