TY - GEN
T1 - Two-Way Communications via Reconfigurable Intelligent Surface
AU - Atapattu, Saman
AU - Fan, Rongfei
AU - Dharmawansa, Prathapasinghe
AU - Wang, Gongpu
AU - Evans, Jamie
N1 - Publisher Copyright:
© 2020 IEEE.
PY - 2020/5
Y1 - 2020/5
N2 - The novel reconfigurable intelligent surface (RIS) is an emerging technology which facilitates high spectrum and energy efficiencies in Beyond 5G and 6G wireless communication applications. Against this backdrop, this paper investigates two-way communications via reconfigurable intelligent surfaces (RISs) where two users communicate through a common RIS. We assume that uplink and downlink communication channels between two users and the RIS can be reciprocal. We first obtain the optimal phase adjustment at the RIS. We then derive the exact outage probability and the average throughput in closed-forms for single-element RIS. To evaluate multiple-element RIS, we first introduce a gamma approximation to model a product of Rayleigh random variables, and then derive approximations for the outage probability and the average throughput. For large average signal-to-interference-plus-noise ratio (SINR) \rho, asymptotic analXsis also shows that the outage decreases at the rate (\log(\rho)/\rho) where L is the number of elements, whereas the throughput increases with the rate \log(\rho).
AB - The novel reconfigurable intelligent surface (RIS) is an emerging technology which facilitates high spectrum and energy efficiencies in Beyond 5G and 6G wireless communication applications. Against this backdrop, this paper investigates two-way communications via reconfigurable intelligent surfaces (RISs) where two users communicate through a common RIS. We assume that uplink and downlink communication channels between two users and the RIS can be reciprocal. We first obtain the optimal phase adjustment at the RIS. We then derive the exact outage probability and the average throughput in closed-forms for single-element RIS. To evaluate multiple-element RIS, we first introduce a gamma approximation to model a product of Rayleigh random variables, and then derive approximations for the outage probability and the average throughput. For large average signal-to-interference-plus-noise ratio (SINR) \rho, asymptotic analXsis also shows that the outage decreases at the rate (\log(\rho)/\rho) where L is the number of elements, whereas the throughput increases with the rate \log(\rho).
KW - Outage probability
KW - reconfigurable intelligent surface (RIS)
KW - throughput
KW - two-way communications
UR - http://www.scopus.com/inward/record.url?scp=85087276736&partnerID=8YFLogxK
U2 - 10.1109/WCNC45663.2020.9120479
DO - 10.1109/WCNC45663.2020.9120479
M3 - Conference contribution
AN - SCOPUS:85087276736
T3 - IEEE Wireless Communications and Networking Conference, WCNC
BT - 2020 IEEE Wireless Communications and Networking Conference, WCNC 2020 - Proceedings
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2020 IEEE Wireless Communications and Networking Conference, WCNC 2020
Y2 - 25 May 2020 through 28 May 2020
ER -