This paper proposes two new approaches for formant tracking using Fourier and wavelet ridges. The speech signal is decomposed into Time-Frequency representations issued from windowed Fourier transform and wavelet transform. Formant tracking is achieved by exploring ridges from time-frequency representation and imposing continuity constraints on formant trajectories. These approaches are validat...

Aimed at solving the problems of Precision code’s complex acquisition procedures and its long acquisition time in satellite navigation, this paper makes an architecture analysis of the commonly used direct acquisition algorithms of Precision code, making an improvement of the common local pseudorandom code based glide Fast Fourier Transform acquisition architecture. Besides those, it also puts ...

The problem of detecting transient signals in a noisy environment has been studied for decades. In the Statistical Signal Detection Theory the presence of a useful signal in a background noise is normally cast as a hypothesis testing, where under the null hypothesis no signal is present. If the statistics of signal to be detected is not perfectly known, usually no uniformly most powerful (UMP) ...

A new signal-adaptive joint time-frequency distribution for the analysis of nonstationary signals is proposed. It is based on a fractionalFourier-domain realization of the weighted Wigner distribution producing auto-terms close to the ones in the Wigner distribution itself, but with reduced cross-terms. Improvement over the standard time-frequency representations is achieved when the principal ...

AMS Subject Classi cation: 20-04, 05C25, 20C30 Rockmore was supported in part by a National Science Foundation Mathematical Sciences Postdoctoral Fellowship. We study the complexity of performing Fourier analysis for the group SL2(Fq), where Fq is the finite field of q elements. Direct computation of a complete set of Fourier transforms for a complex-valued function f on SL2(Fq) requires q6 ope...

It seems likely that improvements in arithmetic speed will continue to outpace advances in communications bandwidth. Furthermore, as more and more problems are working on huge datasets, it is becoming increasingly likely that data will be distributed across many processors because one processor does not have sufficient storage capacity. For these reasons, we propose that an inexact DFT such as ...

The Short Term Fourier Transform (STFT) is a classical linear time-frequency (T-F) representation. Despites its relative simplicity, it has become a standard tool for the analysis of non-stationary signals. Since it provides a redundant representation, it raises some issues such as (i) “optimal” window choice for analysis, (ii) existence and determination of an inverse transformation, (iii) per...