High SNR capacity of millimeter wave MIMO systems with one-bit quantization

Millimeter wave (mmWave) is a viable technology for future cellular systems. With bandwidths on the order of a gigahertz, high-resolution analog-to-digital converters (ADCs) become a power consumption bottleneck. One solution is to employ very low resolution one-bit ADCs. This paper analyzes the flat fading multiple-input multiple-output (MIMO) channel with one-bit ADC. Bounds on the high signal-to-noise ratio (SNR) capacity are derived for the single-input multiple-output (SIMO) channel and the general MIMO channel. The results show how the number of paths, number of transmit antennas, and number of receive antennas impact the capacity at high SNR.

I. Introduction

Millimeter wave (mmWave) is a technology that can provide high bandwidth communication links in cellular systems. As mmWave uses larger bandwidths, the corresponding sampling rate of the analog-to-digital converter (ADC) scales up. Unfortunately, high speed, high precision (e.g., 8–12 bits) ADCs are costly and power-hungry for portable devices [1], [2]. A possible solution is to use special ADC structures like a time-interleaved ADC (TI-ADC) architecture where a number of low-speed, high-precision ADCs operate in parallel. The main challenge of the TI-ADC is the mismatch among the sub-ADCs in gain, timing and voltage offset which can cause error floors in receiver performance [3], [4]. An alternative solution is to live with ultra low precision ADCs (1–3 bits), which reduces power consumption and cost.