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Title: Joint Downlink and Uplink Optimization for RIS-Aided FDD MIMO Communication Systems
This paper investigates reconfigurable intelligent surface (RIS)-aided frequency division duplexing (FDD) communication systems. Since the downlink and uplink signals are simultaneously transmitted in FDD, the phase shifts at the RIS should be designed to support both transmissions. Considering a single-user multiple-input multiple-output system, we formulate a weighted sum-rate maximization problem to jointly maximize the downlink and uplink system performance. To tackle the non-convex optimization problem, we adopt an alternating optimization (AO) algorithm, in which two phase shift optimization techniques are developed to handle the unit-modulus constraints induced by the reflection coefficients at the RIS. The first technique exploits the manifold optimization-based algorithm, while the second uses a lower-complexity AO approach. Numerical results verify that the proposed techniques rapidly converge to local optima and significantly improve the overall system performance compared to existing benchmark schemes.  more » « less
Award ID(s):
2107182 2030029
PAR ID:
10598718
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
IEEE Transactions on Wireless Communications
Volume:
23
Issue:
8
ISSN:
1536-1276
Page Range / eLocation ID:
9059 to 9071
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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