A TASTE OF JAVA - DISCRETE AND FAST FOURIER TRANSFORMS

摘要

This paper attempts to present the development and application of a practical teaching module introducing Java programming techniques to electronics, computer and bioengineering students before they encounter digital signal processing and its applications in junior and/or senior level courses. The Fourier transform takes a signal in the time domain, switches it into the frequency domain, and vice versa. Fourier Transforms are extensively used in engineering and science in a wide variety of fields including acoustics, digital signal processing, image processing, geophysical processing, wavelet theory, optics and astronomy. The Discrete Fourier Transform (DFT) is an essential digital signal processing tool, and is highly desirable if the integral form of the Fourier Transform cannot be expressed as a mathematical equation. The key to spectral analysis is to choose a window length that suits the signal to be analyzed, since the length of window used for DFT calculations has a strong impact on the information the DFT can provide. The operation count of the DFT algorithm is time intensive, and as such a number of Fast Fourier Transform methods have been developed to perform DFT efficiently.