Hybrid beamforming for link recovery in millimeter wave communications

This paper presents a novel dual-beam recovery method for blocked links in millimeter wave communications. Namely, transmit diversity is achieved here by using a hybrid beamforming technique to establish recovery beams in Rician channels. Once the direct line-of-sight link is blocked, equal gain combining is applied to the incoming signals from the dual-beams, i.e., to compensate for signal degradation. The proposed method provides near-instantaneous link recovery without the need for iterative beam scanning. Simulations show that the proposed method yields enhanced received signal levels across various blockage parameters versus single beam recovery schemes.