# Massive MU-MIMO-OFDM Uplink with Direct RF-Sampling and 1-Bit ADCs

## TL;DR

This paper explores the use of direct RF-sampling with 1-bit ADCs in massive MU-MIMO-OFDM uplink systems, demonstrating low error and high constellation support through analytical error analysis.

## Contribution

It introduces an analytical framework for evaluating EVM in direct RF-sampling MU-MIMO-OFDM systems with 1-bit ADCs, highlighting their potential for high-performance uplink communication.

## Key findings

- Low EVM achieved with 1-bit ADCs
- Supports high-order modulation schemes
- Analytical expression for EVM using Bussgang's theorem

## Abstract

Advances in analog-to-digital converter (ADC) technology have opened up the possibility to directly digitize wideband radio frequency (RF) signals, avoiding the need for analog down-conversion. In this work, we consider an orthogonal frequency-division multiplexing (OFDM)-based massive multi-user (MU) multiple-input multiple-output (MIMO) uplink system that relies on direct RF-sampling at the base station and digitizes the received RF signals with 1-bit ADCs. Using Bussgang's theorem, we provide an analytical expression for the error-vector magnitude (EVM) achieved by digital down-conversion and zero-forcing combining. Our results demonstrate that direct RF-sampling 1-bit ADCs enables low EVM and supports high-order constellations in the massive MU-MIMO-OFDM uplink.