Chang, "Signal-to-noise ratio enhancement based on empirical mode decomposition in phase-sensitive optical time domain reflectometry
systems," Sensors, vol.
• Optical Time Domain Reflectometry
(OTDR) based DTS systems
With 10 [micro]m spatial resolution, 500 m range, 125 dB sensitivity, and no dead zones, the OBR takes high resolution optical time domain reflectometry
to the next level.
The intrusion sensing technique using Rayleigh scattering in a single-mode optical fiber had the advantage of providing distance information; however, the sensitivity in optical time domain reflectometry
(OTDR) configuration  was not sufficient for underground burial application.
Therefore, based on optical fiber sensing principles, optical time domain reflectometry
(OTDR) [10-12], and using the spatial structure of the beam, a new optical fiber sensor for landslides monitoring, COFT, was invented.