Fractional Fourier Transform for Ultrasonic Chirplet Signal Decomposition

Fractional Fourier Transform for Ultrasonic Chirplet Signal Decomposition

A fractional fourier transform (FrFT) based chirplet signal decomposition (FrFT-CSD) algorithm is proposed to analyze ultrasonic signals for NDE applications. Particularly, this method is utilized to isolate dominant chirplet echoes for successive steps in signal decomposition and parameter estimation. FrFT rotates the signal with an optimal transform order. The search of optimal transform orde...

Sonar Signal Enhancement Using Fractional Fourier Transform

Fractional Fourier Transform Based OFDMA for Doubly Dispersive Channels

The performance of Orthogonal Frequency Division Multiple Access (OFDMA) system degrades significantly in doubly dispersive channels. This is due to the fact that exponential sub-carriers do not match the singular functions of this type of channels. To solve this problem, we develop a system whose sub-carriers are chirp functions. This is equivalent to exploiting Fractional Fourier Transform (F...

Implementation of Discrete Fractional Fourier Transform for Signal Compression

An efficient method for implementing closed form discrete fractional Fourier transform for the purpose of signal compression is presented. Implementation method is compared with that of existing closed form discrete fractional Fourier transform, with respect to computational complexity, variance of quantization error, signal to noise ratio and number of bits for the representation of coefficien...

Fractional Fourier Transform

Abstract The integral transform method based on joint application of a fractional generalization of the Fourier transform and the classical Laplace transform is applied for solving Cauchy-type problems for the time-space fractional diffusion-wave equations expressed in terms of the Caputo time-fractional derivative and the generalized Weyl space-fractional operator. The solutions, representing ...