Lecture

Fast Fourier Transform (FFT): Lecture 4

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In course

PHYS-332: Computational physics III

This course teaches the students practical skills needed for solving modern physics problems by means of computation. A number of examples illustrate the utility of numerical computations in various domains of physics. ...

Description

This lecture covers the Fast Fourier Transform (FFT) algorithm, including the review of practical aspects of Discrete Fourier Transform (DFT), interpolation formula, FFT in N dimensions, and examples from exercise sessions. The FFT algorithm is explained as a divide and conquer approach, with details on radix-2 FFT and its implementation. The lecture also delves into the application of FFT in image processing, filters, noise removal, and experimental techniques like Transmission Electron Microscopy (TEM) and Scanning Tunneling Microscopy (STM).

Official source

Ontological neighbourhood

Information engineering

Signal processing: Fourier analysis, Filtering theory

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Low-pass filter

A low-pass filter is a filter that passes signals with a frequency lower than a selected cutoff frequency and attenuates signals with frequencies higher than the cutoff frequency. The exact frequency response of the filter depends on the filter design. The filter is sometimes called a high-cut filter, or treble-cut filter in audio applications. A low-pass filter is the complement of a high-pass filter. In optics, high-pass and low-pass may have different meanings, depending on whether referring to the frequency or wavelength of light, since these variables are inversely related.

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