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.

翻译：大规模多用户（MU）多输入多输出（MIMO）无线系统中的低分辨率模数转换器（ADC）能够显著降低基础设施基站的功耗、成本和互连数据传输速率。因此，近年来的理论和算法研究广泛关注此类架构，但均采用理想化量化模型。然而，实际ADC的行为与理想量化器存在差异，且会受到制造失配的影响。本文分析了广泛应用于无线系统的逐次逼近寄存器（SAR）ADC中电容阵列失配的影响。我们采用Bussgang分解对失配效应进行建模，并分析了单个ADC性能受此类失配的影响程度。进一步通过大规模MU-MIMO系统仿真证明：即使在使用低分辨率SAR ADC的基站中，电容失配效应也不应被忽视。