Abstract: Based on elliptic Fourier descriptors, vibration signals measured from the same section of the orbit by a couple of sensor mounted in radial direction 90º apart are analyzed in data fusion. The theoretical expression of filtered orbit is derived. The full spectrum, the holospectrum, and the vector spectrum are compared, a general theoretical framework for these three kinds spectrum is proposed, and a numerical method to obtain these three kinds spectrum by one Fourier transform is designed. The vector ellipse spectrum which is synthesized by the full spectrum, the holospectrum, and the vector spectrum is proposed as a new method to analyze synchronous vibration signals. The comparison shows that the vector ellipse spectrum is simple and feasible.

Key words: Elliptic Fourier descriptors, Full spectrum, Holospectrum, Rotating machinery, Vector spectrum