Abstract: A radio-frequency data transport infrastructure for transmitting radio-frequency data to and from equipment via optical fibers. Such data transport infrastructure being particularly suitable for equipping an aircraft.

Abstract: Apparatus for providing communication between ground-based User Equipment (UE) and at least one core network and a method for providing wireless communication between ground-based User Equipment (UE) and at least one core network are disclosed. The apparatus for providing communication between ground-based User Equipment (UE) and at least one core network comprises a plurality of low earth orbit satellites each comprising at least one satellite-based optical transmitter element and at least one satellite-based optical receiver element for providing at least one optical communication link; and at least one aerial vehicle comprising at least one aerial vehicle based optical transmitter element and at least one aerial vehicle based optical receiver element for providing at least one optical communication link and at least one directional antenna for providing a wireless communication link to a ground-based station and/or mobile UE.

Abstract: An OLT includes an NNI-PHY, a transmission reception unit that transmits a frame transmitted by an ONU, a control unit that transmits the frame if the transmission reception unit received the frame and the frame is not damaged, a process execution unit that executes a process of transmitting the frame to the NNI-PHY if the frame is the specific frame, and a monitoring judgment unit that executes at least one of a process of judging that the frame was discarded in the control unit if the frame does not pass between the control unit and the process execution unit within a first time and a process of judging that the frame was discarded in the process execution unit if the frame does not pass between the process execution unit and the NNI-PHY within a second time.

Abstract: A method and system for identifying entangled photons includes generating a plurality of sets of four entangled photons, wherein one pair of photons of each set are time correlated, thereby indicating that another pair of four entangled photons are entangled. A coincidence of one pair of photons of the plurality of the sets of four entangled photons is determined and an ordered list of coincidences is generated. A state value of at least one other photon of the other pair of the portion of the plurality of the sets of four entangled photons is determined and an ordered list of state values based on the determined state values is generated. The ordered list of coincidences is compared to the ordered list of state values to determine entangled state information including determined state values that correspond to entangled sets of four entangled photons.

Abstract: An apparatus includes a photonic integrated circuit having an optical phased array, where the optical phased array includes multiple unit cells. Each unit cell includes (i) an antenna element configured to transmit or receive optical signals and (ii) a phase modulator configured to modify phases of the optical signals being transmitted or received by the antenna element. The apparatus also includes a gyroscopic sensor configured to sense movement of the photonic integrated circuit, where at least a portion of the gyroscopic sensor is integrated within the photonic integrated circuit.

Abstract: Methods, systems, and devices for quantum key distribution (QKD) in passive optical networks (PONs) are described. A PON may be a point-to-multipoint system and may include a central node in communication with multiple remote nodes. In some cases, each remote node may include a QKD transmitter configured to generate a quantum pulse indicating a quantum key, a synchronization pulse generator configured to generate a timing indication of the quantum pulse, and filter configured to output the quantum pulse and the timing indication to the central node via an optical component (e.g., an optical splitter, a cyclic arrayed waveguide grating (AWG) router). The central node may receive the timing indications and quantum pulses from multiple remote nodes. Thus, the central node and remote nodes may be configured to communicate data encrypted using quantum keys.

Abstract: An optical transmission device includes: a control module generate a control signal output which includes a slope adjust signal and a bias voltage offset adjust signal according to an input signal indicating a dispersion amount an electrical level adjust signal; a multi-level pulse amplitude modulator; and an asymmetrical optical modulator which is controlled by the slope adjust signal to be operated at one of a positive slope and a negative slope of a transfer function of the asymmetrical optical modulator itself, and is controlled by the bias voltage offset adjust signal of the control signal output to offset a bias voltage point of the asymmetrical optical modulator itself from a quadrature point of the transfer function, and modulates the multi-level pulse amplitude modulation signal to an optical signal to generate an optical modulate signal having a chirp.

Abstract: The present disclosure provides a method. The method comprises: Step S1: configuring a periodic excitation source to transmit a periodic excitation signal A; Step S2: sampling an output signal A+NA at an output point of the periodic excitation signal A with a sampling device AA, and averaging the output signal A+NA over one or more periods to filter noise; Step S3: inputting the sampled output signal A+NA as in input to a device or a channel H to be measured; Step S4: sampling an output signal B+NB at an output point of the device or the channel H to be measured with a sampling device BB, and averaging the output signal B+NB over one or more periods to filter noise; and Step S5: transmitting sampling results from the sampling device AA and the sampling device BB to an analysis software C to calculate a transfer function of the device or the channel H to be measured.

Abstract: An apparatus for determining an interference in a transmission medium during a transmission of a data input signal according to an embodiment has a transform module configured to transform the data input signal from a time domain to a frequency domain comprising a plurality of frequency channels to obtain a frequency-domain data signal comprising a plurality of spectral coefficients, wherein each spectral coefficient is assigned to one of the frequency channels, an analysis module configured to determine the interference by determining one or more spectral interference coefficients, wherein each spectral interference coefficient is assigned to one frequency channel.

Abstract: A method and an apparatus for receiving quantum optical communication while reducing receiver, increasing maximum detection speed, or both. The disclosure comprises transforming the polarization encoded output of a QKD system to time-bin encoded output at the detector level. The disclosure also comprises a method and an apparatus using a quantum optical switch and several SPD units to increase communication speed.

Abstract: An optical communication system which is tunable and polarization insensitive is provided herein. The optical communication system may comprise an optical bench coupling an optical transmit pathway and an optical receiving pathway to an external pathway. The optical bench includes a polarization insensitive optical circulator. The system may further include a tunable component positioned along the optical receiving pathway, and a controller coupled to the tunable component.

Abstract: Devices, methods for analog-to-digital converters (ADCs) that perform high-dynamic range measurements based on optical techniques are disclosed. In one example aspect, an optical encoder includes a polarization rotator configured to receive a train of optical pulses, and an electro-optic (EO) modulator coupled to an output of the polarization rotator. The EO modulator is configured to receive a radio frequency (RF) signal and to produce a phase modulated signal in accordance with the RF signal. The optical encoder also includes a polarizing beam splitter coupled to the output of the EO modulator; and an optical hybrid configured to receive two optical signals from the polarizing beam splitter and to produce four optical outputs that are each phase shifted with respect to one another.

Abstract: Disclosed is a self-coherent receiver based on polarization-independent delay interferometers, relating to a technical field of optical communication, including a first beam splitter, a first circulator, a second circulator, a first polarization-independent delay interferometer, a second polarization-independent delay interferometer, a first balanced detector, a second balanced detector and an electrical signal processing module.

Abstract: An optical transceiver with a built-in heat transfer structure is described. The heat transfer structure can connect one or more circuit regions of the optical transceiver to a heat sink while bypassing circuit regions that may impede the transfer of heat from the one or more circuit regions. The heat transfer structure may directly contact the one or more circuit regions, and the heat sink and may include an opening to avoid contact with the circuit regions to be bypassed.

Abstract: The application discloses a polarization independent DQPSK demodulation integrated optical chip, which comprises a first beam splitter, a first polarization beam splitter rotator, a second beam splitter, a third beam splitter, a first quarter-wave plate, a first delayed optical waveguide, and a second polarization beam splitter rotator that are integrated on a same substrate.

Abstract: An optical transmitter includes an electro-optic modulator, a monitor circuit that monitors output light of the electro-optic modulator, and a processor that controls a bias voltage of the electro-optic modulator using a monitoring result of the monitor circuit, wherein the processor superimposes a first dither signal with a first frequency and a second dither signal with a second frequency different from the first frequency, onto one bias voltage in a time sharing manner, calculates a first control error based on a first component oscillating at the first frequency and a second control error based on a second component oscillating at the second frequency based on the monitoring result, and determines a control value for controlling the bias voltage using the first control error and the second control error.

Abstract: The systems and methods directed towards a reconfigurable optical add-drop multiplexer (ROADM). The ROADM comprising: i) a plurality of line cards, wherein each one of the plurality of line cards is configured to receive a plurality of wavelength channels from an optical link in an optical network; ii) a plurality of add/drop cards, wherein each one of the plurality of add/drop cards includes a primary path and a secondary path; and iii) a controller configured to: a) select a set of wavelength channels from the plurality of wavelength channels, b) determine if there is any contention between the set of wavelength channels, c) direct a first subset of wavelength channels from the set of wavelength channels that do not have contentions to the primary path, and d) direct a second subset of wavelength channels from the set of wavelength channels that have contentions to the secondary path.

Abstract: A fiber-optic communication apparatus includes an optical monitor that monitors a WDM signal in which optical signals of multiple channels are multiplexed, a processor that calculates a control value for controlling an optical power of the WDM signal, based on a power spectrum detected by the optical monitor, in a unit interval of frequency narrower than a channel bandwidth of the WDM signal, and an optical power adjusting mechanism that adjusts the optical power of the WDM signal in the unit interval of frequency based on the control value.

Abstract: An integrated receiver chip comprising: a first end and a second end; at least one optical input port disposed at the first end; a polarization manipulation device optically connected to one of the at least one optical input port, the polarization manipulation device being adapted to split an optical signal into a first and a second optical signals; a first and a second dispersion compensators each optically connected to the polarization manipulation device, the first and the second dispersion compensators each being adapted to selectively induce a dispersion on an optical signal propagating through the dispersion compensator; and a first and a second photodetectors optically connected to the first and the second dispersion compensators, respectively.

Abstract: Methods and systems for a distributed optical transmitter with local domain splitting are disclosed and may include, in an optical modulator integrated in a silicon photonics chip: receiving electrical signals, communicating the electrical signals to domain splitters along a length of waveguides of the optical modulator via one or more delay lines, and generating electrical signals in voltage domains utilizing the domain splitters for modulating the optical signals in the waveguides of the optical modulator by driving diodes with the electrical signals generated in the voltage domains. The delay lines may comprise one delay element per domain splitter, or may comprise a delay element per domain splitter for a first subset of the domain splitters and more than one delay element per domain splitter for a second subset of the domain splitters.