Flexible Self-Alignment Reception for OAM-Based Large-Capacity Wireless Backhaul Links

Due to the beam divergence of the Orbital Angular Momentum (OAM) Radio Frequency (RF) waves, the transmission distance is quite limited. Considering actual engineering constraints, it is difficult and costly to deploy conventional coplanar arrays on the station towers to receive OAM beams. In this paper, a flexible self-alignment reception scheme with General Non-uniform Array (GNA) is proposed to solve this problem. The antennas are distributed around the propagation axis without strict coplanar and uniform requirement, so that the phase plane covered by this distributed array can be large enough to receive the divergent vortex beams. With credible analysis and experiments, it can be confirmed that the OAM-based long-distance wireless backhaul links can be acquired.