Abstract: Safety power disconnection for remote power distribution in power distribution systems is disclosed. The power distribution system includes one or more power distribution circuits each configured to remotely distribute power from a power source over current carrying power conductors to remote units to provide power for remote unit operations. A remote unit is configured to decouple power from the power conductors thereby disconnecting the load of the remote unit from the power distribution system. A current measurement circuit in the power distribution system measures current flowing on the power conductors and provides a current measurement to the controller circuit. The controller circuit is configured to disconnect the power source from the power conductors for safety reasons in response to detecting a current from the power source in excess of a threshold current level indicating a load.

Abstract: The receiver including a package, first and second optical fibers, a capillary, and an array lens is disclosed. The first fiber has a first edge coupling to a MMI device by propagating a signal beam. The second fiber has a second edge coupling to the MMI device by propagating a local beam. The array lens has first and second lenses. The first lens converts the signal beam into a collimating beam, and the second lens converts the local beam into a collimating beam. The capillary has an edge opposite to the array lens, and the edge has a first region including the first edge and a second region including the second edge. The first edge is slanted to a first axis, and the second edge is slanted to a second axis, and a direction of the first edge and a direction of the second edge are different each other.

Abstract: An all-optical network comprises: a first network; a second network; and a PWXC coupling the first network to the second network and comprising passive optical components. A method comprises: receiving a first optical signal from a first tail node of a first network; directing the first optical signal from a first input port of a PWXC to a first output port of the PWXC using first passive optical components; and transmitting the first optical signal to a third head node of a third network. An all-optical network comprising: a light bank; a first network coupled to the light bank; a second network coupled to the light bank; and a first PWXC coupling the first network and the second network.

Abstract: Test equipment that is able to concurrently evaluate two or more optical modules each processing a wavelength multiplexed signal that multiplexes optical signals attributed to wavelengths different from each other. The test equipment provides a first test station and a second test station. After selecting one of the wavelengths, the first test station performs a first evaluation for an optical signal attributed to the one of the wavelengths and coming from the first optical module, and the second station concurrently performs a second evaluation for an optical single with the one of the wavelengths and coming from the second optical module. Thereafter, the first test station performs the first evaluation for the optical signal coming from the second optical module, while, the second test station performs the second evaluation for the optical signal coming from the first optical module.

Abstract: Described examples provide for digital communication circuits and systems that implement digital pre-distortion (DPD). In an example, a circuit includes a baseband DPD circuit, up-conversion circuitry, and feedback circuitry. The baseband DPD circuit comprises a baseband signal path and pre-distortion path. The pre-distortion path is configured to generate a pre-distortion signal based on the baseband signal. The baseband DPD circuit includes a first adder configured to add the baseband signal from the baseband signal path and the pre-distortion signal from the pre-distortion path to generate a pre-distorted baseband signal. The up-conversion circuitry is configured to convert the pre-distorted baseband signal to a radio frequency signal. The up-conversion circuitry is configured to be coupled to an input of a cable television (CATV) amplifier.

Abstract: Disclosed herein are techniques, methods, structures and apparatus that provide a silicon photonics multicarrier optical transceiver wherein both the transmitter and receiver are integrated on a single silicon chip and which generates a plurality of carriers through the effect of an on-chip modulator, amplifies the optical power of the carriers through the effect of an off-chip amplifier, and generates M orthogonal sets of carriers through the effect of an on-chip basis former.

Abstract: Methods and systems for a polarization immune wavelength division multiplexing demultiplexer are disclosed and may include, in an optoelectronic transceiver having an input coupler, a demultiplexer, and an amplitude scrambler: receiving input optical signals via the input coupler, communicating the input optical signals to the amplitude scrambler via waveguides, configuring the average optical power in each of the waveguides utilizing the amplitude scrambler, and demultiplexing the optical signals utilizing the demultiplexer. The amplitude scrambler may include phase modulators and a coupling section. The phase modulators may include sections of P-N junctions in the two waveguides. The demultiplexer may include a Mach-Zehnder Interferometer. The demultiplexed signals may be received utilizing photodetectors. The input coupler may include a polarization splitting grating coupler.

Abstract: To enable the transmission and reception of a super-channel optical signal to continue maintaining the possible transmission capacity without providing a redundant configuration in advance even though a failure occurs in a subcarrier, an optical transmitter 10 of the present invention includes a splitting means 20 for splitting an inputted client signal so as to make frequency efficiency in optical modulation means optimized; optical modulation means 31 to 3N for modulating one of subcarriers having mutually different wavelengths with the client signal output; a multiplexing means 40 for multiplexing the modulated signals and outputting a super-channel optical signal; and a control means 50, in a state where a failure occurs in one of the subcarriers, for making a split client signal output to modulation means corresponding to a subcarrier having no failure and applying a modulation method with a higher frequency efficiency to at least one of the modulation means.

Abstract: In an optical receiver, a control unit determines an SOA current set value such that an SOA current becomes a maximum value ISOA_MAXwhen a VOA voltage is smaller than a first threshold value VVOA_LOW, determines the SOA current set value such that the SOA current becomes smaller than the maximum value ISOA_MAX and larger than a minimum value ISOA_MIN when the VOA voltage is equal to or larger than the first threshold value VVOA_LOW and is smaller than a second threshold value VVOA_HIGH, and determines the SOA current set value such that the SOA current is fixed to the minimum value ISOA_MIN when the VOA voltage is equal to or larger than the second threshold value VVOA_HIGH.

Abstract: An omnidirectional optical communication system. The omnidirectional optical communication system includes a multifaceted structure, a laser transmitter with a steerable mechanism, an optical detector receiver, and an angle-of-arrival system. In one aspect, the laser transmitter with a steerable mechanism, the optical detector receiver, and the angle-of-arrival system are housed in within the multifaceted structure, which enables omnidirectional optical communication. In another aspect, the omnidirectional optical communication system is used in a spacecraft for inter-spacecraft omnidirectional optical communication. In yet another aspect, the omnidirectional optical communication system is used in terrestrial applications for gigabit communications in WiFi, inter smartphones, internet of things and smart cities. In yet another aspect, the omnidirectional optical communication system further includes a global positioning system.

Abstract: An aircraft system comprises a first and second transceiver each configured to transmit and receive radio signals in respective first millimeter wave (mmW) frequency band and second mmW frequency band; and a processing unit configured to provide the data signals to the first and second transceivers for transmission and to receive demodulated signals from the first and second transceivers. The processing unit is further configured to output signals to alter the orientation of the first antenna to establish a first point-to-point connection with a first aircraft and to output signals to alter the orientation of the second antenna to establish a second point-to-point connection with a second aircraft; the first point-to-point connection and the second point-to-point connection forming part of a point-to-point aircraft relay ring network communicatively coupling a plurality of aircraft in a shared flight route area to each other.

Abstract: Embodiments of this application disclose a quantum signal detection method and a quantum signal detection apparatus. The method includes: splitting a received optical pulse sequence into a first pulse sequence and a second pulse sequence that are in orthogonal polarization, where the signal pulses are quantum signal pulses; obtaining information about the reference pulses; generating local oscillator light; splitting the local oscillator light into first local oscillator light and second local oscillator light whose intensities are the same and that are in orthogonal polarization; performing homodyne detection on the first pulse sequence and the first local oscillator light, and performing homodyne detection on the second pulse sequence and the second local oscillator light, to obtain homodyne detection results; and obtaining regular components of the signal pulses in the optical pulse sequence according to the homodyne detection results and the information about the reference pulses.

Abstract: A method for calibrating an OLTS includes calibrating a first optical power meter of the OLTS using a stabilized light source. The method further includes calibrating a second optical power meter of the OLTS using the stabilized light source. The method further includes setting a power of an internal light source using the calibrated first optical power meter. A calibration cable is connected to a first test port and a second test port during setting of the power level, and a connection of the calibration cord to the second test port is maintained between calibrating of the second optical power meter and setting of the power level.

Abstract: Embodiments of the present invention disclose an optical signal transmission method, apparatus, and system. The apparatus includes a short wavelength division multiplexer, a signal processor, a first linear driver, a second linear driver, a first transmitter, and a second transmitter. The signal processor is configured to perform bit rate allocation and code pattern modulation on a received binary signal, to obtain a first electrical signal to be sent to the first linear driver and a second electrical signal to be sent to the second linear driver. It can be learnt that, by implementing the embodiments of the present invention, a quantity of wavelengths transmitted in a multimode optical fiber can be reduced by performing bit rate allocation on a binary signal, thereby reducing interference between channels in the optical fiber for optical signal transmission.

Abstract: A method and apparatus for adjusting a modulation index of an analog optical signal using an interference phenomenon of a coherent light, the method including dividing an analog optical signal for a first path and a second path, extracting an optical carrier from an analog optical signal divided for the first path, controlling an intensity and a phase of the optical carrier, and controlling a modulation index of the analog optical signal by combining an analog optical signal divided for the second path and the optical carrier of which the intensity and the phase are controlled.

Abstract: Methods and systems for waveguide delay based equalization with current and optical summing in optical communication are disclosed and may include an optoelectronic receiver including a directional coupler, two or more photodetectors, and one or more current mirrors. The optoelectronic receiver may be operable to: receive an input optical signal; split the input optical signal into first and second optical signals using the directional coupler; generate a first electrical from the first optical signal using a first photodetector; generate a second electrical signal from the second optical signal using a second photodetector; mirror the second electrical signal using the current mirror; and sum the first electrical signal with the amplified second electrical signal. The optoelectronic receiver may be operable to delay the first optical signal before generating the first electrical signal, using a waveguide delay.

Abstract: In order to provide a feature with which it is possible to suppress the occurrence of an optical surge independently of the type of optical switch, there is provided an optical control device for processing inputted first light and outputting second light, wherein the optical control device is provided with: a switching unit for switching and outputting first light that has undergone a selected process; and a variable output unit connected in series to the switching unit, the variable output unit operating so as to reduce the optical power of the second light before switching by the switching unit is executed and to gradually increase the optical power of the second light after the switching is executed.

Abstract: The present disclosure relates to a method for testing a fiber optic network including a fiber distribution hub. The method includes providing a test splitter within the fiber distribution hub to provide optical connectivity between an F1 fiber and at least a portion of an F2 fiber network. The method also includes testing sending a test signal from the F1 fiber through the test splitter to the F2 fiber network, and replacing the test splitter after testing has been completed.

Abstract: A free-space optical signal receiver includes a plurality of detectors whose individual outputs are delayed to correct for variations in arrival time caused by aberration in the medium through which the optical signal propagates, and combined to provide a single output. Each of the plurality of detectors sense the free-space modulated optical signal and provide a detector signal representative of the modulation of the optical signal. Each detector signal is delayed by a delay value to generate a delayed signal, and each delay value is selected to correct for variation in arrival time of the optical signal at each of the detectors, resulting in the delayed signals being substantially time-aligned. The delayed signals are constructively combined into a combined signal representative of the modulation aspect, and the combined signal is provided as an output.

Abstract: A communication system includes three or more nodes and a multi-core fiber having a plurality of cores, the multi-core fiber being used in at least a partial segment of the connection between the nodes is provided. One node of the nodes is connected to the multi-core fiber and includes a connector configured to add and drop a signal to and from an allocated core exclusively allocated from among the cores as a communication path between the one node and another node of the nodes and/or configured to relay a signal transmitted through another core of the cores allocated for communication between other nodes in the multi-core fiber connected to the one node, and a relative positional relationship between a connection position of the allocated core in which a signal is added or dropped in the connector and a connection position of another core in which a signal is relayed in the connector is the same for all of the nodes connected to the multi-core fiber.