In this paper, all-optical short-time Fourier transform (STFT) based on stimulated Brillouin scattering (SBS) is proposed and further used for real-time time-frequency analysis of different radio frequency (RF) signals. the STFT scheme, SBS not only provides a band-pass filter implementing window function in conjunction with periodic frequency-sweep optical signal but also obtains domain inform...

The fractional Fourier transform can be considered as a rotated standard Fourier transform in general and its benefit in signal processing is growing to be known more. Noise removing is one application that fractional Fourier transform can do well if the signal dilation is perfectly known. In this paper, we have computed the first and second order of moments of fractional Fourier transform acco...

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visual servoing is generally contained of control and feature tracking. study of previous methods shows that no attempt has been made to optimize these two parts together. in kernel based visual servoing method, the main objective is to combine and optimize these two parts together and to make an entire control loop. this main target is accomplished by using lyapanov theory. a lyapanov candidat...

introduction: an efficient method of tomographic imaging in nuclear medicine is positron emission tomography (pet). compared to spect, pet has the advantages of higher levels of sensitivity, spatial resolution and more accurate quantification. however, high noise levels in the image limit its diagnostic utility. noise removal in nuclear medicine is traditionally based on fourier decomposition o...

Development of robust and efficient front-end is crucial for robust ASR. Proper time and frequency resolution of the TFR of speech, motivated by the auditory models is considered an important factor for robustness. An efficient method of realizing a variable resolution TFR using DTFT/Goertzel algorithm is proposed instead of the standard FFT based approach. It is shown that the new representati...

In this paper, we examine the theory of motion-free superresolution by formulating the problem in the Discrete Time Fourier Transform (DTFT) and the Discrete Fourier Transform (DFT) domain. Our approach provides some new insights into how aliasing and blurring can effect exact reconstruction of the superresolved image. For ease of understanding, the analysis, is initially carried out in the 1-D...