Methods and apparatus for a photonic acoustic-optic frequency shifter having an integrated layer of lithium niobate. An input port receives input light and an acoustic wave generator generates an acoustic wave into a deflection area comprising a layer of lithium niobate. A first output port exits undeflected light from the deflection area as transmitted light and a second output port exits light deflected in frequency by the acoustic wave in the deflection area.

The photonic integrated device comprises a substrate, a plurality of mechanical resonator structures on a surface of the substrate, exposed to receive sound waves from outside the device; a plurality of sensing optical waveguides, each sensing optical waveguide at least partly mechanically coupled to at least one of the mechanical resonator structures, or a sensing optical waveguide that is at least partly mechanically coupled to all of the mechanical resonator structures; an input optical waveguide on the surface of the substrate, coupled to the plurality of sensing optical waveguides or the single sensing optical waveguide, for supplying light to the plurality of sensing optical waveguides or the single sensing optical waveguide; at least one output optical waveguide on the surface of the substrate, coupled to the plurality of sensing optical waveguides or the single sensing optical waveguide, for collecting light from the plurality of sensing optical waveguides or the single sensing optical waveguide that has been affected by vibration of plurality of mechanical resonator structures.

The photonic integrated device comprises a substrate, a plurality of mechanical resonator structures on a surface of the substrate, exposed to receive sound waves from outside the device; a plurality of sensing optical waveguides, each sensing optical waveguide at least partly mechanically coupled to at least one of the mechanical resonator structures, or a sensing optical waveguide that is at least partly mechanically coupled to all of the mechanical resonator structures; an input optical waveguide on the surface of the substrate, coupled to the plurality of sensing optical waveguides or the single sensing optical waveguide, for supplying light to the plurality of sensing optical waveguides or the single sensing optical waveguide; at least one output optical waveguide on the surface of the substrate, coupled to the plurality of sensing optical waveguides or the single sensing optical waveguide, for collecting light from the plurality of sensing optical waveguides or the single sensing optical waveguide that has been affected by vibration of plurality of mechanical resonator structures.

Methods and apparatus for a photonic acoustic-optic frequency shifter having an integrated layer of lithium niobate. An input port receives input light and an acoustic wave generator generates an acoustic wave into a deflection area comprising a layer of lithium niobate. A first output port exits undeflected light from the deflection area as transmitted light and a second output port exits light deflected in frequency by the acoustic wave in the deflection area.

Methods and apparatus for a photonic acoustic-optic frequency shifter having an integrated layer of lithium niobate. An input port receives input light and an acoustic wave generator generates an acoustic wave into a deflection area comprising a layer of lithium niobate. A first output port exits undeflected light from the deflection area as transmitted light and a second output port exits light deflected in frequency by the acoustic wave in the deflection area.

A sensing system adapted to receive backscattered signal from a sensing fiber includes a first Faraday rotator mirror; a second Faraday rotator mirror; an optical hybrid coupled to the Faraday rotator mirrors, wherein one of the mirrors is coupled with an optical path difference; a 3-port optical circulator coupled to the sensing fiber and the optical hybrid; a first photodetector coupled to the circulator; and three photodetectors coupled to the optical hybrid.

A sensing system adapted to receive backscattered signal from a sensing fiber includes a first Faraday rotator mirror; a second Faraday rotator mirror; an optical hybrid coupled to the Faraday rotator mirrors, wherein one of the mirrors is coupled with an optical path difference; a 3-port optical circulator coupled to the sensing fiber and the optical hybrid; a first photodetector coupled to the circulator; and three photodetectors coupled to the optical hybrid.

A light source assembly having N outputs, the assembly including: a light source arrangement arranged for supplying light to M inputs, where M an N independently of each other are integers and where M≥2 and M≥N; at least one optical couplers, each having at least one input arm and a plurality of output arms; and an integer number, P, of mode scramblers. The light source arrangement may include a broadband light source and a multimode coupler configured for receiving one or more light beams from the light source arrangement, wherein the one or more light beams being derived from the broadband light source and wherein a mode scrambler is arranged for mode scrambling one of said light beams before it enters the multimode coupler.

A light source assembly having N outputs, the assembly including: a light source arrangement arranged for supplying light to M inputs, where M an N independently of each other are integers and where M≥2 and M≥N; at least one optical couplers, each having at least one input arm and a plurality of output arms; and an integer number, P, of mode scramblers. The light source arrangement may include a broadband light source and a multimode coupler configured for receiving one or more light beams from the light source arrangement, wherein the one or more light beams being derived from the broadband light source and wherein a mode scrambler is arranged for mode scrambling one of said light beams before it enters the multimode coupler.

A fiber optic sensor arrangement is disclosed that includes a plurality of optical fiber based sensor elements, the sensor elements configured to modify an associated optical carrier signal in accordance with changes in a sensed quantity at a location of the sensor element and a phase modulation arrangement for phase modulating each optical carrier signal in accordance with respective uncorrelated pseudorandom binary sequence signals. The sensor arrangement also includes an interferometer module for receiving each of the phase modulated optical carrier signals, the interferometer module operable to convert a change in the phase modulated optical carrier signals to a change in optical intensity of the corresponding optical carrier signal to generate a combined modulated optical intensity signal, an optical intensity detector for measuring the combined modulated optical intensity signal and generating a time varying electrical detector signal and an analog to digital convertor to convert the time varying electrical detector signal to a time varying digitized detector signal. Also included in the sensor arrangement is a decorrelator arrangement for decorrelating the time varying digitized detector signal against the respective uncorrelated pseudorandom binary sequence corresponding to each of the optical carrier signals to recover each of the modulated optical carrier signals and a demodulator for demodulating each of the modulated optical carrier signals to recover the respective optical carrier signal to determine the changes in the sensed quantity at the location of the sensor element.