Time-frequency-phase tracking approach : Application to underwater signals in a passive context

Abstract

One of the most challenging applications of time-frequency representations deals with the analysis of the signal issued from natural environment. Recently, the interest for passive underwater context increased, basically due to the richness of the information carried out by the natural signals. Taken into account the non-linear multi-component time-frequency behavior of such signals, their analysis is a complex problem. In this paper we introduce a new time-frequency analysis concept that aims to extract the non-linear timefrequency components. The main feature of this technique is the joint use of time-amplitude, time-frequency and timephase information. This is materialized by a short-time polynomial phase modeling and the fusion of local information according to the best locally matches of local cubic frequency modulations. Tests provided on real data illustrate the benefits of the proposed approach.

Model-based parameters estimation of non-stationary signals using time warping and a measure of spectral concentration

“…This tracking method simultaneously finds the harmonics in a given window and can be applied in extraction and classification of time-frequency contours [24]. However, the procedure is limited to signals composed from a fundamental component and a number of harmonics in comparison to other multi-component time-frequency tracking approaches [4,25].…”

Source localization on solids utilizing time-frequency analysis of parameterized warped signals

“…This dispersive behavior of (3) results in a non-linear variation in phase of (2) with respect to ω. Any dispersive linear time-varying systems can be characterized by the non-linear phase function of the signal with respect to time [17] [18]. These non-linear functions are specific to the nature of the channel through which the signal propagates.…”

Time-frequency tracking using multi-window local phase analysis

“…For each window, the 2 nd order Warped HAF (High Order Ambiguity Function) is applied, providing 2 nd order phase modelling of one component [3]. The WHAF of order 2 is defined as the integral of the HAF,…”

“…Recently, a time-frequency tracking methodology has been developed [3], exploiting the coherence of the fundamental parameters of a signal, namely the instantaneous amplitude, frequency and phase. Specifically, the time-frequency components are analyzed by local phase analysis, using polynomial phase modeling.…”