Abstract: Optical signal to noise ratios that more accurately characterize optical link noise are determined. As noise induced by an optical receiver does not generally vary with an input optical signal power, a power of an incoming optical signal is varied at the receiver. A resulting variation in noise measure represents a variation in link noise and does not include any variation caused by receiver noise, as receiver noise does not generally vary with optical signal power. Thus, the contribution of optical link noise can be discerned from other noise induced by the receiver itself. A more accurate characterization of optical link performance is thus provided.

Abstract: Methods of operating an optical communication system in coherent optical transmissions for metro applications. Relative to conventional solutions, the optical communication system can be implemented with reduced cost and can operate with reduced power consumption, while maintaining high data rate performance (e.g., 100G). Furthermore, a programmable transceiver enables compatibility with a range of different types of optical networks having varying performance and power tradeoffs. In one embodiment, the optical communication system uses 100 Gb/s dual-polarization 16-point quadrature amplitude modulation (DP-16QAM) with non-linear pre-compensation of Indium Phosphide (InP) optics for low power consumption.

Abstract: A service mapping processing method for an optical transport network, an apparatus, and a system are provided, where the method includes: generating mapping adaptation indication information according to a mapping granularity of a to-be-carried LO ODU, where the mapping granularity is M×g bytes, M is a quantity of timeslots occupied by the to-be-carried LO ODU in an OPUCn, g is a size of a mapping granularity corresponding to each timeslot of the timeslots occupied by the LO ODU, and g is a positive integer greater than 1; mapping, according to the mapping adaptation indication information, the to-be-carried LO ODU to an ODTUCn.M payload area; encapsulating the mapping adaptation indication information into the ODTUCn.M overhead area; encapsulating the ODTUCn.M into an OTUCn; and sending the OTUCn to a receive end device. The method avoids that OTUCns that use different mapping granularities cannot interwork between a receive end and a transmit end.

Abstract: Systems, methods, and devices for infrared (IR) communications in accordance with embodiments of the invention are disclosed. In one embodiment, a first infrared (IR) device configured for real time mapping comprises: a mapping module; a communication module; an IR receiver configured to receive an IR signal transmitted from at least one second IR device; a processor operatively connected to the mapping module, communication module, and IR receiver; and memory storing a program comprising instructions that cause the first IR device to: capture map data using the mapping module; transmit a request for an IR signal using the communication module; scan for IR signals using the IR receiver; receive an IR signal, from the at least one second IR device, using the IR receiver; and validate the at least one second IR device to a location by mapping the received IR signal to a position on the map data.

Abstract: The concepts and technologies disclosed herein are directed to quantum tampering threat management. According to one aspect of the concepts and technologies disclosed herein, a quantum security manager (“Q-SM”) can monitor a plurality of quantum channels for tampering. The Q-SM can detect tampering on a quantum channel of the plurality of quantum channels. The Q-SM can provide tampering monitoring statistics to a software-defined network (“SDN”) that, in turn, notifies a quantum security operations center (“Q-SOC”) about the tampering on the quantum channel. The Q-SM can receive threat mitigation instructions from the Q-SOC. The threat mitigation instructions can instruct the Q-SM how to counter the tampering on the quantum channel. The Q-SM can perform one or more actions in accordance with the threat mitigation instructions to counter the tampering on the quantum channel.

Abstract: A free space optical (FSO) communication node communicates via an FSO link with a remote FSO communication node that moves relative to the FSO node. The FSO node may be highly directional, and transmit (Tx) and receive (Rx) beams of the FSO node may share optical paths (at least in part). Instead of directing a Tx beam along a point ahead angle relative to a Rx beam (which may result in undesirable Rx coupling losses), the Tx beam is directed based on the point ahead angle and a point ahead offset angle. The point ahead offset angle modifies the point ahead angle to reduce Rx coupling losses while keeping Tx pointing losses at least low enough to maintain the FSO link. In some cases, due to the point ahead offset angle, the Tx direction minimizes a sum of the Rx coupling losses and the Tx pointing losses.

Abstract: A wavelength dispersion amount estimation apparatus includes a correlation signal generation unit configured to generate, from a receive signal, a first signal including a main signal of the receive signal and a second signal, which includes an image signal corresponding to the main signal, with a shift by a baud rate of the receive signal relative to the first signal in a frequency domain, a correlation calculation unit configured to calculate a cross correlation of the first signal and the second signal, and a dispersion amount calculation unit configured to calculate a wavelength dispersion amount, based on a position of a peak of the cross correlation.

Abstract: An illustrative system obtains connectivity data for an optical wireless communication link between an optical wireless signal transmitter implemented on a first in-flight aerial vehicle and an optical wireless signal receiver implemented on a second in-flight aerial vehicle, determines, based on the connectivity data, a status of the optical wireless communication link, and performs, based on the status of the optical wireless communication link, a connectivity management operation configured to facilitate connectivity of the optical wireless signal receiver with the optical wireless signal transmitter by way of the optical wireless communication link. Corresponding methods and systems are also described.

Abstract: An electronic device may be provisioned with an infrared (IR) light-emitting diode (LED) configured to externally transmit identifying information that particularly identifies the device, such as the device serial number, to outside of the device. A companion portable IR LED reader may be used to systematically scan a row or shelf or rack of electronic devices to read the respective communication signals transmitted from each of the respective devices, thereby enabling quick and accurate physical identification of the devices in a system/datacenter and inhibiting the unnecessary removal of an incorrect or misidentified device for replacement.

Abstract: A quantum communications system may include a transmitter node, a receiver node, and a quantum communications channel coupling the transmitter node and receiver node. The transmitter node may include a pulse transmitter and a pulse divider downstream therefrom. The pulse divider may be configured to divide each pulse having a plurality of X photons into a plurality of Y time bins with Y>X. The receiver node may include a pulse recombiner and a pulse receiver downstream from the pulse recombiner.

Abstract: An example system includes a first network device having first circuitry. The first network device is configured to perform operations including receiving data to be transmitted to a second network device over an optical communications network, and transmitting first information and second information to the second device. The first information is indicative of the data, and is transmitted using a first communications link of the optical communications network and using a first subset of optical subcarriers. The second information is indicative of the data, and is transmitted using a second communications link of the optical communications network and using a second subset of optical subcarriers. The first subset of optical subcarriers is different from the second subset of optical subcarriers.

Abstract: A free space optical FSO space data transmission system includes a first ground or aeronautical optical terminal, a second optical terminal housed on board a satellite, and a relay platform. The relay platform is configured so as to move at an altitude higher than that of clouds and atmospheric turbulence, so as to receive the data transmitted by the first terminal in the MWIR/LWIR domain of long wave infrared LWIR wavelengths and/or medium wave infrared MWIR wavelengths, and retransmit the received data to the second terminal in the domain of short wave infrared SWIR wavelengths, and/or receive the data transmitted by the second terminal in the domain of short wave infrared SWIR wavelengths, and retransmit the received data to the first terminal in the MWIR/LWIR domain of long wave infrared LWIR wavelengths and/or medium wave infrared MWIR wavelengths.

Abstract: Systems and methods include receiving first power snapshot from a receiving end of a foreign controlled link of the one or more foreign controlled optical links when there are no faults thereon; responsive to obtaining second power snapshot from the receiving end of the foreign controlled link, detecting a fault on one of at least one channel and part of the spectrum traversing the foreign controlled link; correlating the second power snapshot with the first power snapshots; and raising an indication of fault for the foreign controlled link based on the correlating.

Abstract: An optical system, comprising a first wavelength conversion module to: adjust a power of a first pump wavelength; couple an input signal with the first pump wavelength to generate a first coupled signal; perform a first wavelength conversion of the first coupled signal to generate a first wavelength converted signal, the power of the first pump wavelength is adjusted such that the first wavelength conversion is performed with 0 dB conversion efficiency; the optical amplifier to amplify the first wavelength converted signal; a second wavelength conversion module to: adjust a power of a second pump wavelength; couple the amplified first wavelength converted signal with the second pump wavelength to generate a second coupled signal; perform a second wavelength conversion of the second coupled signal to generate a second wavelength converted signal with 0 dB conversion efficiency.

Abstract: A free space optical communications transmitter terminal including an optical source arranged to provide a first beam of light encoding information to be communicated; an optical source arranged to provide photons encoding bits of a key of a Quantum Key Distribution protocol; and an optics arrangement. The first beam and the photons are linearly polarised. The optics arrangement is configured to combine the first beam and the photons into a single, second, beam to be transmitted to a receiver terminal; and transform the linear polarisation of the first beam into one of left and right circular polarisation and transform the linear polarisation of the photons into the other of left and right circular polarisation. A receiver terminal receives the second beam, transforms the circular polarisations into orthogonal linear polarisations, and filters out the linear polarisation of the first beam to allow the photons to pass to a single photon detector.

Abstract: Optical protection switching apparatus (10), for a single fibre bidirectional WDM optical ring, comprising: first (12) and second (14) ports for coupling to first and second adjacent portions of a single fibre bidirectional WDM optical ring; an optical splitter (16) comprising an input to receive a WDM aggregate optical signal, and first and second outputs coupled to the first and second ports; an optical switch (108) between the second output and the second port; and processing circuitry (24) to receive at least one of an indication of transmission continuity in the optical ring and an indication of transmission discontinuity in the optical ring, and to generate a switch control signal (20) comprising instructions to cause the optical switch to be open when there is transmission continuity in the optical ring and to cause the optical switch to be closed when there is transmission discontinuity in the optical ring.

Abstract: A quantum communications system includes a quantum key generation system having a photonic quantum bit generator, a low loss dispersion limiting fiber having a length L, for example greater than 200 km, and a photon detector unit and a communications network having a signal generator, a signal channel, and a signal receiver. The low loss dispersion limiting fiber extends between and optically couples the photonic quantum bit generator and the photon detector unit. Further, the low loss dispersion limiting fiber is structurally configured to limit dispersion at an absolute dispersion rate of about 9 ps/(nm)km or less, and preferably 0.5 ps/(nm)km or less, and induce attenuation at an attenuation rate of about 0.175 dB/km or less such that the quantum key bit information of a plurality of photons output by the one or more photonic quantum bit generators is receivable at the photon detector unit at a bit rate of at least 10 Gbit/sec.

Abstract: An optical modulation system comprises a signal source configured to generate an amplitude modulated electrical signal having a bandwidth and divided into frequency components comprising at least a first frequency component covering a first portion of the bandwidth and a second frequency component covering a second portion of the bandwidth; and an electro-optic modulator for receiving an input optical signal, the modulator having a first optical path and a second optical path, the input optical signal being divided between the first optical path and the second optical path and recombined after propagation along the first optical path and the second optical path to produce an output optical signal, and at least one of the first optical path and the second optical path comprising a phase shifter comprising a pair of electrodes in which each electrode is configured to receive a driving signal; wherein the or each phase shifter is coupled to the signal source to receive at least one of said frequency components a

Abstract: The invention relates to the field of Free Space Optics (FSO), more specifically it is directed to: a method of obtaining a connection between at least two optical signal nodes, of a FSO, communication system each node comprising a transmitting device and receiving device; and transmitting via the transmitting device of a first node, a first diverged optical signal into an optical medium; receiving at the receiving device of the second node the first diverged optical signal and transmitting via the transmitting device of the second node a second diverged signal to the receiving device of the first node to establish a location of said first node establishing a connection, after which; the first node switches from the diverged optical signal to a narrower optical signal for the transmission of data via the connection.

Abstract: Techniques for automatically determining an input resistance of an optical modulator and configuring a modulation current source can include applying a first bias current to an input of the optical transmitter and measuring a corresponding first voltage at the input of the optical transmitter. A second bias current can also be applied to the input of the optical transmitter and a corresponding second voltage at the input of the optical transmitter can be measured. An input resistance of the specific optical transmitter can be determined from the difference between the first and second voltages divided by the difference between the first and second bias currents. The technique can further include setting one or more configuration settings in one or more registers of a modulation current source based on the determined input resistance of the optical transmitter.