# MMSE precoder for massive MIMO using 1-bit quantization

## TL;DR

This paper introduces a novel MMSE precoder design for massive MIMO systems with 1-bit DACs and ADCs, effectively mitigating quantization distortions by considering non-linearities and optimizing a two-stage precoding process.

## Contribution

It presents a new linear MMSE precoder that accounts for 1-bit quantization non-linearities, improving performance in massive MIMO downlink scenarios.

## Key findings

- The proposed precoder outperforms previous linear precoders in BER performance.
- The design effectively mitigates quantization distortions in low-resolution massive MIMO systems.
- Simulation results validate the efficiency of the two-stage precoding approach.

## Abstract

We propose a novel linear minimum-mean-squared-error (MMSE) precoder design for a downlink (DL) massive multiple-input-multiple-output (MIMO) scenario. For economical and computational efficiency reasons low resolution 1-bit digital-to-analog (DAC) and analog-to-digital (ADC) converters are used. This comes at the cost of performance gain that can be recovered by the large number of antennas deployed at the base station (BS) and an appropiate precoder design to mitigate the distortions due to the coarse quantization. The proposed precoder takes the quantization non-linearities into account and is split into a digital precoder and an analog precoder. We formulate the two-stage precoding problem such that the MSE of the users is minimized under the 1-bit constraint. In the simulations, we compare the new optimized precoding scheme with previously proposed linear precoders in terms of uncoded bit error ratio (BER).