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Title: Finite-Alphabet Wiener Filter Precoding for mmWave Massive MU-MIMO Systems
Power consumption of multiuser (MU) precoding is a major concern in all-digital massive MU multiple-input multiple-output (MIMO) basestations with hundreds of antenna elements operating at millimeter-wave (mmWave) frequencies. We propose to replace part of the linear Wiener filter (WF) precoding matrix by a Finite-Alphabet WF Precoding (FAWP) matrix, which enables the use of low-precision hardware that consumes low power and area. To minimize the performance loss of our approach, we present methods that efficiently compute mean-square error (MSE)-optimal FAWP matrices. Our results show that FAWP matrices are able to approach infinite-precision error-rate and error vector magnitude performance with only 3-bit precoding weights, even when operating under realistic mmWave propagation conditions. Hence, FAWP is a promising approach to substantially reduce power consumption and silicon area in all-digital mmWave massive MU-MIMO systems.  more » « less
Award ID(s):
1652065 1740286 1717559
NSF-PAR ID:
10142833
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Asilomar Conference on Signals, Systems, and Computers
Page Range / eLocation ID:
178 to 183
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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