Techniques for transmitting an optical signal through optical fiber with an improved stimulated Brillouin scattering (SBS) suppression and an improved transmitter's signal to noise ratio (SNR) include externally modulating a light beam emitted from a light source with a high frequency signal. The light beam is also modulated externally with an RF information-carrying signal. The high frequency signal is at least twice a highest frequency of the RF signal. The high frequency signal modulating the light source can be split, providing a portion of the split signal to a phase and gain control circuit for adjusting a phase/gain. The output of phase and gain control circuit can be applied to the external modulator to eliminate intensity modulation for SBS suppression improvement. The optical transmitter's SNR is further improved by cancelling a beat between SBS suppression modulation tone and out of band distortion spectrum of information bearing RF signal.

The present invention is to provide a backscattered light amplification device, an optical pulse test apparatus, a backscattered light amplification method, and an optical pulse test method for amplifying a desired propagation mode of Rayleigh backscattered light with a desired gain by stimulated Brillouin scattering in a fiber under test having the plurality of propagation modes. The backscattered light amplification device according to the present invention is configured to control individually power, incident timing, and pulse width of a pump pulse for each propagation mode when the pump pulse is incident in a plurality of propagation modes after the probe pulse is input to the fiber under test in any propagation mode.

The present invention is to provide a backscattered light amplification device, an optical pulse test apparatus, a backscattered light amplification method, and an optical pulse test method for amplifying a desired propagation mode of Rayleigh backscattered light with a desired gain by stimulated Brillouin scattering in a fiber under test having the plurality of propagation modes. The backscattered light amplification device according to the present invention is configured to control individually power, incident timing, and pulse width of a pump pulse for each propagation mode when the pump pulse is incident in a plurality of propagation modes after the probe pulse is input to the fiber under test in any propagation mode.

A fiber optic sensing technology for vehicle run-off-road incident automatic detection by an indicator of sonic alert pattern (SNAP) vibration patterns. A machine learning method is employed and trained and evaluated against a variety of heterogeneous factors using controlled experiments, demonstrating applicability for future field deployment. Extracted events resulting from operation of our system may be advantageously incorporated into existing management systems for intelligent transportation and smart city applications, facilitating real-time alleviation of traffic congestion and/or providing a quick response rescue and clearance operation.

A fiber optic sensing technology for vehicle run-off-road incident automatic detection by an indicator of sonic alert pattern (SNAP) vibration patterns. A machine learning method is employed and trained and evaluated against a variety of heterogeneous factors using controlled experiments, demonstrating applicability for future field deployment. Extracted events resulting from operation of our system may be advantageously incorporated into existing management systems for intelligent transportation and smart city applications, facilitating real-time alleviation of traffic congestion and/or providing a quick response rescue and clearance operation.

Aspects of the present disclosure describe systems, methods. and structures in which guided acoustic Brillouin (GAWBS) noise is measured using a homodyne measurement technique and demonstrated using a number of optical fibers, such fibers being commonly used in contemporary optical communications systems. The measurements are made with single spans and determined to be consistent with separate multi-span long-distance measurements. Additionally, a technique for preparing an optical fiber exhibiting superior GAWBS noise characteristics by reducing coherence length of the optical fiber by spinning the fiber at a high rate during the drawing process such that birefringence coherence length is reduced.

Aspects of the present disclosure describe systems, methods. and structures in which guided acoustic Brillouin (GAWBS) noise is measured using a homodyne measurement technique and demonstrated using a number of optical fibers, such fibers being commonly used in contemporary optical communications systems. The measurements are made with single spans and determined to be consistent with separate multi-span long-distance measurements. Additionally, a technique for preparing an optical fiber exhibiting superior GAWBS noise characteristics by reducing coherence length of the optical fiber by spinning the fiber at a high rate during the drawing process such that birefringence coherence length is reduced.

A system for an aircraft that includes a plurality of zones including: a first fiber optic cable routed through a zone of the plurality of zones. The first fiber optic cable is attached to a landing gear of the aircraft in the zone of the plurality of zones; and a first controller configured to provide a first optical signal to the first fiber optic cable and obtain a first optical response signal from the first fiber optic cable. The first controller is further configured to determine at least one temperature within the zone of the plurality of zones based on the first optical response signal, the first optical signal, and coherent optical frequency domain reflectometry (COFDR).

A system for an aircraft that includes a plurality of zones including: a first fiber optic cable routed through a zone of the plurality of zones. The first fiber optic cable is attached to a landing gear of the aircraft in the zone of the plurality of zones; and a first controller configured to provide a first optical signal to the first fiber optic cable and obtain a first optical response signal from the first fiber optic cable. The first controller is further configured to determine at least one temperature within the zone of the plurality of zones based on the first optical response signal, the first optical signal, and coherent optical frequency domain reflectometry (COFDR).

The disclosed systems and methods support addition of bands to a multi-band optical interface. The systems and methods can include a multi-band interface device for optical networks. The device can include a multi-band optical amplifier, a C-Band Add/Drop multiplexer, an L-Band Add/Drop multiplexer and an amplifier noise source. The multi-band optical amplifier can be connected to the C-Band Add/Drop multiplexer and connected to the L-Band Add/Drop multiplexer through the amplifier noise source. The amplifier noise source be configured to generate a combination of bulk noise and an input transmission received from the L-Band Add/Drop multiplexer. The gain of the amplifier noise source can depend on the power of the received input transmission. The power of the received input transmission can be increased over a period of time, transitioning the amplifier noise source from acting as a bulk noise source to acting an amplifier.