Simultaneous Transmission and Reflection Reconfigurable Intelligent Surface Assisted MIMO Systems

by   Hehao Niu, et al.

In this work, we investigate a novel simultaneous transmission and reflection reconfigurable intelligent surface (RIS)-assisted multiple-input multiple-output downlink system, where three practical transmission protocols, namely, energy splitting (ES), mode selection (MS), and time splitting (TS), are studied. For the system under consideration, we maximize the weighted sum rate with multiple coupled variables. To solve this optimization problem, a block coordinate descent algorithm is proposed to reformulate this problem and design the precoding matrices and the transmitting and reflecting coefficients (TARCs) in an alternate manner. Specifically, for the ES scheme, the precoding matrices are solved using the Lagrange dual method, while the TARCs are obtained using the penalty concave-convex method. Additionally, the proposed method is extended to the MS scheme by solving a mixed-integer problem. Moreover, we solve the formulated problem for the TS scheme using a one-dimensional search and the Majorization-Minimization technique. Our simulation results reveal that: 1) Simultaneous transmission and reflection RIS (STAR-RIS) can achieve better performance than reflecting-only RIS; 2) In unicast communication, TS scheme outperforms the ES and MS schemes, while in broadcast communication, ES scheme outperforms the TS and MS schemes.


page 1

page 2

page 3

page 4


Sum Rate Maximization in STAR-RIS Assisted Full-Duplex Communication Systems

The sum-rate performance of simultaneous transmitting and reflecting rec...

Safeguarding NOMA Networks via Reconfigurable Dual-Functional Surface under Imperfect CSI

This paper investigates the use of the reconfigurable dual-functional su...

Intelligent Omni-Surfaces (IOSs) for the MIMO Broadcast Channel

In this paper, we consider intelligent omni-surfaces (IOSs), which are c...

Over-the-Air Beamforming with Reconfigurable Intelligent Surfaces

Reconfigurable intelligent surface (RIS)-empowered communication is a re...

Safeguarding MIMO Communications with Reconfigurable Metasurfaces and Artificial Noise

Wireless communications empowered by Reconfigurable Intelligent (meta)Su...

Double Intelligent Reflecting Surface-assisted Multi-User MIMO mmWave Systems with Hybrid Precoding

This work investigates the effect of double intelligent reflecting surfa...

Joint Resource Allocation and Configuration Design for STAR-RIS-Enhanced Wireless-Powered MEC

In this paper, a novel concept called simultaneously transmitting and re...