Open AccessCharacterisation of distortion of narrowband signals by linear time‐invariant systems
Author(s) -
Direen Randal H.,
Kuester Edward F.,
Elmansouri Mohamed A.
Publication year - 2017
Publication title -
iet microwaves, antennas and propagation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.555
H-Index - 69
eISSN - 1751-8733
pISSN - 1751-8725
DOI - 10.1049/iet-map.2016.1137
Subject(s) - narrowband , lti system theory , transfer function , bandwidth (computing) , fidelity , distortion (music) , high fidelity , linear system , mathematics , linear approximation , measure (data warehouse) , signal (programming language) , algorithm , computer science , mathematical analysis , physics , acoustics , telecommunications , nonlinear system , engineering , amplifier , electrical engineering , quantum mechanics , database , programming language
The fidelity factor is a commonly used measure of the level of distortion of pulses in ultrawideband systems. In this study, a detailed examination is made of this quantity and how it relates to actual situations of signals transmitted through a linear time‐invariant system. Several examples are considered where the fidelity factor can be evaluated in closed form, or nearly so. In addition, a closed‐form analytical approximation is derived for the fidelity factor in the case where the bandwidth of the input signal is not too large. A number of examples are presented to illustrate the conditions under which this approximation can be expected to be accurate. The error of the approximation is found to be small unless the transfer function of the linear system varies rapidly near the centre frequency of the signal.