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Title: A Novel Transceiver Design in Wideband Massive MIMO for Beam Squint Minimization
When using ultra-wideband signaling on massive multiple-input multiple-output (mMIMO) systems, the electromagnetic wave incurs an extra delay (across the array elements) comparable to or larger than the symbol duration, which translates into a shift in beam direction known as the beam squint effect. The beam squinting problem degrades the array gain and reduces the system capacity. This paper proposes a novel transceiver design based on lens antenna subarray and analog subband filters to compensate for the beam squinting effect. Specifically, the proposed design chunks the wideband signal from the phase shifters into groups of narrowband signals and controls their squints through an exhaustive search-based switching/precoding mechanism under the lenses. Furthermore, a simplified, thresholded search-based precoding algorithm is proposed, which demonstrates good performance while significantly minimizing complexity. The proposed system is analyzed in terms of beam gain, complexity, power consumption, and capacity. The numerical results demonstrate significant performance enhancement for the proposed system design as compared to the conventional mMIMO system with an uncompensated beam squinting problem.  more » « less
Award ID(s):
1923857
PAR ID:
10558834
Author(s) / Creator(s):
; ;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
IEEE Transactions on Communications
Volume:
72
Issue:
7
ISSN:
0090-6778
Page Range / eLocation ID:
4509 to 4522
Subject(s) / Keyword(s):
Beam squint effect beam gain, lens antenna subarray (LAS) massive MIMO analog subband filter ultrawideband (UWB) transmission
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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