Simultaneously Transmitting And Reflecting (STAR) RIS Aided Wireless Communications
By Xidong Mu, Yuanwei Liu, Li Guo, Jiaru Lin, Robert Schober. IEEE Transactions on Wireless Communications, 2021
878 citations recorded by the source corpus.
The novel concept of simultaneously transmitting and reflecting (STAR) reconfigurable intelligent surfaces (RISs) is investigated, where the incident wireless signal is divided into transmitted and reflected signals passing into both sides of the space surrounding the surface, thus facilitating a full-space manipulation of signal propagation. Based on the introduced basic signal model of ‘STAR’, three practical operating protocols for STAR-RISs are proposed, namely energy splitting (ES), mode switching (MS), and time switching (TS). Moreover, a STAR-RIS aided downlink communication system is considered for both unicast and multicast transmission, where a multi-antenna base station (BS) sends information to two users, i.e., one on each side of the STAR-RIS. A power consumption minimization problem for the joint optimization of the active beamforming at the BS and the passive transmission and reflection beamforming at the STAR-RIS is formulated for each of the proposed operating protocols, subject to communication rate constraints of the users. For ES, the resulting highly-coupled non-convex optimization problem is solved by an iterative algorithm, which exploits the penalty method and successive convex approximation. Then, the proposed penalty-based iterative algorithm is extended to solve the mixed-integer non-convex optimization problem for MS. For TS, the optimization problem is decomposed into two subproblems, which can be consecutively solved using state-of-the-art algorithms and convex optimization techniques. Finally, our numerical results reveal that: 1) the TS and ES operating protocols are generally preferable for unicast and multicast transmission, respectively; and 2) the required power consumption for both scenarios is significantly reduced by employing the proposed STAR-RIS instead of conventional reflecting/transmiting-only RISs.
Subfields: Aerospace Engineering, Electrical and Electronic Engineering, Ocean Engineering
View Paper: https://www.semanticscholar.org/paper/21a4f5ef3666aae89bdff1e8280dacade119b390
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Aerospace Engineering
- Yuanwei Liu
- Robert Schober
- Xidong Mu
- Naofal Al-Dhahir
- Zijian Zhang
- Zhiguo Ding
- Ekram Hossain
- Xuemin Shen
In Electrical and Electronic Engineering
- Yuanwei Liu
- Robert Schober
- Naofal Al-Dhahir
- Xidong Mu
- Zhiguo Ding
- H. Vincent Poor
- Ekram Hossain
- Shuowen Zhang
In Ocean Engineering
Citations in the corpus
- An Overview of Signal Processing Techniques for RIS/IRS-Aided Wireless Systems (2021, neutral): “ously realize reflections and refractions in order to guarantee omni-coverage performance [265]–[268].”
- Evolution of NOMA Toward Next Generation Multiple Access (NGMA) for 6G (2021, background): “Compared to reflecting-only RIS, the signal incident on STARRIS can be transmitted and reflected to both sides [110], [111].”
- Active RIS vs. Passive RIS: Which Will Prevail in 6G? (2021, background): “In this paper, we focus on studying reflective active RISs, while the investigation of transmissive active RISs is left for future work [25]–[27].”