Abstract A time–frequency transform is a sesquilinear mapping from suitable family of test functions to on the plane. The goal quantify energy present in signal at any given time and frequency. further specified by imposing conditions such as those stemming basic transformations signals which an density should satisfy. We systematic study how properties are reflected associated evaluation origi...

Recently, a Monte Carlo approach was proposed for processing highly redundant continuous frames. In this paper, we present and analyze applications of new theory. The computational complexity the method relies on frame being so-called linear volume discretizable (LVD). LVD property means that number samples in coefficient space required by is proportional to resolution discrete signal. We show ...

The Wigner distribution (WD) is perhaps the most prominent quadratic time–frequency signal representation. In this paper, which has mainly tutorial character but also contains some new results, we describe extensions of the WD concept to multidimensional vector signals, nonstationary random processes, linear time-varying systems (deterministic and random), linear signal spaces, and frames. We d...

The joint time-frequency analysis (JTFA) is a signal processing technique in which signals are represented in both the time domain and the frequency domain simultaneously. Recently, this analysis technique has become an extremely powerful tool for analyzing nonstationary time series. One basic problem in business-cycle studies is how to deal with nonstationary time series. The market economy is...

We investigate the Weyl calculus of pseudodifferential operators with the methods of time-frequency analysis. As symbol classes we use the modulation spaces, which are the function spaces associated to the short-time Fourier transform and the Wigner distribution. We investigate the boundedness and Schatten-class properties of pseudodifferential operators, and furthermore we study their mapping ...

Most of signals in engineering are nonstationary and time-varying. The Fourier transform as a traditional approach can only provide the feature information in frequency domain. The time-frequency techniques may give a comprehensive description of signals in time-frequency planes. Based on some typical nonstationary signals, five time-frequency analysis methods, i.e., the short-time Fourier tran...

Abstract Space-time and time-varying metastructures have attracted a lot of research interest in recent years. On the other hand, digital programmable metasurfaces also gained great attention owing to their powerful capabilities controlling electromagnetic (EM) fields waves real time, which is very suitable for implementing spatiotemporal modulations manner. Accordingly, space-time-coding (STC)...