Reflectometric Measurement of Temperature Using a Single-Mode–Multimode–Single-Mode Fiber-Optic Structure

The possibility of using a single-mode–multimode–single-mode fiber-optic structure for remote measurement of temperature by an optical reflectometer is established. Experiments on measuring temperature using a structure with a multimode-fiber length of 10 mm in the temperature range of 30–70°C at wavelengths of 1310 and 1550 nm have been performed. The total length of the single-mode fiber line for reflectometric measurements was 20 km.