Abstract: A visual light communication system is disclosed.

Abstract: Disclosed are an underwater optical communication aiming method and apparatus. The underwater optical communication aiming apparatus may include an optical communication module configured to transmit and receive laser beams and a plurality of acoustic modules spaced apart from one another at given intervals, disposed around the optical communication module, and configured to find a direction or relative distance of a counterpart light source under water. A direction of the optical communication module may be aimed at a counterpart light source found through the acoustic module in order to communicate with the counterpart light source by using the optical communication module.

Abstract: An optical submarine branching apparatus includes a first, second, and third switching unit. The first switching unit is connected to N first, second, and third optical fiber transmission lines connected to a first, second and third terminal stations, respectively, and switches a transmission route for a wavelength-multiplexed optical signal. The second switching unit is interposed on the N first optical fiber transmission lines between the first terminal station and the first switching unit, and switches a connection relation between in front of and behind a place where the second switching unit is interposed. The third switching unit is interposed on the N second optical fiber transmission lines between the second terminal station and the first switching unit, and switches a connection relation between in front of and behind a place where the third switching unit is interposed.

Abstract: A communication system includes a first communication gateway arranged proximate to a surface of a body of water and an underwater communication gateway. The underwater communication gateway is configured to receive data from a first underwater communication device using radio frequencies and the ethernet data link layer protocol, to convert the data received from the first underwater communication device from the ethernet data link layer protocol to the second data link layer protocol, and to transmit, using optical radiation and the second data link layer protocol, the data converted by the underwater communication gateway to the first communication gateway. The first communication gateway is configured to convert the data transmitted by the underwater communication gateway from the second data link layer protocol to the ethernet data link layer protocol, and to transmit, using the ethernet data link layer protocol, the data converted by the first communication device to a further communication device.

Abstract: An object to provide a submarine optical transmission apparatus capable of efficiently housing optical components and electric components. First component housing units can house either or both of an optical component and an electric component and are stacked in a Z-direction. A case can house the first component housing units and a longitudinal direction thereof is an X-direction. A heat dissipating member is disposed in the case and conducts heat generated in the first component housing units to the case.

Abstract: Disclosed is an undersea power routing device including a first coupling port, a high voltage converter a second coupling port. The first coupling port may be configured to be coupled to an electrical power conductor and fiber optical cables of an undersea branch cable. The high voltage converter may be coupled to the first coupling port and operable to connect to the electrical power conductor via the first coupling port. The high voltage converter may be further operable to convert a high voltage electrical power supplied by the electrical power conductor to an output voltage having a lower voltage electrical power than the high voltage electrical power. The second coupling port may be configured to couple the high voltage converter to an interconnect cable. The high voltage converter, when coupled to the interconnect cable, may be operable to distribute the lower voltage electrical power to the interconnect cable.

Abstract: An object to provide a submarine optical transmission apparatus capable of efficiently housing optical components and electric components. First component housing units can house either or both of an optical component and an electric component and are stacked in a Z-direction. A case can house the first component housing units and a longitudinal direction thereof is an X-direction. A heat dissipating member is disposed in the case and conducts heat generated in the first component housing units to the case.

Abstract: A system used to monitor and control a pool using a visual light communication system is disclosed.

Abstract: Embodiments of the present disclosure describe an underwater optical communication and illumination system employing laser diodes directly encoded with data, including spectrally efficient orthogonal frequency division multiplex quadrature amplitude modulation (QAM-OFDM) data. A broadband light source may be utilized to provide both illumination to an underwater field of interest and underwater optical communication from the field of interest to a remote location.

Abstract: A communication distribution unit, containing at least one power switch, said communication distribution unit comprising for an at least one consumer a power switch (4) based on a semiconductor design to switch on and off output lines (3) for the at least one consumer and the power switch (4) comprises at least one switching module (5).

Abstract: An apparatus is described which uses directly modulated InGaN Light-Emitting Diodes (LEDs) or InGaN lasers as the transmitters for an underwater data-communication device. The receiver uses automatic gain control to facilitate performance of the apparatus over a wide-range of distances and water turbidities.

Abstract: A method for creating an optical transmit signal includes creating an electrical discrete multi-tone signal according to digital input data carrying the information to be transmitted, the discrete multi-tone signal having a plurality of electrical partial signals, each electrical partial signal defining a sub-channel. Each electrical partial signal includes a sub-carrier at a predetermined sub-carrier frequency which is modulated according to a dedicated modulation scheme, so that a dedicated portion of the digital input data is included in each sub-channel. The method includes creating an optical signal by using the electrical discrete multi-tone signal as modulating signal for amplitude-modulating the intensity of an optical carrier signal. The method further includes bandpass-filtering the optical signal in order to create an optical single sideband or vestigial sideband transmit signal.

Abstract: A multi-hop ad hoc communications network may allow optical communications between underwater nodes. Each node may be fitted with environmental sensors. Each node may collect data from the sensors and transmit the data to other nodes in the network according to a time division multiple access (TDMA) scheme. The data may propagate through a series of child and parent nodes to reach a master node. The master node may have a wired connection for power and data transfer.

Abstract: [Problem] To provide an optical transmission/reception device, an optical communication system, an optical communication method, and a program which are capable of securing the confidentiality of information included in an optical signal even when the optical signal is transferred to a device that is not an original transmission destination device.

Abstract: An apparatus is described which uses directly modulated InGaN Light-Emitting Diodes (LEDs) or InGaN lasers as the transmitters for an underwater data-communication device. The receiver uses automatic gain control to facilitate performance of the apparatus over a wide-range of distances and water turbidities.

Abstract: A subsea data transmission cable for providing data communication with a subsea device installed at the ocean floor is provided. The subsea data transmission cable includes a first section including at least one electrical data line and a second section including at least one fiber optic data line. An intermediate conversion assembly is provided. The at least one electrical data line and the at least one fiber optic data line are terminated at the intermediate conversion assembly. A conversion device is disposed in a chamber of the intermediate conversion assembly. The conversion device includes an electrical interface connected to the at least one electrical data line and an optical interface connected to the at least one fiber optic data line. The conversion device is configured to convert an electrical data signal received at the electrical interface to an optical data signal for transmission via the optical interface and vice versa.

Abstract: The present disclosure provides short-term optical recovery systems and methods in coherent optical receivers to minimize recovery time for fault scenarios and signal reacquisition while maintaining robust signal acquisition. The short-term optical recovery systems and methods include special techniques and algorithms to minimize recovery time. The short-term optical recovery systems and methods include an expedited acquisition engine that includes a reference clock recovery, a compensator to remove chromatic dispersion, a burst framer, and a compensator to remove polarization dispersion. Importantly, the expedited acquisition engine uses a memory-oriented architecture to allow some properties of the acquisition engine to be stored during initial acquisition and, hence, later on be deployed in any fault scenario to further expedite recovery of a signal. The expedited acquisition engine leverages on a frequency aligned Local Oscillator (LO) as well as pre-calculated dispersion maps and equalizer coefficients.

Abstract: An underwater vehicle includes an optical beam operating system having a radiation generator, a radiation emission device, and a radiation transmission device connecting the radiation generator to the radiation emission device. The radiation generator is provided on or in the underwater vehicle. The radiation emission device can be brought to the water surface by the underwater vehicle.

Abstract: An undersea long-haul transmission system includes an optical fiber transmission span and a coherent detection and digital signal processing module for providing dispersion compensation. The transmission span includes at least one fiber pair comprising substantially equal lengths of a positive-dispersion first fiber and a negative-dispersion second fiber that are configured to provide a signal output at transmission distances greater than 10,000 km, in which the combined accumulated dispersion across the operating bandwidth does not exceed the dispersion-compensating capacity of the coherent detection and digital signal processing module. Further described is a fiber for use in an undersea long-haul transmission span. At a transmission wavelength of 1550 nm, the fiber has a dispersion coefficient in the range of ?16 to ?25 ps/nm·km, and a dispersion slope in the range of 0.04 to 0.02 ps/nm2·km.

Abstract: A system and method to broadcast an optical signal through an amorphous medium, including a primary emitter capable of producing a primary optical signal during at least one broadcast period and capable of transmitting the primary optical signal through the amorphous medium. A secondary emitter, separate from the primary emitter and in operation during at least a portion of the broadcast period, produces a secondary emission detectable by a detector during the broadcast period. A signal entrainment controller, in communication with the primary emitter and the secondary emitter, synchronizes the secondary emitter with the primary emitter to generate a resultant signal of higher intensity than the primary signal by itself.

Abstract: A method of optical underwater communications comprises applying a Fountain code to a plurality of data blocks. A sequence of optical data packets is transmitted through an underwater communications channel. Each optical data packet comprises one of the plurality of data blocks preceded by a preamble. The sequence of optical data packets transmitted through the underwater communication channel is received to generate a sequence of received data packets. The sequence of received data packets is sampled with the sampling clock to recover the plurality of data blocks.

Abstract: A transmitter includes an ultraviolet (UV) encoder conversion block that receives network data from a network interface to generate a conversion output. The UV conversion block converts the network data to a modulated signal that drives a plurality of multi-spectrum sources to generate the conversion output. A wave front optical component receives the conversion output from the UV conversion block and generates an output beam. The wave front optical component employs refraction compensation to mitigate absorption and scattering of the output beam in a liquid medium. An isotropic transmitter cluster transmits the output beam received from the wave front optical component as photon energy in the liquid medium. The isotropic transmitter cluster includes at least two transmitting nodes to facilitate transmission of the photon energy in a plurality of directions in the liquid medium.

Abstract: Systems and methods for method for data transport using secure reconfigurable branching units, including receiving signals from a first trunk terminal and a second trunk terminal by branching units. Broadcasting is prevented for secure information delivery by dividing, within the branching units, the one or more signals from the first trunk terminal and the second trunk terminal into two or more sections, and sending the two or More sections to an optical coupler. Signals may be received from a branch terminal by one or more branching units using two fiber pairs, and the signals from the branch terminals may be divided into two or more groups of optical sections, wherein one of the sections includes dummy light. The divided, signals from the first trunk terminal, the second trunk terminal, and dummy light from the branch terminal may be merged, and the merged signal sent to the branch terminal.

Abstract: The systems and methods described herein provide a reconfigurable, long-range, optical modem-based underwater communication network. In particular, the network provides a low power, low cost, and easy to deploy underwater optical communication system capable of being operated at long distances. Optical modem-based communication offer high data rate, omni-directional spatial communication in the visual spectrum. The omni-directional aspect of communication is advantageous because precise alignment of communication units may not be required. The optical modems may be deployed via unmanned underwater vehicles (UUVs) and physically connected by tethers.

Abstract: A system for signaling between elements in an undersea optical communication system including a cable signal generator. The signal generator includes line current modulation circuitry configured to impart modulation in line current provided on a power conductor of the transmission cable. A method of signaling between elements in an undersea optical communication system includes modulating a line current through an element and detecting the modulated current.

Abstract: An apparatus is described which uses directly modulated InGaN Light-Emitting Diodes (LEDs) or InGaN lasers as the transmitters for an underwater data-communication device. The receiver uses automatic gain control to facilitate performance of the apparatus over a wide-range of distances and water turbidities.

Abstract: An apparatus is described which uses directly modulated InGaN Light-Emitting Diodes (LEDs) or InGaN lasers as the transmitters for an underwater data-communication device. The receiver uses automatic gain control to facilitate performance of the apparatus over a wide-range of distances and water turbidities.

Abstract: Provided are an underwater communication device using visible light and an underwater communication method using the same. The underwater communication device using visible light, includes: an input unit converting a data signal received from the outside under water into an electrical signal; a transmitting unit converting the electrical signal into a visible light signal and emitting the visible light signal under water; a receiving unit recognizing the visible light signal under water and converting the visible light signal into the electrical signal; and an output unit converting the electrical signal into a data signal and outputting the data signal under water. Therefore, it is possible to provide an underwater communication device that may be implemented at low cost, perform wide band communication, and have excellent security.

Abstract: Methods, systems, and computer readable for providing smart underwater free space optical communications are provided. According to one aspect, a system for smart underwater free space optical communications is provided. The system includes a receiver. The receiver includes an optical detector array for detecting incident light under water. The receiver further includes a compound lens array located optically in front of the optical detector. The compound lens array includes lenses that steer incident light arriving at different angles to different portions of the optical detector array. A controller processes signals generated by the optical detector based on the incident light and controls an aspect of the underwater communications based on the steered incident light detected by the detector array.

Abstract: A method of optical underwater communications comprises applying a Fountain code to a plurality of data blocks. A sequence of optical data packets is transmitted through an underwater communications channel. Each optical data packet comprises one of the plurality of data blocks preceded by a preamble. The sequence of optical data packets transmitted through the underwater communication channel is received to generate a sequence of received data packets. The sequence of received data packets is sampled with the sampling clock to recover the plurality of data blocks.

Abstract: In general, a system and method provides secure communications between optical transceivers in an optical communication system. Two or more optical transceivers may be provisioned with one or more passcodes assigned to the transceivers, which may be used to indicate that received data traffic is intended for the transceivers. The transceivers may be configured to format data traffic with a secure version of the passcode in the overhead of the outbound signal and may be configured to determine if an inbound signal includes a secure version of the passcode provisioned in that transceiver. A transceiver may prevent data traffic from being read when the transceiver is not provisioned to receive data traffic with the embedded secure passcode and may insert an alternative maintenance signal (AMS) into an outbound signal in an opposite direction, at least temporarily, until the inbound signal includes the appropriate passcode.

Abstract: A subsea cable termination assembly for a subsea cable that includes an optical fiber for data transmission is provided. The subsea cable termination assembly includes a chamber that has a liquid tight seal against an ambient medium surrounding the subsea cable termination assembly, and a media converter arranged in the chamber. The media converter includes an optical interface adapted to be connected to an optical fiber of the subsea cable, and an electrical interface. The subsea cable termination assembly also includes an electric contact arranged outside the chamber and electrically connected to the electrical interface of the media converter arranged inside the chamber.

Abstract: A particular method includes applying light pulses to an optical fiber and receiving backscattered light at a phase-sensitive optical time domain reflectometry (OTDR) device. The backscattered light includes portions of the applied light pulses that are backscattered by the optical fiber. The method also includes determining a difference between the backscattered light and a backscatter pattern associated with the optical fiber. The method also includes determining a communication signal encoded in the backscattered light based on the difference, where the communication signal is encoded in the backscattered light responsive to mechanical waves applied to the optical fiber at a location remote from the phase-sensitive OTDR device.

Abstract: An undersea long-haul transmission system includes an optical fiber transmission span and a coherent detection and digital signal processing module for providing dispersion compensation. The transmission span includes at least one fiber pair comprising substantially equal lengths of a positive-dispersion first fiber and a negative-dispersion second fiber that are configured to provide a signal output at transmission distances greater than 10,000 km, in which the combined accumulated dispersion across the operating bandwidth does not exceed the dispersion-compensating capacity of the coherent detection and digital signal processing module. Further described is a fiber for use in an undersea long-haul transmission span. At a transmission wavelength of 1550 nm, the fiber has a dispersion coefficient in the range of ?16 to ?25 ps/nm·km, and a dispersion slope in the range of 0.04 to 0.02 ps/nm2·km.

Abstract: An underwater communication apparatus for performing an optical communication with an external device under water includes: a current control unit that modulates first data to be transmitted to the external device into a first current; and a light transmitting unit that transmits light with a wavelength of 450 to 500 nm corresponding to the first current to the external device.

Abstract: A network for transporting communication and power. The network comprises terminal stations branching units and subsea nodes connected to a branching unit, wherein at least one connection path between a terminal station and a first branching unit and between the first branching unit and a first subsea node is provided by means of optical fiber, and wherein said first subsea node is adapted to receive a plurality of wavelengths and provide at least one wavelength at an output thereof. The network comprises a first power supply connected to a first cable head of the trunk cable and at least a second power supply connected to a second cable head of the trunk cable. The first power supply and the at least second power supply, supply at least a minimum amount of electric current in the network either individually or in combination, under normal or faulty conditions.

Abstract: An underwater communications system is provided that transmits electromagnetic and/or magnetic signals to a remote receiver. The transmitter includes a data input. A digital data compressor compresses data to be transmitted. A modulator modulates compressed data onto a carrier signal. An electrically insulated, magnetic coupled antenna transmits the compressed, modulated signals. The receiver that has an electrically insulated, magnetic coupled antenna for receiving a compressed, modulated signal. A demodulator is provided for demodulating the signal to reveal compressed data. A de-compressor de-compresses the data. An appropriate human interface is provided to present transmitted data into text/audio/visible form. Similarly, the transmit system comprises appropriate audio/visual/text entry mechanisms.

Abstract: A simple visible light communication method and system that, underwater in an ordinary water-quality in which a diver is allowed to go under the water, are able to reliably communicate with a ship, or the like, above water while the diver is stopping at a safety stop position at a depth of 5 m in order to prevent occurrence of dysbarism. The visible light communication method and system us the visible light communication system that includes a transmitter and a receiver and that is usable underwater, and include at a transmitting side, modulating information to be transmitted to pseudo-white light that is adjusted to have a color temperature of 4000 to 10000K and a luminous flux of 550 to 1500 lumens and that is emitted from an LED, and transmitting the pseudo-white light; and, at a receiving side, extracting the information by demodulating the received pseudo-white light.

Abstract: A method and apparatus are present for managing a transmission of photons. The number of parameters for transmitting the photons as a beam in a liquid are identified using a number of characteristics of the liquid to form a number of selected parameters. The photons are transmitted in the liquid as the beam to a target using the number of selected parameters to form the transmission of the photons.

Abstract: Systems and methods for a reconfigurable, long-range, underwater data-communication network are described. The network provides a low cost, low power, lightweight, and easy to deploy underwater communication system capable of being operated at long distances. The network may include a cabled ocean observatory, which may be deployed underwater and connected to a surface buoy. The cabled ocean observatory may be connected to one or more removable underwater sensors via fiber optic cables. The underwater sensors may be disposed at underwater locations at long distances from the cabled ocean observatory. Fiber optic extension modules may be permanently connected to each end of the fiber optic cables. Each fiber optic extension module may include an optical transceiver, a power supply, and an inductive element for removably coupling an underwater sensor or the cabled ocean observatory to the fiber optic cable.

Abstract: An underwater data transmission system including arrays of nano-meter scaled photon emitters and sensors on an outer surface of an underwater platform. For the emitters, a laser is pulsed to correlate with data packets, providing a beam of photons at a prescribed frequency. Nano-scaled collecting lenses channel the incoming photons to photo-receptors located at a focal plane for the frequency at the base of each lens. A coating on the lenses absorbs photons at the frequency that are not aligned with the longitudinal axes of the lenses or tubes. Nano-wires connect the photo-receptors to a light intensity integrator. The integrator integrates the intensity over a surface area. The output of the integrator is fed to a signal processor to track and process the arriving digital packets.

Abstract: In general, a system and method provides secure communications between optical transceivers in an optical communication system. Two or more optical transceivers may be provisioned with one or more passcodes assigned to the transceivers, which may be used to indicate that received data traffic is intended for the transceivers. The transceivers may be configured to format data traffic with a secure version of the passcode in the overhead of the outbound signal and may be configured to determine if an inbound signal includes a secure version of the passcode provisioned in that transceiver. A transceiver may prevent data traffic from being read when the transceiver is not provisioned to receive data traffic with the embedded secure passcode and may insert an alternative maintenance signal (AMS) into an outbound signal in an opposite direction, at least temporarily, until the inbound signal includes the appropriate passcode.

Abstract: A subsea monitoring system.

Abstract: A data communications system is provided comprising a submersible home vessel, a submersible satellite vessel, and a flexible dielectric waveguide cable. The flexible dielectric waveguide cable comprises an exposed dielectric face configured to transmit electromagnetic millimeter wave radiation. The submersible home vessel comprises a transparent pressure boundary that is configured to be functionally transparent to electromagnetic millimeter wave radiation and to permit unguided propagation of the electromagnetic millimeter wave radiation. The submersible home vessel further comprises a coupling portion that is configured to secure the dielectric face in a position that enables the transmission of unguided millimeter wave radiation across the transparent pressure boundary to a MMW detector within the submersible home vessel. Additional embodiments are disclosed and claimed.

Abstract: An underwater data transmission system including arrays of nano-meter scaled photon emitters and sensors on an outer surface of an underwater platform. For the emitters, a laser is pulsed to correlate with data packets, providing a beam of photons at a prescribed frequency. Nano-scaled collecting lenses channel the incoming photons to photo-receptors located at a focal plane for the frequency at the base of each lens. A coating on the lenses absorbs photons at the frequency that are not aligned with the longitudinal axes of the lenses or tubes. Nano-wires connect the photo-receptors to a light intensity integrator. The integrator integrates the intensity over a surface area. The output of the integrator is fed to a signal processor to track and process the arriving digital packets.

Abstract: An underwater data transmission system including arrays of nano-meter scaled photon emitters and sensors on an outer surface of an underwater platform. For the emitters, a laser is pulsed to correlate with data packets, providing a beam of photons at a prescribed frequency. Nano-scaled collecting lenses channel the incoming photons to photo-receptors located at a focal plane for the frequency at the base of each lens. A coating on the lenses absorbs photons at the frequency that are not aligned with the longitudinal axes of the lenses or tubes. Nano-wires connect the photo-receptors to a light intensity integrator. The integrator integrates the intensity over a surface area. The output of the integrator is fed to a signal processor to track and process the arriving digital packets.

Abstract: The systems and methods of the invention provide for improved underwater communication systems. In particular, the systems and methods of the invention provide for improved underwater optical modems including optical transmitters and optical receivers that allow omni-directional transmission and reception of optical signals underwater and having a range of about 100 m and allowing data rates greater than 1 Mbit/s. The systems and methods of the invention also provide for underwater communication networks having a plurality of optical modems communicating with each other.

Abstract: The systems and methods of the invention provide for improved underwater communication systems. In particular, the systems and methods of the invention provide for improved underwater optical modems including optical transmitters and optical receivers that allow omni-directional transmission and reception of optical signals underwater and having a range of about 100 m and allowing data rates greater than 1 Mbit/s. The systems and methods of the invention also provide for underwater communication networks having a plurality of optical modems communicating with each other.

Abstract: Systems and methods for a reconfigurable, long-range, underwater data-communication network are described. The network provides a low cost, low power, lightweight, and easy to deploy underwater communication system capable of being operated at long distances. The network may include a cabled ocean observatory, which may be deployed underwater and connected to a surface buoy. The cabled ocean observatory may be connected to one or more removable underwater sensors via fiber optic cables. The underwater sensors may be disposed at underwater locations at long distances from the cabled ocean observatory. Fiber optic extension modules may be permanently connected to each end of the fiber optic cables. Each fiber optic extension module may include an optical transceiver, a power supply, and an inductive element for removably coupling an underwater sensor or the cabled ocean observatory to the fiber optic cable.

Abstract: According to one embodiment, an infrared signal decode circuit includes: a comparator; a correlation signal generator generating a sum of a first detection signal and a second detection signal as a correlation signal, the first detection signal being obtained by performing an absolute value calculation on a first correlation signal, the second detection signal being obtained by performing an absolute value calculation on a second correlation signal, the first correlation signal corresponding to a correlation between a binary signal and a first reference signal with a frequency substantially identical to a base frequency of a subcarrier of an infrared signal, the second correlation signal corresponding to a correlation between the binary signal and a second reference signal with a phase that differ from a phase of the first reference signal by 90 degrees; and a decoder binarizing the correlation signal generated by the correlation signal generator.