# Gaussian Multiple Access Channels with One-Bit Quantizer at the Receiver

## TL;DR

This paper investigates the capacity region of a Gaussian multiple access channel with a one-bit ADC at the receiver, revealing that optimal inputs are discrete and providing bounds on their complexity.

## Contribution

It establishes that optimal input distributions are discrete and derives bounds on their number of mass points for channels with one-bit quantization.

## Key findings

- Optimal input distributions are discrete.
- Upper bounds on the number of mass points are derived.
- Capacity region characterization under one-bit quantization.

## Abstract

The capacity region of a two-transmitter Gaussian multiple access channel (MAC) under average input power constraints is studied, when the receiver employs a zero-threshold one-bit analog-to-digital converter (ADC). It is proved that the input distributions of the two transmitters that achieve the boundary points of the capacity region are discrete. Based on the position of a boundary point, upper bounds on the number of the mass points of the corresponding distributions are derived.