Abstract :
Fourier transform is a special integral transformation. The Fourier transform transforms the signal from the time domain to the frequency domain, and the frequency domain method has many outstanding advantages compared with the classical time domain method. Although Fourier analysis is not the only transform domain method in the field of information science and technology, it has to be recognized that Fourier transform analysis has always been widely used in this field. Fourier transform is used to realize the filtering, modulation and sampling of the signal, which is the most important application of Fourier transform in signal processing. Through the modulation of the signal can be low-frequency components of the signal modulation to high frequency, to achieve the spectrum shift, to reduce inter-code crosstalk, improve the new noise resistance, is conducive to long-distance transmission of the signal. In addition, the signal sampling can be continuous signal discretization, help to use the computer to deal with the signal. In short, Fourier transform has a very important role in signal processing, learning Fourier transform is the basis for learning other frequency domain transformations.
Keyword :
Fourier transform, time domain, frequency domain, signal processing, information science and technology, filtering, modulation, sampling