Abstract:
Brillouin fiber sensing using stimulated Brillouin scattering in fibers to measure temperature and stress with the features of high-spatial resolution, long sensing range, small measurement error, etc. Therefore, Brillouin fiber sensing becomes the hotspot in recent two or three decades. Through research and analysis on the progress of long range distributed Brillouin sensing, main limitations and key techniques are generalized in this paper. Long range sensing schemes based on time division multiplexing, frequency division multiplexing, pulse coding, wide-bandwidth frequency modulation and image processing methods are emphatically introduced here. With long range Brillouin sensors applied in practice, increasing demand for fast measurement emerges, which we believe will be dominant in the research of long range Brillouin fiber sensing in the future.