A Remark on Channels with Transceiver Distortion

TL;DR

This paper analyzes channels with transceiver distortion using generalized mutual information, establishing a canonical structure that maximizes information transfer and clarifies the role of Bussgang's decomposition in linear processing.

Contribution

It introduces a canonical transceiver structure that maximizes GMI and relates Bussgang's decomposition to this optimal processing.

Findings

The canonical structure involves MMSE estimation before decoding.

Bussgang's decomposition aligns with GMI under linear output processing.

Maximizing GMI improves understanding of transceiver distortion effects.

Abstract

Information transmission over channels with transceiver distortion is investigated via generalized mutual information (GMI) under Gaussian input distribution and nearest-neighbor decoding. A canonical transceiver structure in which the channel output is processed by a minimum mean-squared error estimator before decoding is established to maximize the GMI, and the well-known Bussgang's decomposition is shown to be a heuristic that is consistent with the GMI under linear output processing.