Non-uniform discrete Fourier transform

About: Non-uniform discrete Fourier transform is a research topic. Over the lifetime, 4067 publications have been published within this topic receiving 123952 citations.

Advanced methods of spectral analysis of quasiperiodic wave-like processes in the ionosphere: Specific features and experimental results

Abstract: Backgrounds of adaptive Fourier transform and analytical wavelet transform have been briefly described in comparison with traditional Fourier transform using a time window. As an example, all three transforms are used to analyze quasiperiodic wave-like processes in the ionosphere, which accompanied the passage of the solar terminator and rocket launch from the Plesetsk site. The advantages of adaptive Fourier transform and analytical wavelet transform as compared to traditional Fourier transform, which make it possible to reliably detect wave-like disturbances against a background of noise at a signal-to-noise ratio not less than 0.1, have been demonstrated.

A comment on the computational complexity of sliding FFT

Abstract: The sliding fast Fourier transform (FFT) is reviewed and is shown to have the computational complexity of N complex multiplications per sample, as opposed to the well-cited assumption of (N/2) log/sub 2/ N complex multiplication per sample reported in a book by L.R. Rabiner and B. Gold (1975). >

Computing the Waiting Time Distribution for the G/G/1 Queue by Signal Processing Methods

Abstract: Two methods, based on signal processing techniques, are presented for obtaining numerical solutions for the general single server queue with first-come, first-served discipline The first method is based on the use of the fast Fourier transform (FFT) for producing iterative solutions to a discrete version of Lindley's integral equation for both nonsteady state and equilibrium conditions The second method makes use of the complex cepstrum, implemented with the FFT, for providing direct solutions with the queue in equilibrium

Transform coding apparatus

Abstract: This invention relates to a transform coding apparatus where linear transform is performed for input signal series such as image signals, and transform coefficients are quantized from lower frequency compo-nents to higher frequency components in the transform region, and then the quantized transform coefficients are coded and outputted. The quantized transform coefficients being zero are counted, and when the count value exceeds the prescribed threshold value, the quantization is terminated so that high speed in the coding is intended and variation of the code generation rate can be prevented.