Effective number of samples and pseudo-random nonlinear distortions in digital OFDM coded signal

TL;DR

This paper introduces the concept of effective number of samples to accurately model and analyze pseudo-random nonlinear distortions in digital OFDM signals caused by converters.

Contribution

It proposes a new quantity, effective number of samples, for better modeling of distortions in digital signals, replacing total sample count in analysis.

Findings

Derived expressions for autocorrelation and power of distortions

Effective number of samples accurately characterizes digital signal distortions

Provides a probabilistic model for signal transition and distortion analysis

Abstract

This paper concerns theoretical modeling of degradation of signal with OFDM coding caused by pseudo-random nonlinear distortions introduced by an analog-to-digital or digital-to-analog converter. A new quantity, effective number of samples, is defined and used for derivation of accurate expressions for autocorrelation function and the total power of the distortions. The derivation is based on probabilistic model of the signal and its transition probability. It is shown, that for digital (discrete and quantized) signals the effective number of samples replaces the total number of samples and is the proper quantity defining their properties.