Paper Info
Title
Joint Transmit Precoding and Reconfigurable Intelligent Surface Phase Adjustment: A Decomposition-Aided Channel Estimation Approach
Abstract
Reconfigurable intelligent surfaces (RISs), consisting of many low-cost elements that reflect the incident waves by an adjustable phase shift, have attracted sudden attention for their potential of reconfiguring the signal propagation environment and enhancing the performance of wireless networks. The passive nature of RISs is indeed beneficial, but the lack of radio frequency (RF) chains at the RIS has made channel estimation extremely challenging. We face this challenge by proposing a joint channel estimation and transmit precoding framework for RIS-aided multiple-input multiple-output (MIMO) systems. Specifically, the effective cascaded channel of the reflected transmitter-RIS-receiver link is decomposed into multiple subchannels, each of which corresponds to a single RIS element. Then our joint RIS-transmitter precoding model is formulated for the individual subchannels of each reflecting element. Finally, we develop a two-stage precoding design for successively determining the required phase shifts of each reflecting element of the RIS and the digital baseband precoder of the transmitter, only relying on the channel state information (CSI) of the subchannels. The performance of the proposed subchannel estimation and joint precoding method is evaluated by extensive simulations. Our numerical results show that the proposed designs provide an attractive solution to RIS-aided MIMO systems.
Year
DOI
Venue
2021
10.1109/TCOMM.2020.3034259
IEEE Transactions on Communications
Keywords
DocType
Volume
Reconfigurable intelligent surface,channel estimation,precoding,MIMO,channel decomposition
Journal
69
Issue
ISSN
Citations 
2
0090-6778
21
PageRank 
References 
Authors
0.55
34
4
Name
Order
Citations
PageRank
Zhengyi Zhou1273.08
ning249661.98
Zhaocheng Wang32359147.30
Lajos Hanzo410889849.85