A microwave coherent detection system is presented which can be used to simultaneously measure the temperature and strain distribution along a fiber with high accuracy based on spontaneous Brillouin scattering. The system measures the Brillouin scattering and Rayleigh scattering in fiber simultaneously, using the ratio of the Rayleigh and spontaneous Brillouin backscattered light called Landau-Placzek Ratio (LPR), and scans the Brillouin spectrum to obtain the desired information. The measurement system setup is showed in this paper, and the system performances such as the spatial resolution, the spectrum, the measurement accuracy, the dynamic range, and the measurement time are analyzed. The analysis shows that the system can achieve the spatial resolution of 2m, temperature resolution of 1  and strain resolution of 20με.

Date Published: 20 May 2009
PDF: 7 pages
Proc. SPIE 7283, 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, 72830T (20 May 2009); doi: 10.1117/12.828617

Published in SPIE Proceedings Vol. 7283:
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment
Yudong Zhang; James C. Wyant; Robert A. Smythe; Hexin Wang, Editor(s)