Andrey Zhirnov

Experimental study of influence of nonlinear effects on phase- sensitive optical time-domain reflectometer operating range

This paper presents experimental results of a study the influence of nonlinear effects on the range of the phase-sensitive optical time-domain reflectometer. Results from measurements of the impact of the effects of stimulated Raman scattering, stimulated Brillouin scattering, self-phase modulation, and modulation instability are presented. It is shown that the power of the probe pulse for 200 ns does not exceed ≈300 mW.

Note: Gaussian mixture model for event recognition in optical time-domain reflectometry based sensing systems.

We propose a novel approach to the recognition of particular classes of non-conventional events in signals from phase-sensitive optical time-domain-reflectometry-based sensors. Our algorithmic solution has two main features: filtering aimed at the de-nosing of signals and a Gaussian mixture model to cluster them. We test the proposed algorithm using experimentally measured signals. The results show that two classes of events can be distinguished with the best-case recognition probability close to 0.9 at sufficient numbers of training samples.

Adaptation of the Er-Yb microchip laser for use in phase-sensitive optical time domain reflectometry

We report on the experiments related to the Er-Yb microchip laser setup with fiber diode pumping. The main goal is a new radiation source for the use in the phase-sensitive optical time domain reflectometry (φ-OTDR) development.

Er:Yb phosphate glass laser with nonlinear absorber for phase-sensitive optical time domain reflectometry

A novel laser for phase-sensitive optical time-domain reflectometry (Φ-OTDR) is presented. The advantages of a compact solid-state laser are listed, current problems are shown. Experiments with a microchip single-optical-element laser, from setup construction to usage in Φ-OTDR system, are presented. New laser scheme with two-photon intracavity absorber is suggested and its advantages are described.

Fiber-pumped Yb Er:glass microchip laser for coherent OTDR sensing

A single-frequency 1.5 um microchip erbium laser, diode-pumped through optical fiber, was developed and characterized with the aim of using it in coherent OTDR sensing applications. The laser is pumped by a fiber-coupled 976 nm laser diode and provides some 10 mW single-frequency output power at 1533.5 nm wavelength, suitable for sensing and measurements with optical fibers. Amplitude and phase noise of the 200 THz oscillator are under study for its use in specially designed OTDR measurements for remote sensing.