Demodulation of an OEO based vibration sensor with Hilbert Huang Transform

A demodulation method of an optoelectronic oscillator (OEO) based vibration sensor with Hilbert Huang Transform (HHT) is presented and demonstrated. The oscillation frequency of the OEO is modulated by the vibration induced dynamic strain on the sensor head and demodulated by the HHT method which works by decomposing the original signal into a series of intrinsic mode functions and then analyzing their Hilbert spectra. It is experimentally demonstrated that the vibration signals can be demodulated successfully with good accuracy, wide frequency response and fast speed certifying the feasibility of the method.