A large family of signal processing techniques consist of Fourier-transforming a signal, manipulating the Fourier-transformed data in a simple way, and reversing the transformation. We widely use Fourier frequency analysis in equalization of audio recordings, X-ray crystallography, artefact removal in Neurological signal and image processing, Voice Activity Detection in Brain stem speech evoked...

The essence of GPS signal acquisition is a two-dimensional search process for the carrier Doppler and code phase, generally including correlator, signal capture device, and logic control module. The disposal efficiency of correlator would affect the capture speed of the whole acquisition process. Because of the corresponding relation between frequencydomain multiplication and time-domain convol...

The terms Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (IFFT) are used to denote efficient and fast algorithms to compute the Discrete Fourier Transform (DFT) and the Inverse Discrete Fourier Transform (IDFT) respectively. The FFT/IFFT is widely used in many digital signal processing applications and the efficient implementation of the FFT/IFFT is a topic of continuous research.

The FFT is used widely in signal processing for efficient computation of the Fourier transform (FT) over a set of uniformly spaced frequency locations. However, in many applications, one requires nonuniform sampling in the frequency domain, i.e., a nonuniform FT. Several papers have described fast approximations for the nonuniform FT based on interpolating an oversampled FFT. This paper present...

Based on the software platform of MATLAB simula-tion, the paper collects the real GPS intermediate frequency (IF) signal by the IF signal sampler, and uses it to carry out the time-domain correlation acquisition and the fast Fourier transform (FFT) acquisition on the C/A code of GPS signal, and also carry out the decision of the singlebinary search and the M/N search on the personal computer. T...

In this paper, we present a new fast Fourier transform (FFT) algorithm to reduce the table size of twiddle factors required in pipelined FFT processing. The table size is large enough to occupy significant area and power consumption in long-point FFT processing. The proposed algorithm can reduce the table size to half, compared to the radix-22 algorithm, while retaining the simple structure. To...

Differences between spectral estimation techniques using fast Fourier transform (FFT), autoregressive modelling (AR) and Lomp-Scargle periodogram (LSP) with respect to the impact of metronomic breathing on sympathovagal balance were investigated by calculating heart rate variability frequency domain LF/HF ratio for 25 subjects under paced respiration. All techniques showed a significant increas...

The fast Fourier transform (FFT), developed in 1965, is widely considered one of the most prolific and significant algorithms of the 20th century. While the classic Fourier Transform algorithm converts data from timedomain to frequency domain in O(N), the FFT reduces the complexity to O(NlgN). This performance improvement has had a significant impact on many fields and has revolutionized the ar...

In digital signal processing, the Fast Fourier Transform (FFT) is a kind of high efficient method to calculate the discrete Fourier transform (DFT). It cuts the discrete signal sequence which the length is N for different radix sequences to operate using the way of handing back and partition. Currently, the radix-2 FFT algorithm is a popular approach to do the transform work. However, its compu...

1. ABSTRACT In a recent publication, we reported on the utilization of a LabVIEW based Communication Systems Toolkit in the investigation of a novel idea for envelope detection of amplitude modulated (AM) signals (Wright, Tanyel 2005). In this paper, we will describe our efforts to develop the toolkit further and our investigations into the Walsh domain with the help of our latest developments....