Amplitude Retrieval for Channel Estimation of MIMO Systems With One-Bit ADCs

This letter revisits the channel estimation problem for MIMO systems with one-bit analog-to-digital converters (ADCs) through a novel algorithm-Amplitude Retrieval (AR). Unlike the state-of-the-art methods such as those based on one-bit compressive sensing, AR takes a different approach. It accounts for the lost amplitudes of the one-bit quantized measurements, and performs channel estimation and amplitude completion jointly. This way, the direction information of the propagation paths can be estimated via accurate direction finding algorithms in array processing, e.g., maximum likelihood. The upsot is that AR is able to handle off-grid angles and provide more accurate channel estimates. Simulation results are included to showcase the advantages of AR.

I. Introduction

An effective way to mitigate hardware complexity, cost, and power consumption in commercial large-scale multiple-input multiple-output (MIMO) systems is to use one-bit analog-to-digital converters (ADCs) at both transmitter and receiver. However, with such configuration, each received data sample gives rise to a single bit, i.e., only the sign of that sample is recorded. This challenges many standard channel estimation techniques such as least squares and minimum mean-square error, which were originally designed for finely quantized data. Therefore, developing novel channel estimation algorithms for MIMO systems with one-bit ADCs is of practical and methodological interest.