Paper Info
Title
Simultaneously Transmitting and Reflecting (STAR)-RISs: A Coupled Phase-Shift Model
Abstract
A simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) aided communication system is investigated, where an access point sends information to two users located on each side of the STAR-RIS. Different from current works assuming that the phase-shift coefficients for transmission and reflection can be independently adjusted, which is non-trivial to realize for purely passive STAR-RISs, a coupled transmission and reflection phase-shift model is considered. Based on this model, a power consumption minimization problem is formulated for both non-orthogonal multiple access (NOMA) and orthogonal multiple access (OMA). In particular, the amplitude and phase-shift coefficients for transmission and reflection are jointly optimized, subject to the rate constraints of the users. To solve this non-convex problem, an efficient element-wise alternating optimization algorithm is developed to find a high-quality suboptimal solution, whose complexity scales only linearly with the number of STAR elements. Finally, numerical results are provided for both NOMA and OMA to validate the effectiveness of the proposed algorithm by comparing its performance with that of STAR-RISs using the independent phase-shift model and conventional reflecting/transmitting-only RISs.
Year
DOI
Venue
2022
10.1109/ICC45855.2022.9838767
ICC 2022 - IEEE International Conference on Communications
Keywords
DocType
ISSN
Coefficient design,coupled phase-shift model,reconfigurable intelligent surfaces,simultaneous transmission and reflection
Conference
1550-3607
ISBN
Citations 
PageRank 
978-1-5386-8348-4
0
0.34
References 
Authors
9
4
Name
Order
Citations
PageRank
Yuanwei Liu12162131.65
Xidong Mu221.03
Robert Schober38448488.41
H. V. Poor4254111951.66