Movable Antenna Assisted OAM Wireless Communications With Misaligned Transceiver

TL;DR

This paper introduces a movable antenna scheme to align transceivers in OAM wireless communications, effectively mitigating misalignment issues and enhancing spectrum efficiency.

Contribution

It proposes a novel movable antenna-assisted method to correct UCA misalignment in OAM wireless systems, improving signal recovery and spectrum utilization.

Findings

Significant improvement in spectrum efficiency with the proposed scheme

Effective estimation and feedback of UCA rotation angle

Enhanced signal recovery despite transceiver misalignment

Abstract

The vortex electromagnetic wave carried by multiple orthogonal orbital angular momentum (OAM) modes in the same frequency band can be applied to the field of wireless communications, which greatly increases the spectrum efficiency. The uniform circular array (UCA) is the classical structure to generate and receive vortex electromagnetic waves with multiple OAM-modes. However, when the transmit and receive UCAs are misaligned, there will be interference among the OAM-modes and the signal cannot be recovered at the receiver. In order to solve this problem, we propose movable antenna (MA) assisted OAM wireless communications scheme. We estimate the rotation angle between transmit and receive UCAs and feed it back to the transmitter. Then, the MA at the transmitter adjusts the rotation angle to achieve alignment of the UCA at both the receiver and transmitter. Simulation results show that our scheme can significantly improve the spectrum efficiency.