Research
Cyclostationary-Signal Detection and Parameter Estimation
Second- and Higher-Order Cyclostationarity
Summary – Signals exhibiting second- and higher-order cyclostationarity have probabilistic parameters such as second- and higher-order moments and cumulants that are almost-periodic functions of time. They include virtually all man-made communications signals. For such class of signals, several contributions have been given in the most important signal processing topics. Specifically, the linear time-invariant and almost-periodically time-variant filtering, [C11], [J5], the time-variant liner filtering [C14], [C15], the nonlinear filtering [C12], the sampling [J5], [J6], the Rice’s representation [J7], the multirate processing of discrete-time signal [C13], [J8], the identification of linear time-invariant systems [C19], [J10], and the spectral estimation [J11] have been considered. In [J21], a survey of the literature on cyclostationarity up to year 2005 is presented. A survey of the literature from 2006 to 2015 is presented in [J36].
Summary – Two classes of nonstationary signals extending the class of the almost-cyclostationary (ACS) signals have been introduced and characterized: the Generalized Almost-CycloStationary (GACS) signals [C16], [J9], [J15], [J16], [J17], [J25], [J27], [J30], and the Spectrally Correlated (SC) signals [C28], [J18], [C41], [J29], [J31]. Such signals can arise form several linear time-variant processing of almost-cyclostationary signals [C17], [C21], [C24], [C25], [C29], [J15], [J16] and are shown to be useful in modelling the received signals in wide-band (wireless) communication systems[J29]. The problem of sampling GACS signals is addressed in [J17] and the statistical function estimation is treated in [C35], [C37], [J25], [C42], [C43], [C44], [J27], [J30]. Statistical function estimation of SC signals is considered in [J18], [C40]. The problem of sampling is addressed in [J31]. A comprehensive treatment on GACS and SC processes is made in the the book [B1]. Surveys are presented in [J34] and [J37]. A third class of nonstationary signals that extends the class of the ACS signals is introduced in [J37]: the Oscillatory Almost-Cyclostationary (OACS) signals. These signals allow one to model the output of a generic linear time variant system when the input is an ACS signal.
Signal Analysis in the Nonstochastic Approach
Signal Processing for Wireless Systems