Abstract: An optical routing element may include a planar dielectric photonic crystal which includes a lattice of holes having a first linear defect adjacent a second linear defect, with the two defects being separated by a central row of lattice holes. The first linear defect in the lattice of holes may form a first single mode line defect waveguide, and the second linear defect in the lattice of holes may form a second single mode line defect waveguide. Optical energy may be selectively coupled between the first and second waveguides across the central row of lattice holes. A free-carrier injector may be included to inject free-carriers into the dielectric photonic crystal, activation of which may alter selectivity of the optical coupling between the first and second waveguides. A plurality of optical routing elements with associated free-carrier injectors may be interconnected to form a bi-directional optical routing array.

Abstract: An optical routing element may include a planar dielectric photonic crystal which includes a lattice of holes having a first linear defect adjacent a second linear defect, with the two defects being separated by a central row of lattice holes. The first linear defect in the lattice of holes may form a first single mode line defect waveguide, and the second linear defect in the lattice of holes may form a second single mode line defect waveguide. Optical energy may be selectively coupled between the first and second waveguides across the central row of lattice holes. A free-carrier injector may be included to inject free-carriers into the dielectric photonic crystal, activation of which may alter selectivity of the optical coupling between the first and second waveguides. A plurality of optical routing elements with associated free-carrier injectors may be interconnected to form a bi-directional optical routing array.

Abstract: According to embodiments of the invention, the design and fabrication of a binary superimposed grating (BSG) results in better performing devices that may be fabricated using existing technology. The fabrication process includes forming grating features based upon repeating features of the desired superposition function. The design process also relaxes the processing requirement for equivalently performing devices.

Abstract: An optical feed network for a phased-array antenna may comprise a phase-based feed network that may include electro-optical phase shifting.

Abstract: An optical routing element may include a planar dielectric photonic crystal which includes a lattice of holes having a first linear defect adjacent a second linear defect, with the two defects being separated by a central row of lattice holes. The first linear defect in the lattice of holes may form a first single mode line defect waveguide, and the second linear defect in the lattice of holes may form a second single mode line defect waveguide. Optical energy may be selectively coupled between the first and second waveguides across the central row of lattice holes. A free-carrier injector may be included to inject free-carriers into the dielectric photonic crystal, activation of which may alter selectivity of the optical coupling between the first and second waveguides. A plurality of optical routing elements with associated free-carrier injectors may be interconnected to form a bi-directional optical routing array.

Abstract: An apparatus and method may be used to create images, e.g., three-dimensional images, based on received radio-frequency (RF), e.g., millimeter wave, signals carrying image data. The RF signals may be modulated onto optical carrier signals, and the resulting modulated optical signals may be cross-correlated. The resulting cross-correlations may be used to extract image data that may be used to generate three-dimensional images.

Abstract: An optical routing element may include a planar dielectric photonic crystal which includes a lattice of holes having a first linear defect adjacent a second linear defect, with the two defects being separated by a central row of lattice holes. The first linear defect in the lattice of holes may form a first single mode line defect waveguide, and the second linear defect in the lattice of holes may form a second single mode line defect waveguide. Optical energy may be selectively coupled between the first and second waveguides across the central row of lattice holes. A free-carrier injector may be included to inject free-carriers into the dielectric photonic crystal, activation of which may alter selectivity of the optical coupling between the first and second waveguides. A plurality of optical routing elements with associated free-carrier injectors may be interconnected to form a bi-directional optical routing array.

Abstract: A first image may be obtained using locked (relative) phases. A second image may be obtained using unlocked (e.g., randomized) phases. Data of the second image may be subtracted from data of the first image. The result may then undergo further processing, if desired, e.g., to further enhance the resulting image.

Abstract: An optical modulation apparatus for modulating an electromagnetic (e.g., radio frequency (RF)) signal onto an optical carrier signal may be arranged to feed back at least a portion of the optical carrier signal, while excluding first-order sidebands, which may help increase modulation efficiency and improve output power, while retaining high modulation bandwidth. Such arrangements may be implemented, for example, using a Fabry-Perot resonator or a ring resonator in combination with a Mach-Zehnder interferometer or a Michelson interferometer.

Abstract: An optical feed network for a phased-array antenna may comprise a phase-based feed network that may include electro-optical phase shifting.

Abstract: An optical modulation apparatus for modulating an electromagnetic (e.g., radio frequency (RF)) signal onto an optical carrier signal may use carrier recycling to increase modulation efficiency. Such an arrangement may be implemented, e.g., using a Fabry-Perot topology and/or using a travelling-wave modulator.

Abstract: An optical modulation apparatus for modulating an electromagnetic (e.g., radio frequency (RF)) signal onto an optical carrier signal may be arranged to feed back at least a portion of the optical carrier signal, while excluding first-order sidebands, which may help increase modulation efficiency and improve output power, while retaining high modulation bandwidth. Such arrangements may be implemented, for example, using a Fabry-Perot resonator or a ring resonator in combination with a Mach-Zehnder interferometer or a Michelson interferometer.

Abstract: Signal generating systems and methods are described. One signal generation system includes first and second lasers configured to generate first and second laser beams having respective frequencies wherein a difference in the respective frequencies corresponds to an output frequency, a photodetector configured to produce a signal at the output frequency, and first and second electro-optic modulators configured to respectively electro-optically modulate the first and second laser beams using the signal to produce respective first and second modulated optical signals, each of the first and second modulated optical signals having a respective sideband corresponding to the frequency of the other one of the first and second laser beams. The first laser is seeded with the respective sideband of the second modulated optical signal and the second laser is seeded with the respective sideband of the first modulated optical signal to phase-lock the first and second laser beams to each other.

Abstract: A method and apparatus for regenerating a received radio frequency (RF) signal may mix the received RF signal with a first laser signal, and the result, or a filtered version thereof, may be used to injection-seed a second laser. The result may be mixed with the first laser signal, and the result may be detected to provide a regenerated version of the received RF signal.

Abstract: An apparatus and/or method may be used for distributed synchronization of oscillators at non-collocated stations by means of transmitting and receiving optical signals having frequencies related to a desired oscillator frequency.

Abstract: An apparatus and method may be used to create images, e.g., three-dimensional images, based on received radio-frequency (RP), e.g., millimeter wave, signals carrying image data. The RF signals may be modulated onto optical carrier signals, and the resulting modulated optical signals may be cross-correlated. The resulting cross-correlations may be used to extract image data that may be used to generate three-dimensional images.

Abstract: A lithium niobate-based electro-optic modulator may include a ridged optical waveguide structure and/or a thinned substrate.

Abstract: Signal generating systems and methods are described. One signal generation system includes first and second lasers configured to generate first and second laser beams having respective frequencies wherein a difference in the respective frequencies corresponds to an output frequency, a photodetector configured to produce a signal at the output frequency, and first and second electro-optic modulators configured to respectively electro-optically modulate the first and second laser beams using the signal to produce respective first and second modulated optical signals, each of the first and second modulated optical signals having a respective sideband corresponding to the frequency of the other one of the first and second laser beams. The first laser is seeded with the respective sideband of the second modulated optical signal and the second laser is seeded with the respective sideband of the first modulated optical signal to phase-lock the first and second laser beams to each other.

Abstract: A method for manufacturing a modulator device is provided. The method includes providing an at least partially completed modulator having a top and a bottom and a substrate; fixedly mounting the top of the modulator on a mechanical support; removing from the bottom of the modulator a portion of the substrate, thereby forming a groove in the substrate; and separating the modulator with the groove from the mechanical support; wherein the reduced thickness of the substrate in the area of the groove restricts the flow of energy leakage into the substrate.

Abstract: According to embodiments of the invention, the design and fabrication of a binary superimposed grating (BSG) results in better performing devices that may be fabricated using existing technology. The fabrication process includes forming grating features based upon repeating features of the desired superposition function. The design process also relaxes the processing requirement for equivalently performing devices.