Abstract: Embodiments of the present disclosure provide a monitoring apparatus for an optical signal to noise ratio, a signal transmission apparatus and a receiver. White noise power of received signals is calculated according to noise power and power of pilot signals of the received signals in different polarization states, and influence of a nonlinear noise is excluded, thereby accurately estimating an optical signal to noise ratio, for example, with a calculation process being simple and an application range being relatively wide.

Abstract: A controller area network (CAN) comprising a plurality of CAN nodes that communicate via a CAN bus that comprises a fiber optical network. The fiber optical network uses a single fiber and a single wavelength for transmit and receive, and comprises a passive reflective optical star. The reflective optical star comprises an optical mixing rod having a mirror at one end. The other end of the reflective optical star is optically coupled to the transmitters and receivers of a plurality of optical-electrical media converters by way of respective high-isolation optical Y-couplers. Each CAN node produces electrical signals (in accordance with the CAN message-based protocol) which are converted into optical pulses that are broadcast to the fiber optical network. Those optical pulses are then reflected back to all CAN nodes by the reflective optical star.

Abstract: A transparent clock converter is interposed between a non-precision time protocol (non-PTP) enabled network node and other portions of the network. The transparent clock converter effectively converts the non-PTP node into a transparent clock node. In some embodiments the transparent clock converter includes physical layer devices, but not media access controllers.

Abstract: In a signal regeneration device in which recovery of a signal quality which has been degraded during transmission in optical communication and extension of a transmission distance are achieved, the most representative method of quantizing an optical phase is a phase sensitive amplifier (PSA) and a technique that utilizes an optical parametric process through use of a highly nonlinear optical medium, but there is a demand for a technique of quantizing an optical phase which is not accompanied with an optical parametric gain, has small-sized elements, is easily integrated, and does not require high power pump light.

Abstract: Methods and systems enable amplifying optical signals using a Bragg reflection waveguide (BRW) having second order optical nonlinearity to generate an optical pump by injection locking. The BRW may also be used for parametric amplification of optical signals using the optical pump. Feedback phase-power control may be performed to maximize output power.

Abstract: An optical switch (10) comprising: input ports (12, 14) arranged to receive optical signals from directions D1 to Dn; output ports (16, 18) arranged to output optical signals to the said directions; drop ports (20); add ports (22); a first switch array (24) arranged to receive from a first said input port (12) optical signals at a plurality of wavelengths, and comprising switch elements (26) each arranged to selectively direct optical signals to a respective drop port.

Abstract: A laser beacon may be attached to a vehicle, object, or personnel, or be incorporated into an existing vehicle optical emitter via software and/or hardware, that allows the vehicle, non-vehicle object, or associated personnel to be uniquely identified using a small telescope with a high-speed photodetector. The telescope may be an amateur telescope with a high speed-photodetector, which significantly reduces cost over more complex optical telescopes. Beacons may also be attached to objects that become space debris, such as fuel tanks, rocket stages, cubesat dispensers, and the like. The beacon may be suitable for use in space, in the air, on water, or on land.

Abstract: An optical receiver that receives a wavelength-multiplexed optical signal is disclosed. The optical receiver implements two or more PD elements each receiving an optical signal contained in the wavelength-multiplexed optical signal, a switch that selects one of photocurrents output from the PD elements, an I/V converter that converts the photocurrent into a voltage signal by a variable resistor whose resistance is adjusted for respective photocurrent, and a digital-to-analog converter. The optical receiver estimates the power of the optical signals from look-up-tables correlating the power of the optical signals with the digitally converted photocurrents at the selected resistance of the variable resistor.

Abstract: A system includes a detector array having a plurality of level detectors to monitor an optical input signal. Each level detector of the detector array operates in a different operating range, and each operating range for each level detector has a different saturation level and a different cutoff level based on a power level of the optical input signal. A controller monitors the plurality of level detectors of the detector array to detect a present power level for the optical input signal by selecting the operating range that is associated with the level detector operating between its saturation level and its cutoff level.

Abstract: It is made possible to accommodate a plurality of services and transmit each of the accommodated services to a corresponding transmission device. An optical transmitter according to an exemplary aspect of the present invention includes sub-carrier adjusting means for outputting sub-carriers to a plurality of output ports according to a control signal; encoding processing means for mapping client data on a plurality of output lanes according to the control signal; a plurality of modulation means for modulating the sub-carriers inputted through the output ports by client data inputted through the output lanes and outputting modulated signals; and control means for generating and outputting the control signal based on transmission information.

Abstract: A hybrid circuit-packet switch device includes a packet switch and a circuit switch. The circuit switch selectively passes, under control of a control logic, incoming data received at an optical input of the hybrid circuit-packet switch device to the packet switch or an optical output of the hybrid circuit-packet switch device.

Abstract: An optical transmitter includes: a splitter; a first optical modulator and a second optical modulator that modulate each of light beams split by the splitter; a first semiconductor optical amplifier (SOA) and a second SOA that are connected to a subsequent stage of the first optical modulator and a subsequent stage of the second optical modulator, respectively; a first detector and a second detector that detect light output intensity of the first SOA and light output intensity of the second SOA, respectively; a controller that sets gains of the first and second SOAs such that the first and second SOAs are equal in the light output intensity based on detection values of the first and second detectors; and a combiner that combines an output light beam of the first SOA and an output light beam of the second SOA.

Abstract: A visible light communication method performs visible light communication by using a visible light source. In searching a central frequency of the visible light source, a plurality of central-frequency training packets are sent, the central-frequency training packets including a plurality of central-frequency candidates, and one among the plurality of central-frequency candidates is selected as the central frequency of the visible light source based on a first decoding result on the plurality of central-frequency training packets. In searching a bandwidth of the visible light source, a plurality of bandwidth training packets are sent, the bandwidth training packets including a plurality of bandwidth candidates and the central frequency of the visible light source, and one among the plurality of bandwidth candidates is selected as the bandwidth of the visible light source based on a second decoding result on the plurality of bandwidth training packets.

Abstract: A wavelength allocation device includes a decision unit, a determination unit, and an evaluation unit. The decision unit decides whether a wavelength bandwidth of an optimum route for a demand has a free bandwidth to which the demand can be allocated. The determination unit allocates the demand to a bypass route, in the case that the wavelength bandwidth of the optimum route does not have the free bandwidth in the decision unit. The evaluation unit integrates the degree of influence of a section on the optimum route, which becomes a bypass factor, based on a difference in a route cost between the optimum route and the bypass route for the demand.

Abstract: Systems and techniques for concurrent optical network terminal simulation are described herein. A data packet may be received by an optical lint terminal. It may be determined that the data packet is associated with an optical network terminal simulation host. The data packet may be modified based on the determination. The modified data packet may be transmitted to a device.

Abstract: A processor of an optical transport apparatus is configured to transport an optical multiplexed signal between the optical transport apparatus and a counterpart apparatus by using a plurality of communication units; transmit an arbitrary optical wavelength from the optical multiplexed signal passing through ports by using a wavelength selective switch that has the ports respectively connected to the communication units; control a radio unit in the counterpart apparatus so as to change a frequency of the radio signal in the specified optical wavelength; and change a transmission band of the port through which the optical wavelength passes, according to a change of the frequency of the radio signal. The processor is configured to control an optical transmission unit of the counterpart apparatus so as to change a center wavelength of an optical wavelength passing through the port to a center wavelength of the changed transmission band of the port.

Abstract: The invention relates to quantum cryptography, and includes a communication system for transmitting a cryptographic key between the ends of a channel, including a transmitting node (Alice) comprising a beam splitter, an electro-optical attenuator, an amplitude modulator, a phase modulator, a storage line, a Faraday mirror, a synchronization detector; a receiving node (Bob) that includes avalanche photodiodes, a beam splitter, a circulator, a delay line, a phase modulator, a polarizing beam splitter, a Mach-Zehnder interferometer, and also a quantum channel for connecting these nodes. In this case, for the storage line is placed between the electro-optical phase modulator of the sender and the Faraday mirror. The limiting frequency of the laser pulse repetition at a fixed value of their width is increased, which makes it possible to use an autocompensation circuit at a frequency corresponding to the width of the laser pulse, which is the maximum possible result.

Abstract: Data security of a multi-dimensional code system is increased. An optical device is provided with a single input port; a splitter splitting an input light from the input port into a plurality of lights; a plurality of phase shifters each shifting one of the lights split by the splitter; a multi-port encoder/decoder inputting the lights whose phases are shifted by the phase shifters and generating spectral encoded codes; and a plurality of output ports outputting the spectral encoded codes generated by the multi-port encoder/decoder.

Abstract: The present invention discloses an apparatus and method for adaptive dispersion compensation, the apparatus comprising: a coarse-grain tunable dispersion compensator, a receiver with electric adaptive dispersion compensator, and a control logic unit. In the method, firstly it is to perform optical dispersion compensation for the input optical signals; then to perform electric dispersion compensation for the optical signals for which the optical dispersion compensation is performed; it is to detect the performance parameters of the receiving of the optical signals for which the electric dispersion compensation has been performed, and based on the performance parameters, it is to perform optical dispersion compensation adjustment for said input optical signals. With an optical de-multiplexer further, said apparatus can perform adaptive dispersion compensation for the multi-channel system.

Abstract: An optical data storage system and method of use thereof are presented. The optical data storage system includes one or more optical buffer modules connected in series. Each optical buffer module includes a cross connect. Each cross connect is connected, by a pair of inputs and outputs, to an optical data storage unit, for example, a fiber delay line, by a pair to either an optical packet network or a cross connect of a first adjacent buffer module in the series, and by a pair to a cross connect of a second adjacent buffer module in the series. The buffer module also includes a read signal output line which is connected to a read signal input line of the second adjacent buffer module for transmitting a read signal. A control module within each buffer module directs the passage of data through the cross connect.