A Pluse Subdivision Superposition method for improving the spatial resolution in BOTDR system

In order to improve the spatial resolution of BOTDR system, a pulse subdivision superposition method is proposed. The real-time backscattering spectrum is regard as the superposition of all sub-backscattering spectrum within a given spatial resolution and environmental temperature. And the sub-backscattering spectrum is generated by the equivalent sub-pulse propagation in fiber. By analyzing the backscatter spectrum, the temperature information along the sensing optical fiber can be obtained. Theoretical and analytical results demonstrated that this method can improve the spatial resolution depending on the sampling rate and decrease the limitation of pulse width on the spatial resolution.