Abstract: The present disclosure is directed to systems and methods of providing the next generation of quantum enabled cyber security systems. Such systems include a quantum network of satellites that will provide global coverage. The quantum satellite network includes quantum subnetworks comprised of LEO satellites. Some of these LEO satellite-based quantum subnetworks are connected to a subnetwork of MEO satellites. The MEO satellite subnetworks may then be interconnected to the global network of GEO satellites. The LEO/MEO satellites may also be used to interconnect terrestrial quantum networks. Each quantum communication subnetwork may be based on the cluster state concept.

Abstract: Provided is a signal processor provided in a transceiver for transmitting and receiving a radio signal, and including a branch unit, a detection unit, a determination unit, and a power source controller. The branch unit branches a transmission signal and acquires a branch signal. The detection unit detects the branch signal and acquires a voltage value of the branch signal. The determination unit compares the voltage value of the branch signal with a threshold voltage previously stored in a storage unit and determines whether the voltage value of the branch signal is equal to or greater than the threshold voltage. The power source controller controls turning on and off of a power source for a reception signal amplifier of the transceiver according to a determination result determined by the determination unit.

Abstract: A method for implementing an out-of-band communication channel in a coherent optical access network includes steps (a)-(e). Step (a) includes separating a MAC-layer signal received from a media access control (MAC) layer into an initial communication-channel signal and an initial data-channel signal. Step (b) includes encoding, using a first signal-coding scheme within a transceiver of a coherent passive optical network (PON), the initial communication-channel signal into a communication-channel signal occupying a first frequency band. Step (c) includes encoding, using a second signal-coding scheme within the transceiver, the initial data-channel signal into a data-channel signal occupying a second frequency band not overlapping the first frequency band. Step (d) includes combining the communication-channel signal and the data-channel signal to yield an analog signal.

Abstract: Techniques are provided for identifying and monitoring connections in an optical system. A plurality of optical ports is configured to receive a plurality of optical links that couple with one or more remote optical devices. At least one light source generates identification (ID) signals. At least one optical element configured to direct the ID signals into transmission paths from the source optical device to the remote optical device/s over the plurality of optical links. The remote optical device/s include one or more optical elements that direct the ID signals through a set of WDM filters and returns the ID signals. At least one optical element directs returned ID signals to an optical channel monitor. At least one microprocessor configured to execute control instructions to generate the ID signals and process one or more outputs of the optical channel monitor in response to the returned ID signals to identify the plurality of optical links.

Abstract: In order to measure the signal quality of each of optical signals transmitted/received via a plurality of transmission lines, an optical communication system 1 is provided with a dummy light source 10 for outputting dummy light, a switching means 20 for outputting the dummy light to a first transmission line 40a, and a light-receiving means 30 for acquiring first signal quality from the dummy light received via the first transmission line 40a, the switching means 20 switching the output destination of the dummy light from the first transmission line 40a to a second transmission line 40b, and the light-receiving means 30 acquiring second signal quality from the dummy light received via the second transmission line 40b.

Abstract: A method for locating a field device having a wireless interface is provided, the method including the following steps: transmitting, from the field device, identification information including distance information and direction information; receiving, by an operator device, the identification information; and displaying, by the operator device, based on the identification information, a distance, and a direction of the field device with respect to the operator device.

Abstract: A coherent transceiver includes a modulator, a receiver, a filter, a splitter, a detector, and a controller. The modulator modulates a data on the basis of laser light and outputs transmission light. The receiver receives reception light with same wavelength as the transmission light from input multiplexed light, on the basis of the laser light. The filter is arranged on an input stage of the receiver and includes a first port that inputs the multiplexed light, a filter body that transmits the reception light from the multiplexed light, and a second port that outputs the transmitted reception light. The splitter splits the transmission light travelling from the modulator and inputs the splitted transmission light. The detector detects a level of the splitted transmission light input. The controller adjusts a passband of the filter on the basis of the detected level.

Abstract: This application provides a receiver optical sub-assembly, a bi-directional optical sub-assembly, and an optical network device to improve anti-electromagnetic crosstalk performance of the receiver optical sub-assembly. The receiver optical sub-assembly includes: a photodiode, a trans-impedance amplifier, and a first filter component. The photodiode is configured to convert an optical signal into an electrical signal, a positive electrode of the photodiode is connected to an input terminal of the trans-impedance amplifier, and a negative electrode of the photodiode is configured to connect to a power supply. The trans-impedance amplifier is configured to amplify the electrical signal output by the photodiode, a power terminal of the trans-impedance amplifier is configured to connect to a power supply, and a first ground terminal of the trans-impedance amplifier is configured to connect to an external ground.

Abstract: A wavelength multiplexing system is presented comprising at least one basic functional unit extending between input and output light ports. The basic functional unit comprises at least one multi-core fiber. The multi-core fiber comprises N cores configured for supporting transmission of N wavelength channels ?1, . . . , ?n, wherein each of said at least one multi-core fibers is configured to apply a predetermined encoding pattern to the wavelength channels enabling linear mixing between them while propagating through multiple cores of said multi-core fiber. The encoding pattern may be configured to affect light propagation paths in the cores by inducing a predetermined dispersion pattern causing linear interaction and mixing between the channels; or may be configured to affect spectral encoding of the channels being transmitted through the cores by applying different weights to the channels.

Abstract: A system can include an optical receiver. The optical receiver can have an optical delay component and at least one electrical component (e.g., diode, resistor and/or transistor) operatively coupled to (e.g., integrated within) the optical delay component. The system can further include a processing device, operatively coupled to a memory, that can tune an amount of optical delay implemented by the optical delay component in a low loss and/or low dispersion manner. For example, the processing device can adjust, based on optical delay tuning data (e.g., built-in self-test (BIST) data), the at least one electrical component to modify at least one property of the at least one optical delay component.

Abstract: An optical wireless communication system and method An optical wireless communication (OWC) system comprises: a multiple input multiple output (MIMO) device configured to provide a plurality of signals each representing a respective data stream; conditioning circuitry configured to receive the plurality of signals from the MIMO device and process the plurality of signals to produce at least one conditioned signal representative of the data stream(s) and suitable for transmission using an OWC transmission device; an OWC transmission device comprising at least one transmitter for transmitting light and configured to be responsive to the at least one conditioned signal to transmit light representative of the data stream(s) using the at least one transmitter.

Abstract: System and methods of measuring nonlinear interference (NLI) on a per-span basis in an optical system with a plurality of spans are provided. The method includes steps of varying power based on phase sensitive detection method on a span under test of the plurality of spans; observing total noise, at an optical receiver, from all of the plurality of spans; and isolating noise for the span under test from the total noise based on the varying power. The optical system can be in-service with one or more traffic-carrying channels, and the varying power is small enough on the span under test which does not impact the one or more traffic-carrying channels.

Abstract: In some examples, high speed bidirectional OTDR-based testing may include transmitting data from a first end of a device under test (DUT) towards an optical time-domain reflectometer (OTDR) that is operatively connected to a second opposite end of the DUT. Further data that is transmitted by the OTDR may be received from the second opposite end of the DUT towards the first end of the DUT. Based on an amplitude of the further data, a direction of receiving of the further data may be adjusted towards a first receiver or towards a second receiver.

Abstract: In some examples, high speed bidirectional OTDR-based testing may include transmitting data from a first end of a device under test (DUT) towards an optical time-domain reflectometer (OTDR) that is operatively connected to a second opposite end of the DUT. Further data that is transmitted by the OTDR may be received from the second opposite end of the DUT towards the first end of the DUT. Based on an amplitude of the further data, a direction of receiving of the further data may be adjusted towards a first receiver or towards a second receiver.

Abstract: A finite rate of innovation (FRI) communications system includes a reference signal generator, an FRI modulator configured to apply an FRI kernel and encode information onto the reference signal, and a transmitter configured to transmit the encoded signal. The FRI kernel is one of a sinc function kernel or a Gaussian kernel. A receiver unit is configured to receive an encoded signal, convert the encoded signal into a digital signal, and demodulate and recover information from finite rate of innovation parameters in the digital signal.

Abstract: An analog signal processor includes a sampling unit configured to (i) filter, in the frequency domain, a received time domain analog signal into a low-frequency end of a corresponding frequency spectrum, (ii) sample the filtered analog signal at a frequency substantially higher than the low-frequency end, and (iii) spread quantization noise over an expanded Nyquist zone of the corresponding frequency spectrum. The processor further includes a noise shaping unit configured to shape the spread quantization noise out of the low-frequency end of the corresponding frequency spectrum such that the filtered analog signal and the shaped quantization noise are substantially separated in the frequency domain, and a quantization unit configured to apply delta-sigma modulation to the filtered analog signal using at least one quantization bit, and output a digitized bit stream that substantially follows the amplitude of the received time domain analog signal.

Abstract: Differentiating traffic signals from filler channels in optical networks includes obtaining power measurements of optical spectrum on an optical section in the optical network; analyzing the power measurements to differentiate signal type between traffic signals and Amplified Stimulated Emission (ASE) channel holders; and applying appropriate treatment to the optical spectrum based on the signal type. The analyzing is performed locally without any notification from upstream nodes of the optical spectrum.

Abstract: A method (200) of controlling compensation of chromatic dispersion in an optical transport network. The method comprises determining (202) whether a residual dispersion, RD, of a first path (3) within the network is within a defined RD range and if the RD of the first path is outside the defined RD range the method comprises identifying (204) a first tuneable dispersion compensation module, TDCM, crossed by the first path (3), configured to apply a respective value of dispersion compensation.

Abstract: A system for creating an adjustable delay in an optical signal. The system has an input interface for receiving an optical input signal. The system has a first optical modulator configured to shift the frequency of the optical input signal depending on a setting of the first optical modulator, thereby generating a modulated optical signal. The system includes at least two frequency selective reflectors configured to reflect the modulated optical signal, thereby providing a reflected signal. The system has a control circuit that adapts the setting of the first optical modulator such that a frequency shift of the optical input signal introduced by the first optical modulator is set by the control circuit. The frequency shift introduced by the first optical modulator corresponds to an operational frequency of one of the at least two frequency selective reflectors associated with the setting of the first optical modulator.

Abstract: An optical module of the present disclosure includes an optical element, a first optical component that is optically coupled to the optical element, a second optical component that is optically coupled to the first optical component, a receptacle to which an optical fiber that transmits the incident light to the second optical component is connected, a terminal unit that electrically outputs an output signal of the optical element to the outside, and a package that accommodates the optical element, the first optical component, and the second optical component and is provided with the receptacle on a first surface and the terminal unit on a second surface facing the first surface, wherein the wiring extends from the first surface side to the second surface side and electrically connects the second optical component and the terminal unit.