Abstract: An optical communications apparatus includes a branching unit and a switching module. The branching unit is configured to be connected to first, second, and third optical cables each including an optical fiber. The branching unit includes a branch optical path configured to route a fixed pre-determined range of wavelengths that are input to the branching unit from the optical fiber of the first cable to the optical fiber of the third cable. The switching module includes at least one optical switch having a bypass configuration and a branch connecting configuration. In the bypass configuration, a connection via the branch optical path to a distal portion of the third cable is bypassed. In the branch connecting configuration, the branch optical path is enabled so that the pre-determined range of wavelengths that are input to the branching unit are routed to the optical fiber of the distal portion of the third cable.

Abstract: A submarine optical communication system using one or more power feed converters for power delivery to repeaters. Power feed equipment located one or more a landmasses is coupled to a power conductor of an optical cable for powering repeaters coupled to cable. One or more power feed converter(s) are coupled to the power conductor for converting current from power feed equipment to a constant output current or voltage for powering other repeaters coupled to the cable. Embodiments are robust to shunts of the power conductor.

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: A bidirectional submarine transmission using unidirectional amplification transmits first and second communication signals bidirectional to each other over a repeater path with common end-to-end points, the repeater path includes a single unidirectional amplifier, the repeater path has a first branch path for the first communication signal through the single amplifier and a second branch path for the second communication signal through the single unidirectional amplifier, the first and second communication signals originating and leaving opposite ends of the repeater path, respectively.

Abstract: An optical transmission system is described. The transmission system comprises a plurality of modules that include signal repeaters at each end. Within each module, optical signals are propagated between the repeaters through free space. Adjacent modules are connected by optical fibers to enable optical transmission therebetween. Adjacent modules are mechanically coupled with a flexible joint.

Abstract: An apparatus for providing communications between a first device disposed at a tubular and a second device, the tubular having tubular sections and being configured to be disposed in a borehole penetrating the earth, the apparatus including: a first optical coupler configured to be coupled to a first tubular section and configured to be in optical communication with the first device using a first optical transmission medium disposed at the first tubular section; and a second optical coupler configured to be coupled to a second tubular section and configured to be in optical communication with the second device using a second optical transmission medium disposed at the second tubular section; wherein the first optical coupler is configured to be perimetrically disposed about the second optical coupler to be in communication with the second optical coupler to provide the communications between the first device and the second device.

Abstract: A system to convert upstream burst mode data into continuous mode data in a passive optical network (PON) is provided herein. The system includes a burst mode Serializer/Deserializer (SerDes) that recovers a clock and burst mode data from an Optical Network Unit (ONU). The burst mode unit recovers the burst mode data based on a start time of burst mode data transmission by the ONU and a round-trip time between the ONU and an Optical Line Terminal (OLT). The system further includes a continuous mode SerDes that is coupled to the burst mode SerDes. The continuous mode SerDes is configured to receive the recovered clock and recovered burst mode data from the burst mode SerDes and convert the burst mode data into continuous mode data by buffering and padding the burst mode data based on the recovered clock. The continuous mode Serdes is configured to transmit the continuous mode data to the OLT.

Abstract: Described herein are embodiments of displays which may be used in high pressure environments, e.g., in underwater environments, and systems which utilize such displays. In some embodiments, a system comprises at least one electronic device comprising an optical output, a first optical interface to couple the optical output to an optical transmission medium, a second optical interface coupled to the optical transmission medium, and a display coupled to the second optical interface. In some embodiments the second optical interface comprises a material having a graded index of refraction, and the display comprises an optically transmissive material coupled to the second optical interface to transmit an image from the second optical interface to a reflective surface.

Abstract: The present invention relates to a system that provides underwater data transfer between two remote client systems via an underwater cabled network operable. The cabled network includes at least two data access points each having an access point electromagnetic transceiver; and each remote client system comprising a client electromagnetic transceiver. Each data access point is operable to transfer data between said cabled network and one of said client electromagnetic transceivers via one of inductive magnetic and electromagnetic signals carried through the water.

Abstract: There are provided surge protection devices for undersea optical repeaters. An optical repeater drive circuit incorporating a diode chain design includes a diode array formed of a plurality of banks of two or more parallel forward-biased diodes, each diode in a given bank being in electrical contact with all the diodes in adjacent banks; and, optical repeater control circuitry connected in parallel with the diode array. A component for providing surge protection to an optical repeater incorporates a substrate formed of an insulating material and a first substantially planar conducting coil embedded within the substrate.

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: The present invention relates to a system that provides underwater data transfer to an underwater communications network operable to carry a high bandwidth multiplexed data stream. The cabled network includes at least one data access point having an access point electromagnetic transceiver; and at least one remote client system comprising a client electromagnetic transceiver. The at least one data access point transfers data between said cabled network and said client electromagnetic transceiver via one of inductive magnetic and electromagnetic signals carried through the water.

Abstract: Upon transmission path monitoring, when a monitoring signal responded by one of optical repeaters provided in a main signal transmission path is superposed on an optical main signal and sent out to the main signal transmission path, the optical main signal is branched to optical fibers, that are optical transmission paths, provided separately from the main signal transmission path and each provided with optical repeaters corresponding to the optical repeaters provided in the main signal transmission path, an optical main signal is selected from a desired optical fiber to be monitored from among the optical transmission paths and the monitoring signal is extracted from the optical main signal selected, thereby checking the quality of the desired optical fiber.

Abstract: The invention relates to a modulation scheme for optical communication, in particular for fiber optics communication. According to invention, an optical signal is generated, both phase and polarization of which modulated in dependency of the data to be transmitted. Preferably, the generated optical signal comprises a sequence of symbols (22a-22k) and each symbol (22a-22k) has one of two different phase states and one of two different orthogonal polarization states. Bits of the data stream to be transmitted are encoded both in the phase state of a symbol (or in the phase state difference between subsequent symbols) and in the polarization state of the symbol (or in the polarization state difference between the subsequent symbols).

Abstract: An undersea repeaterless optical transmission system is disclosed including first and second stations connected by a communication link which may comprise one or more optical fibers. The system further includes a dedicated Raman pumping path originating from a third intermediate station and interacting with the communication link at an undersea body positioned between the first and second stations. This dedicated Raman pumping path may comprise one or more optical fibers. Communications signals are propagated only between the first and second stations, while the third intermediate station provides only Raman pumping via the pumping path which is used to boost signal power in the communication link between the first and second stations. By limiting this pumping path to Raman pumping only substantially more pumping power can be provided through the path since power is not limited by the equation of a communications signal.

Abstract: The present invention relates to a system that provides flexible data access to a wired underwater communications network through an electromagnetic, non-conductive connection. An underwater data access point is described wherein data access to a cabled network is provided through an electromagnetic connection. An inductive connector system may also be provided to allow transfer of data and/or power between a data access point and a client system.

Abstract: An underwater optical communications system and method particularly suitable for use in communications with automated equipment. A series of light beacons are dispersed throughout a communications zone. The light beacons are each provided with a plurality of light-emitting elements and light receiving elements which are positioned so that each beacon within the communications zone emits light in a plurality of directions and receives light from a plurality of directions. A submersible craft is similarly provided with light emitting elements and light receiving elements. The submersible craft is thus always in optical communication with one or more beacons when in the communications zone, regardless of the orientation of the craft and regardless of the position of the craft within the communications zone.

Abstract: A method and apparatus is provided for applying an electroding tone to a power conductor located in an undersea optical cable employed in an undersea optical transmission system having at least one repeater. The method begins by applying a DC line current to the power conductor. The DC line current has a value sufficient to power the repeater and less than a value sufficient to power the repeater and to perform electroding. An AC current is impressed on the DC line current at a prescribed frequency and a peak-to-peak amplitude ranging from zero and a prescribed value to generate the tone. The impression or application of the AC current is terminated after a period of time at least sufficient to locate the optical cable or an optical cable fault.

Abstract: A communication system including a repeatered trunk path and one or more unrepeatered branch segments coupled to the trunk path through associated submarine branching units. Each of the branch segments may be configured to carry at least the same channel capacity as the trunk path and may have a length greater than the average repeater spacing in the trunk path.

Abstract: An optical amplifier module contains at least one optical amplifier. The module includes an internal housing having an outer dimension substantially equal to an outer dimension of an internal fiber splice housing of an undersea optical fiber cable joint. The internal housing includes a pair of opposing end faces each having a retaining element for retaining the internal housing within an outer housing of the undersea optical fiber cable joint. The internal housing also includes a sidewall interconnecting the opposing end faces, which extends between the opposing end faces in a longitudinal direction. The sidewall includes a receptacle portion having a plurality of thru-holes each being sized to receive a passive optical component employed in an optical amplifier.

Abstract: An undersea optical repeater is provided. The repeater includes a pressure vessel for use in an undersea environment. The pressure vessel includes a pressure housing and at least two cable reeving elements disposed on opposing ends of the pressure housing for respectively receiving ends of optical cables that each include an electrical conductor therein. The cable receiving elements are adapted to be in electrical contact with the respective electrical conductors in the optical cables. At least one optical amplifier is located in the pressure vessel. The optical amplifier includes at least one electrical component adapted to receive electrical power from the electrical conductors in the optical cables. The pressure housing includes a dielectric layer having sufficient dielectric properties for electrically isolating the cable receiving elements from one another to provide a voltage thereacross.

Abstract: There are provided surge protection devices for undersea optical repeaters. An optical repeater drive circuit incorporating a diode chain design includes a diode array formed of a plurality of banks of two or more parallel forward-biased diodes, each diode in a given bank being in electrical contact with all the diodes in adjacent banks; and, optical repeater control circuitry connected in parallel with the diode array. A component for providing surge protection to an optical repeater incorporates a substrate formed of an insulating material and a first substantially planar conducting coil embedded within the substrate.

Abstract: An optical amplifier module is provided that contains at least one optical amplifier. The module includes an internal housing having an outer dimension substantially equal to an outer dimension of an internal fiber splice housing of an undersea optical fiber factory cable joint. The internal housing includes a pair of opposing end faces each having a retaining element for retaining the internal housing within an outer housing of the undersea optical fiber cable joint. The internal housing also includes a sidewall interconnecting the opposing end faces, which extends between the opposing end faces in a longitudinal direction. The sidewall includes a receptacle portion having a plurality of thru-holes each being sized to receive a passive optical component employed in an optical amplifier. The module also includes at least one circuit board on which reside electronics associated with the optical amplifier.

Abstract: In each of a plurality of submarine observation apparatus (1 to n), a branching unit (63) branches fixed-wavelength light (?1) from an incoming wavelength-multiplexed light signal. An observation signal modulating unit (64) modulates the intensity of the branched fixed-wavelength light (?1) with observation information multiplexed by an observation signal multiplex unit (61). A combining unit (65) combines light signals (?2) to (?n) passing through the branching unit (63) and the fixed-wavelength light (?1a) modulated by the observation signal modulating unit (64) into a composite light signal, and outputs it to an optical fiber (12a). Therefore, in each of the plurality of submarine observation apparatus (1 to n), there is no necessity for providing a wavelength-division-multiplexing-transmission optical transmitter which requires high wavelength stability.

Abstract: A method for entering a market with high barriers to entry and a plurality of proprietary business elements includes converting at least one of the business elements into a universal business element that can accept a wide variety of inputs from other business elements, while converting a remaining one of the plurality of business elements to commoditized business elements. In addition, a market of a resulting business is limited so that the resulting business straddles a gap between two subdivisions of the market. Thus, a combination of technology and market division enables conversion of otherwise proprietary system to commodity equipment that can work with a wide variety of existing vendor equipment while competing technologically with highly engineered solutions.

Abstract: System and method for re-routing internal power for reducing voltage requirements of a submarine transmission system. A power supply supplies power to a bridge rectifier circuit (10) the latter biasing a plurality of Zener diodes (11; 12; 13; 14; 15; 16) which are connected in parallel arrangement with respective optical amplifiers (21; 22; 23; 24; 25; 26). The bridge rectifier circuit (10) is arranged such that a first predetermined number of Zener diodes (23; 24; 25; 26) are biased in forward bias direction thus operating as normal diodes with a low voltage drop, whereas a second predetermined number of Zener diodes (21; 22) are biased in reverse or powering direction thus powering respective optical amplifiers.

Abstract: A power feed arrangement for aggregate segments of a communications system is disclosed. In embodiments of the invention, cables are used to communicatively connect a number of landmasses, where the cables also serve to carry electrical power to devices connected along lengths of the cables. A first cable is connected to first and second landmasses, while a second cable is connected to second and third landmasses. On the second landmass, the electrical power conductors of the first and second cables are electrically connected to one another, and pieces of power feed equipment located on said first and third landmasses are used to supply electrical power to devices located along lengths of the first and second cables. Alternative embodiments are also disclosed.

Abstract: A System and Method for Providing an Improved Standby Mode for Infrared Data Transceivers is disclosed. Standby Mode for Infrared Data Transceivers. The device and system of the present invention includes a discovery signal receiver and power actuator module that consumes a fraction of the power of a conventional Ir transceiver system. The preferred device and system may be integral to a conventional Ir transceiver, or it may be a stand-alone system or device. Furthermore, the device and system are configured to activate full power to the Ir transceiver system upon recognition of an Ir discovery signal, and this power-up signal might also be user-initiated in some preferred embodiments. The preferred switch means for providing full power to the Ir transceiver system is in an open position while the Ir-enabled appliance is in a standby or sleep mode. The preferred device and system recognize a 9600 baud Ir discovery signal.

Abstract: Repeaters for use in amplifying optical data signals transmitted through undersea fiber optic cables are disclosed. Raman amplification schemes using 100 or more pump lasers are integrated into industry standard sized pressure vessels for amplifying optical data signals transmitted through one or more fiber optic pairs. Such repeaters include high density packaging to permit numerous active and passive optical components, as well as significant lengths of optical fiber, to reside within legacy sized pressure vessels.

Abstract: A power feed arrangement for aggregate segments of a communications system is disclosed. In embodiments of the invention, cables are used to communicatively connect a number of landmasses, where the cables also serve to carry electrical power to devices connected along lengths of the cables. A first cable is connected to first and second landmasses, while a second cable is connected to second and third landmasses. On the second landmass, the electrical power conductors of the first and second cables are electrically connected to one another, and pieces of power feed equipment located on said first and third landmasses are used to supply electrical power to devices located along lengths of the first and second cables. Alternative embodiments are also disclosed.

Abstract: If a repeater supervisory control (SV), a pre-emphasis automatic adjustment (PE), a receiving side threshold value automatic adjustment (Vth), a transmitting side dispersion compensation value setting (VDC(T)), and a receiving side dispersion compensation value setting (VDC(R)) are executed for an optical main signal, these controls are executed in the above described priority order. Accordingly, if the controls are independently executed, or if two or more controls simultaneously occur, a control with a higher priority is executed. In this way, a transmission quality of an optical signal is prevented from being badly influenced as a result that the controls are simultaneously executed.

Abstract: High power repeaters for use in amplifying optical data signals transmitted through undersea fiber optic cables are disclosed. Raman amplification schemes using 100 or more pump lasers are integrated into industry standard sized pressure vessels for amplifying optical data signals transmitted through one or more fiber optic pairs. Other repeater features include high density packaging, efficient power distribution, and component sharing.

Abstract: A system for delivering optical signals to and from an undersea optical cable may include a cable landing station connected to the undersea optical cable and configured to convey a wavelength division multiplexed optical signal from the undersea optical cable. The system may also include a point of presence that includes wavelength division multiplexing equipment configured to convert the wavelength division multiplexed optical signal to a number of optical channels. At least one terrestrial optical fiber may be coupled between the cable landing station and the point of presence to transport the wavelength division multiplexed optical signal from the cable landing station to the point of presence.

Abstract: A method and an apparatus for optical transmission line power feed interference compensation for compensating for an electrical interference signal in a power feed conductor (12; 52) and in an associated second conductor (14; 54). The interference signal may be produced by electromagnetic induction or by local variation in earth potential. The compensation is performed by producing a variable compensation signal from an electrical interference signal produced in the second conductor and inputting the variable compensation signal onto the power feed conductor, in order substantially to compensate for or cancel the electrical interference signal produced in the power feed conductor.

Abstract: An undersea optical repeater is provided that includes a pressure vessel for use in an undersea environment. The pressure vessel has at least two cable-receiving elements for respectively receiving ends of optical cables that each includes an electrical conductor therein. At least one optical amplifier is located in the pressure vessel. The optical amplifier includes at least one electrical component adapted to receive electrical power from the electrical conductors in the optical cables. A dielectric envelope surrounds the pressure vessel to provide a hermetic seal therewith. The envelope includes a dielectric overmold surrounding at least a portion of the pressure vessel.

Abstract: An optical submarine communication system has a land cable connected to a terminal apparatus which is installed on land near the seashore for transmitting an optical signal and electric power. The land cable is connected to an optical submarine cable through a beach manhole, and a repeater is connected to the optical submarine cable. The optical submarine communication system has a surge suppressor provided on the land cable, whereby a surge generated from the terminal apparatus side because of a lightning stroke or an insulation failure is suppressed and prevented from reaching and damaging the repeater.

Abstract: A pressure vessel is provided for use in an undersea environment. The pressure vessel including a pressure housing and at least two cable receiving elements disposed on opposing ends of the pressure housing for respectively receiving ends of optical cables that each include an electrical conductor therein, said cable receiving elements adapted to be in electrical contact with the respective electrical conductors in the optical cables. At least one optical amplifier is located in the pressure vessel. The optical amplifier includes at least one electrical component adapted to receive electrical power from the electrical conductors in the optical cables. The pressure vessel also includes an electrically insulating element electrically isolating at least one of the cable receiving elements from the pressure housing.

Abstract: An optical amplifier module is provided that contains at least one optical amplifier. The module includes an internal housing having an outer dimension substantially equal to an outer dimension of an internal fiber splice housing of an undersea optical fiber cable joint. The internal housing includes a pair of opposing end faces each having a retaining element for retaining the internal housing within an outer housing of the undersea optical fiber cable joint. The internal housing also includes a sidewall interconnecting the opposing end faces, which extends between the opposing end faces in a longitudinal direction. The sidewall includes a receptacle portion having a plurality of thru-holes each being sized to receive a passive optical component employed in an optical amplifier. The module also includes at least one circuit board on which reside electronics associated with the optical amplifier.

Abstract: A branching unit, for use in optical communication systems, has three branches A, B and C each including a connection for a power feed and several inputs/outputs for optical fibers. Optical switches are provided for selectively coupling inputs/outputs of different branches to enable a routeing of optical signals through the unit. The routeing is effected in dependence upon the way in which each of the three branch connections are provided with an electrical power feed.

Abstract: To diminish the risk of interruption of traffic in a submarine optical cable system in the region of the shore where damage is most likely to occur, the landing-stage of the system has duplicated spaced-apart cables between a submerged branching unit and an onshore submarine line terminal endstation. Various changeover modes are disclosed, including those where both cables are coupled to signals at all times and changeover is accomplished by blocking amplifiers.

Abstract: An optical submarine communication system has a land cable connected to a terminal apparatus which is installed on land near the seashore for transmitting an optical signal and electric power. The land cable is connected to an optical submarine cable through a beach manhole, and a repeater is connected to the optical submarine cable. The optical submarine communication system has a surge suppressor provided on the land cable, whereby a surge generated from the terminal apparatus side because of a lightning stroke or an insulation failure is suppressed from reaching and damaging the repeater.