By use of window functions, time-frequency analysis tools like Short Time Fourier Transform overcome a shortcoming of the Fourier Transform and enable us to study the timefrequency characteristics of signals which exhibit transient oscillatory behavior. Since the resulting representations depend on the choice of the window functions, it is important to know how they influence the analyses. One ...

As the useful time-frequency tool, the Fractional Fourier Transform (FRFT) and the Short Time Fourier Transform (STFT) have a great development of signal recognition. And the Reduced Fractional Fourier Transform (RFRFT) was recently proposed and has been used in the recognition and estimation of chirp signals. A new method based on STFT and RFRFT is presented for radar signals modulation recogn...

The continuous fractional Fourier transform (FRFT) performs a spectrum rotation of signal in the time–frequency plane, and it becomes an important tool for time-varying signal analysis. A discrete fractional Fourier transform has been recently developed by Santhanam and McClellan, but its results do not match those of the corresponding continuous fractional Fourier transforms. In this paper, we...

Fault detection in microgrids presents a strong technical challenge due to the dynamic operating conditions. Changing power generation and load impacts current magnitude direction, which has an adverse effect on microgrid protection scheme. To address this problem, paper addresses field-transform-based fault method immune The faults are simulated via Matlab/Simulink model of grid-connected phot...

In this paper we investigate how the short-time Fourier transform can be extended in a Clifford setting. We prove some of main properties such as orthogonality relation, reconstruction property and reproducing kernel formula. Moreover, show effects modulating translating signal window function, respectively. Finally, demonstrate Lieb’s uncertainty principle for transform.

A 3D windowed Fourier transform is proposed for fringe sequence analysis, which processes the joint spatial and temporal information of the fringe sequence simultaneously. The 2D windowed Fourier transform in the spatial domain and the 1D windowed Fourier transform in the temporal domain are two special cases of the proposed method. The principles of windowed Fourier filtering and windowed Four...

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 windowed Fourier transform (short time Fourier transform) and the S-transform are widely used signal processing tools for extracting frequency information from non-stationary signals. Previously, the windowed Fourier transform had been adopted for signals on graphs and has been shown to be very useful for extracting vertex-frequency information from graphs. However, high computational compl...