Optical Time Domain Reflectometer System Research Articles

Rayleigh and Brillouin self-heterodyne detection Brillouin optical time domain reflectometer system based on phase shift keying pulse encoding

Rayleigh and Brillouin self-heterodyne detection Brillouin optical time domain reflectometer system based on phase shift keying pulse encoding

APD检测Golay编码BOTDR系统的建模分析与优化设计

APD检测Golay编码BOTDR系统的建模分析与优化设计

Resolution enhancement in long pulse OTDR for application in structural health monitoring

To improve the range resolution in inexpensive conventional long pulse optical time domain reflectometer (OTDR) for application in structural health monitoring (SHM) and robotic neural network, the Fourier Wavelet Regularized Deconvolution (ForWaRD) based on the adaptive wavelet method is employed. Since Deconvolution is a noise sensitive process, employing the (ForWaRD) method enhances the signal to noise ratio. Simulation for long pulse OTDR system is done and ForWaRD method is employed to improve the resolution of the OTDR system to the order of several centimeters. In this method the resolution is limited by the bandwidth of detector, bandwidth of electronic circuit, and the sampling rate of analog to digital convertor.

Quasi-distributed fibre-optic chemical sensing usingtelecom optical fibre

Quasi-distributed chemical sensing using telecommunications grade fibre is reported for the first time. Using graded index fibre, an etched cavity at each fibre tip is filled with sol-gel-derived-silica in which an analyte-sensitive reagent is entrapped. A standard optical time domain reflectometer system, interogating three such sensors based on a pH sensitive NIR absorbing dye was used to prove the principle of this approach.

Interferometric optical-time-domain reflectometer to determine backscattering characterization of silica-based glass waveguides

An interferometric optical-time-domain reflectometer (OTDR) system with high spatial resolution has been developed for diagnosis of optical waveguides and hybrid optical circuits. A spatial resolution as short as 14 μm is obtained by using a newly developed 1.3-μm-wavelength superluminescent diode, and a minimum detectable reflectivity of −100 dB is achieved. Scattering centers that are produced by waveguide irregularities are clearly observed in silica-based glass optical waveguides, and the loss origin of the waveguides is discussed. Also, evaluation of other waveguide characteristics, such as modal birefringence and facet reflectivity, can successfully be made by the OTDR system.

Real-time long range complementary correlation optical time domain reflectometer

The improved performance of an optical time-domain reflectometer (OTDR) through the application of a correlation technique using codes with complementary autocorrelation properties is discussed. The theoretical foundations of the method are presented along with experimental results exhibiting the best one-way range reported to date for a practical long-haul, long-wavelength OTDR system.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>