Capacity of Multiple One-Bit Transceivers in a Rayleigh Environment

TL;DR

This paper derives the capacity limits of large-scale systems with one-bit transceivers in Rayleigh environments, showing how capacity depends on the ratio of receivers to transmitters and SNR, with practical approximations.

Contribution

It provides a novel analytical expression for the capacity of systems with many one-bit transceivers in Rayleigh fading, including simple approximations and saturation conditions.

Findings

Capacity per transmitter is bounded by min(1, α).

At high SNR, capacity reaches 1 only if α > 1.24.

Derived expressions accurately approximate capacity for small M.

Abstract

We analyze the channel capacity of a system with a large number of one-bit transceivers in a classical Rayleigh environment with perfect channel information at the receiver. With $M$ transmitters and $N=\alpha M$ receivers, we derive an expression of the capacity per transmitter $\mathcal{C}$, where $\mathcal{C}\leq\min(1,\alpha)$, as a function of $\alpha$ and signal-to-noise ratio (SNR) $\rho$, when $M\to\infty$. We show that our expression is a good approximation for small $M$, and provide simple approximations of $\mathcal{C}$ for various ranges of $\alpha$ and SNR $\rho$. We conclude that at high SNR, $\mathcal{C}$ reaches its upper limit of one only if the ratio $\alpha>1.24$. Expressions for determining when $\mathcal{C}$ "saturates" as a function of $\alpha$ and $\rho$ are given.