Physical Sciences and Mathematics Commons^™

The Fourier Spectrum Analysis Of Optical Feedback Self-Mixing Signal Under Weak And Moderate Feedback, Xiaojun Zhang, Jiangtao Xi, Yanguang Yu, Joe F. Chicharo

Professor Joe F. Chicharo

The spectrum characteristics of self-mixing signals observed in optical feedback self-mixing interferometry (OFSMI) is studied in this paper. The purpose is to provide guidance for the design of pre-processing techniques for eliminating noise or disturbance. The influence of two important parameters of the OFSMI system on the spectrum, that is, the optical feedback factor and the linewidth enhancment factor, are measured by means of Discrete Fourier transform (DFT). The simulated results show that, at a weak feedback, the OFSMI signals are strictly band limited in nature, with the cut-off frequencies being the vibration frequency and the fringe frequency respectively. Also …