High-resolution Ofdr Key Technologies

OFDR is an advanced fiber measurement. It has a better space resolution than the OTDR. OFDR has broad application prospects in the fields of communication, medicine, sensor, etc. The key technologies of high resolution OFDR are studied theoretically and experimentally in this dissertation to design and construct the OFDR system.The following research works are focused on in this dissertation: The key technologies of OFDR are analyzed by studying the principle of OFDR; The system is designed by calculating and analyzing the parameter of the OFDR. The fiber laser and semiconductor laser are compared to choose a suitable laser; The influencing factors of linewidth of the fiber laser and the working conditions of single longitudinal mode are analyzed; The technologies about how to make linewidth more narrow and the principle of fiber laser are studied to set up narrow linewidth single longitudinal mode fiber laser; The output characteristics of the narrow linewidth single longitudinal mode fiber laser are measured and studied experimentally; The linewidth measurement system is set up to measure the linewidth of the fiber laser. The method of frequency chirp is designed by using the inverse piezoelectricity of piezoelectric; The frequency sweep of the laser is carried out and the output characteristics of frequency sweep are analyzed; The optical path is designed, and the OFDR system is set up finally.