Movable Antenna Enabled Symbiotic Radio Systems: An Opportunity for Mutualism

TL;DR

This paper introduces a movable antenna enabled symbiotic radio system that uses antenna movement to optimize and enhance both primary and secondary communication rates, fostering mutual benefits.

Contribution

It proposes a novel movable antenna system for symbiotic radio, optimizing antenna positions to improve both primary and secondary transmission rates.

Findings

Movable antennas significantly improve secondary transmission rates.

The proposed scheme outperforms fixed-position antenna scenarios.

Numerical results confirm the effectiveness of antenna movement in rate enhancement.

Abstract

In this letter, we propose a new movable antenna (MA) enabled symbiotic radio (SR) system that leverages the movement of MAs to maximize both the primary and secondary rates, thereby promoting their mutualism. Specifically, the primary transmitter (PT) equipped with MAs utilizes a maximum ratio transmission (MRT) beamforming scheme to ensure the highest primary rate at the primary user (PU). Concurrently, the backscatter device (BD) establishes the secondary transmission by overlaying onto the primary signal. The utilization of MAs aims to enhance the secondary rate by optimizing the positions of MAs to improve the beam gain at the BD. Accordingly, the beam gains for both MA and fixed-position antenna (FPA) scenarios are analyzed, confirming the effectiveness of the MA scheme in achieving the highest primary and secondary rates. Numerical results verity the superiority of our proposed MA enabled scheme.