We study signal processing tasks in which the is mapped via some generalized time-frequency transform to a higher dimensional space, processed there, and synthesized an output signal. show how approximate such methods using quasi-Monte Carlo (QMC) approach. consider cases where representation redundant, having feature axes addition time frequency axes. The proposed QMC method allows sampling bo...

Abstract Due to the Heisenberg–Gabor uncertainty principle, finite oscillation transients are difficult localize simultaneously in both time and frequency. Classical estimators, like short-time Fourier transform or continuous-wavelet optimize either temporal frequency resolution, find a suboptimal tradeoff. Here, we introduce spectral estimator enabling time-frequency super-resolution, called s...

Mobile communication channels are often modeled as linear time-varying filters or, equivalently, as time-frequency integral operators with finite support in time and frequency. Such a characterization inherently assumes the signals are narrowband and may not be appropriate for wideband signals. In this paper time-scale characterizations are examined that are useful in wideband time-varying chan...