Distributed Fiber Birefringence Measurement Using Pulse-Compression Φ-OTDR

Fiber Measurement Technique Based on OTDR

Influence of birefringence dispersion on spatial resolution of a distributed stress sensor using birefringence optical fiber

Distributed stress sensor with a scanning Michelson white light interferometer can be used to detect stress distribution and its value by analyzing polarization mode coupling caused by stress field in PMFs (polarization maintaining fibers). In the measurement of polarization coupling, the birefringence in sensing fiber is usually considered to be wavelength-independent. The spatial resolution o...

Distributed measurements of fiber birefringence and diametric load using optical low-coherence reflectometry and fiber gratings.

Polarization sensitive optical low-coherence reflectometry (OLCR) is used for measuring the complex fiber Bragg gratings (FBG) reflection coefficient. We determine the beat length directly from oscillations in the OLCR amplitude with a resolution of 10(-6) and a spatial resolution only limited by the minimum beat length or the coherence length of the light source. Using the OLCR amplitude and p...

Pulse compression using a tapered microstructure optical fiber.

We calculate the pulse compression in a tapered microstructure optical fiber with four layers of holes. We show that the primary limitation on pulse compression is the loss due to mode leakage. As a fiber's diameter decreases due to the tapering, so does the air-hole diameter, and at a sufficiently small diameter the guided mode loss becomes unacceptably high. For the four-layer geometry we con...

Extending the Radar Dynamic Range using Adaptive Pulse Compression

The matched filter in the radar receiver is only adapted to the transmitted signal version and its output will be wasted due to non-matching with the received signal from the environment. The sidelobes amplitude of the matched filter output in pulse compression radars are dependent on the transmitted coded waveforms that extended as much as the length of the code on both sides of the target loc...