Secure and robust wireless communication with intelligent surfaces and rate splitting
S-R3: Secure and Robust RIS-Assisted RSMA under Finite-Resolution Phase Shifts
Networking and Internet Architecture
Summary
Wireless signals can be intercepted by eavesdroppers, making it hard to keep communications private. This paper looks at using smart surfaces that reflect signals and a special way of splitting messages to improve security even when the eavesdropper’s exact location is uncertain. The authors design a method to balance public and private information delivery while considering real hardware limits like phase shift resolution. Their approach adjusts signals and noise carefully to keep information safe and communications reliable.
What this means in practice
- •For wireless network engineers: Design secure wireless downlink systems using intelligent surfaces and rate splitting to improve confidentiality under uncertain eavesdropper information.
- •For telecom infrastructure providers: Integrate finite-resolution configurable surfaces with advanced signal split and noise techniques to enhance secure multiuser communication in cellular networks.
Authors
Ibrahima Sory Diallo, Elhadj Moustapha Diallo, Wang Mi, Mamadou Aliou Diallo, Amayika Kakati
Abstract
This paper investigates a reconfigurable intelligent surface (RIS)-assisted rate-splitting multiple access (RSMA) downlink with imperfect eavesdropper channel state information and finite-resolution RIS phases. The common stream carries public information, while user-specific private streams carry confidential information. For a conservative security assessment, each eavesdropper is allowed to remove the public stream and is given the other private streams as side information. We formulate a robust design of t he transmit precoders, isotropicartificial noise, common-rate allocations, and RIS phases that balances confidential and public throughput under rate and power constraints. Bounded errors in the direct and cascaded eavesdropper channels yield an effective-channel uncertainty bound valid across RIS phase updates. To address the resulting nonconvex problem, we construct conservative leakage bounds and convex inner transmit updates, initialize through a feasibility procedure, and search finite artificial-noise and RIS-phase candidates with explicit feasibility checks. For a fixed artificialnoise power and RIS configuration, the feasible inner iterates have a nondecreasing objective that converges in value, and their successive changes vanish. Accepted outer updates remain feasible and are finite in number. Our code is available at https://github.com/ABM-ADAM/RIS RSMA-secure.