Title :
A DFB fiber laser sensor system with ultra-high resolution and its noise analysis
Author :
Xiao, Hao ; Li, Fang ; He, Jun ; Liu, Yuliang
Author_Institution :
Optoelectric Syst. Lab., Chinese Acad. of Sci. (CAS), Beijing, China
Abstract :
We describe a distributed feedback fiber laser (DFB FL) sensor system with ultra-high resolution. The sensor is made by writing distributed feedback structures into a high gain active fiber, and the system employs an unbalanced Michelson interferometer to translate laser wavelength shifts induced by weak measurands into phase shifts. A digital phase generated carrier demodulation scheme is introduced to achieve ultra-high resolution interrogation. A detailed noise analysis of the system is presented, and it is shown that the system resolution is limited by the frequency noise of the DFB FL.
Keywords :
Michelson interferometers; demodulation; distributed feedback lasers; fibre lasers; fibre optic sensors; laser noise; DFB FL sensor system; digital phase generated carrier demodulation scheme; distributed feedback fiber laser sensor; frequency noise; high gain active fiber; laser wavelength shift; noise analysis; phase shifts; ultrahigh resolution interrogation; unbalanced Michelson interferometer; Distributed feedback devices; Fiber lasers; Gain measurement; Laser feedback; Laser noise; Optical fiber sensors; Phase measurement; Phase shifting interferometry; Sensor systems; Writing; DFB fiber laser sensor system; PGC; fiber sensor; interferometer; noise analysis;
Conference_Titel :
Optical Fiber Sensors Conference, 2008. APOS '08. 1st Asia-Pacific
Conference_Location :
Chengdu
Print_ISBN :
978-1-4244-2131-2
Electronic_ISBN :
978-1-4244-2132-9
DOI :
10.1109/APOS.2008.5226313