# Massive MU-MIMO-OFDM Downlink with One-Bit DACs and Linear Precoding

## TL;DR

This paper evaluates the downlink performance of massive MU-MIMO-OFDM systems with 1-bit DACs, showing that large antenna arrays can compensate for the coarse quantization and achieve satisfactory performance.

## Contribution

It provides a performance analysis of massive MU-MIMO-OFDM with 1-bit DACs using Bussgang's theorem and develops a lower bound on sum-rate throughput, highlighting the potential of large antenna arrays.

## Key findings

- Performance with 1-bit DACs improves with more antennas.
- Linear precoding can effectively mitigate quantization effects.
- Satisfactory performance is achievable with sufficiently large antenna arrays.

## Abstract

Massive multiuser (MU) multiple-input multiple- output (MIMO) is foreseen to be a key technology in future wireless communication systems. In this paper, we analyze the downlink performance of an orthogonal frequency division multiplexing (OFDM)-based massive MU-MIMO system in which the base station (BS) is equipped with 1-bit digital-to-analog converters (DACs). Using Bussgang's theorem, we characterize the performance achievable with linear precoders (such as maximal-ratio transmission and zero forcing) in terms of bit error rate (BER). Our analysis accounts for the possibility of oversampling the time-domain transmit signal before the DACs. We further develop a lower bound on the information-theoretic sum-rate throughput achievable with Gaussian inputs. Our results suggest that the performance achievable with 1-bit DACs in a massive MU-MIMO-OFDM downlink are satisfactory provided that the number of BS antennas is sufficiently large.