One-Bit Quantizers for Fading Channels

TL;DR

This paper investigates the impact of one-bit quantizers on the capacity of Rayleigh-fading channels, showing they do not reduce capacity in coherent cases at low SNR but do in noncoherent cases, relevant for low-efficiency communications.

Contribution

It provides a detailed analysis of how one-bit quantization affects channel capacity in fading environments, highlighting differences between coherent and noncoherent channels at low SNR.

Findings

One-bit quantizers do not reduce capacity in coherent fading channels at low SNR.

In noncoherent channels, one-bit quantizers decrease the asymptotic capacity.

The study focuses on low spectral efficiency regimes relevant for Spread Spectrum and Ultra-Wideband systems.

Abstract

We study channel capacity when a one-bit quantizer is employed at the output of the discrete-time average-power-limited Rayleigh-fading channel. We focus on the low signal-to-noise ratio regime, where communication at very low spectral efficiencies takes place, as in Spread Spectrum and Ultra-Wideband communications. We demonstrate that, in this regime, the best one-bit quantizer does not reduce the asymptotic capacity of the coherent channel, but it does reduce that of the noncoherent channel.