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Title: The Impact of SAR-ADC Mismatch on Quantized Massive MU-MIMO Systems
Low-resolution analog-to-digital converters (ADCs) in massive multi-user (MU) multiple-input multiple-output (MIMO) wireless systems can significantly reduce the power, cost, and interconnect data rates of infrastructure basestations. Thus, recent research on the theory and algorithm sides has extensively focused on such architectures, but with idealistic quantization models. However, real-world ADCs do not behave like ideal quantizers, and are affected by fabrication mismatches. We analyze the impact of capacitor-array mismatches in successive approximation register (SAR) ADCs, which are widely used in wireless systems. We use Bussgang's decomposition to model the effects of such mismatches, and we analyze their impact on the performance of a single ADC. We then simulate a massive MU-MIMO system to demonstrate that capacitor mismatches should not be ignored, even in basestations that use low-resolution SAR ADCs.  more » « less
Award ID(s):
1717559
PAR ID:
10490329
Author(s) / Creator(s):
;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
Conference record Asilomar Conference on Signals Systems Computers
ISSN:
1058-6393
Format(s):
Medium: X
Location:
Pacific Grove, CA
Sponsoring Org:
National Science Foundation
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