Artificial-Noise Aided Design for Movable-Antenna Enabled Physical-Layer Service Integration

2026-04-30

AI Summary

This work addresses the challenge of secure and efficient transmission in physical-layer multicast scenarios where confidential information coexists with non-secure data. By integrating the spatial reconfiguration capability of movable antennas with the interference-shaping ability of artificial noise, the paper proposes a low-complexity joint optimization framework. It analytically reveals the pivotal role of spatial degrees of freedom in artificial noise design and derives a closed-form solution for power allocation between confidential signals and artificial noise. Leveraging structured transmission design, directional characterization of artificial noise, and a block coordinate ascent algorithm, the framework enables synergistic optimization of antenna placement and transmit parameters. The proposed approach significantly enhances secrecy performance while ensuring fast convergence and low computational complexity, with its efficacy validated in movable antenna systems.

Abstract

This paper pioneers a novel scheme for artificial-noise (AN)-aided movable-antenna (MA)-enabled physical-layer service integration (PLSI) to harmonize the simultaneous delivery of multicast and confidential messages. By jointly exploiting the spatial reconfiguration capability of MAs and the interference shaping capability of AN, we aim to enhance secrecy performance while guaranteeing multicast reliability. The joint design of MA positions and transmit variables results in a highly coupled and non-convex optimization problem. To address this, we first provide key insights into the role of spatial degrees of freedom in AN design. We then characterize the AN direction under a structured transmission design and derive a closed-form expression for the AN-to-confidential power allocation ratio, which significantly simplifies the overall design. To solve the resulting problem, we further develop a low-complexity block coordinate ascent (BCA)-based scheme that alternates between transmit design and MA position optimization. Numerical results demonstrate that the proposed scheme achieves significant secrecy performance gains with low computational complexity and fast convergence, highlighting its effectiveness for MA-enabled PLSI systems.

Problem

• movable antenna
• physical-layer service integration
• artificial noise
• secrecy performance
• multicast reliability

Innovation

• movable antenna
• artificial noise
• physical-layer service integration
• secrecy performance
• block coordinate ascent