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Title: Design Trade-offs for Decentralized Baseband Processing in Massive MU-MIMO Systems
Massive multi-user (MU) multiple-input multiple-output (MIMO) provides high spectral efficiency by means of spatial multiplexing and fine-grained beamforming. However, conventional base-station (BS) architectures for systems with hundreds of antennas that rely on centralized baseband processing inevitably suffer from (i) excessive interconnect data rates between radio-frequency circuitry and processing fabrics, and (ii) prohibitive complexity at the centralized baseband processor. Recently, decentralized baseband processing (DBP) architectures and algorithms have been proposed, which mitigate the interconnect bandwidth and complexity bottlenecks. This paper systematically explores the design trade-offs between error-rate performance, computational complexity, and data transfer latency of DBP architectures under different system configurations and channel conditions. Considering architecture, algorithm, and numerical precision aspects, we provide practical guidelines to select the DBP architecture and algorithm that are able to realize the full benefits of massive MU-MIMO in the uplink and downlink.  more » « less
Award ID(s):
1717218 1717559
NSF-PAR ID:
10202731
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
2019 IEEE 53rd Asilomar Conference on Signals, Systems and Computers
Page Range / eLocation ID:
906 to 912
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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