The Brillouin optical time domain reflectometry (BOTDR) system measures the distributed strain and temperature information along the optic fibre by detecting the Brillouin gain spectra (BGS) and finding the Brillouin frequency shift profiles. By introducing small gain stimulated Brillouin scattering (SBS). dynamic measurement using BOTDR can be realized. but the performance is limited... https://megavitamines.shop/product-category/digestive-health-and-fiber/