Sequential Fourier transform and its application

Abstract

Fourier transform is an essential procedure to obtain vibration characteristics of structure. Fast Fourier Transform (FFT) Algorithm is often used to calculate Fourier spectrum. However, if FFT algorithm is used for a real-time continuous monitoring of Fourier spectrum, calculation for every new sample occurs a waste of computational resources. Sequential Fourier Transform is basically based on discrete Fourier transform by storing of samples in ring buffer. Difference of Fourier spectrum is calculated on every single sample updating. Therefore, the number of multiplications on the single sample updating are minimized compared with FFT. This paper describes outline of Sequential Fourier Transform technique, cumulative Fourier spectrum, real time filtering and examples of implementation.