Abstract: An undersea fiber optic cable routing architecture including a branching unit coupled to three trunk cables capable of switching individual fibers in each fiber pair within a cable to either of the other two cables. The branching unit comprises a plurality of optical switches and a controller for receiving remote command signals and configuring the optical switches in accordance with the remote command signals.

Abstract: An undersea fiber optic cable routing architecture including a branching unit coupled to three trunk cables capable of switching individual fibers in each fiber pair within a cable to either of the other two cables. The branching unit comprises a plurality of optical switches and a controller for receiving remote command signals and configuring the optical switches in accordance with the remote command signals.

Abstract: An undersea fiber optic cable routing architecture including a branching unit coupled to three trunk cables capable of switching individual fibers in each fiber pair within a cable to either of the other two cables. The branching unit comprises a plurality of optical switches and a controller for receiving remote command signals and configuring the optical switches in accordance with the remote command signals.

Abstract: An undersea fiber optic cable routing architecture including a branching unit coupled to three trunk cables capable of switching individual fibers in each fiber pair within a cable to either of the other two cables. The branching unit comprises a plurality of optical switches and a controller for receiving remote command signals and configuring the optical switches in accordance with the remote command signals.

Abstract: An undersea fiber optic cable routing architecture including a branching unit coupled to three trunk cables capable of switching individual fibers in each fiber pair within a cable to either of the other two cables. The branching unit comprises a plurality of optical switches and a controller for receiving remote command signals and configuring the optical switches in accordance with the remote command signals.

Abstract: A system and method consistent with the present disclosure provides for automated line monitoring system (LMS) baselining that enables capturing and updating of operational parameters specific to each repeater and associated undersea elements based on high loss loopback (HLLB) data. The captured operational parameters may then be utilized to satisfy queries targeting specific undersea elements in a Command-Response (CR) fashion. Therefore, command-response functionality may be achieved without the added cost, complexity and lifespan issues related to deploying undersea elements with on-board CR circuitry. As generally referred to herein, operational parameters include any parameter that may be derived directly or indirectly from HLLB data. Some example non-limiting examples of operational parameters include span gain loss, input power, output power, gain, and gain tilt.

Abstract: A system and method consistent with the present disclosure provides for automated line monitoring system (LMS) baselining that enables capturing and updating of operational parameters specific to each repeater and associated undersea elements based on high loss loopback (HLLB) data. The captured operational parameters may then be utilized to satisfy queries targeting specific undersea elements in a Command-Response (CR) fashion. Therefore, command-response functionality may be achieved without the added cost, complexity and lifespan issues related to deploying undersea elements with on-board CR circuitry. As generally referred to herein, operational parameters include any parameter that may be derived directly or indirectly from HLLB data. Some example non-limiting examples of operational parameters include span gain loss, input power, output power, gain, and gain tilt.

Abstract: A system and method consistent with the present disclosure provides for automated line monitoring system (LMS) baselining that enables capturing and updating of operational parameters specific to each repeater and associated undersea elements based on high loss loopback (HLLB) data. The captured operational parameters may then be utilized to satisfy queries targeting specific undersea elements in a Command-Response (CR) fashion. Therefore, command-response functionality may be achieved without the added cost, complexity and lifespan issues related to deploying undersea elements with on-board CR circuitry. As generally referred to herein, operational parameters include any parameter that may be derived directly or indirectly from HLLB data. Some example non-limiting examples of operational parameters include span gain loss, input power, output power, gain, and gain tilt.

Abstract: A system and method for transmitting a wavelength division multiplexed (WDM) signal on an optical transmission path. The system includes at least one first modulation format transmitter configured to generate an associated first modulation format signal on an associated signal wavelength using a first modulation format having a first spectral efficiency, and at least one second modulation format transmitter configured to generate an associated second modulation format signal on an associated signal wavelength using a second modulation format having a second spectral efficiency higher than the first spectral efficiency. The second modulation format signals having an optical power set nominally higher than the optical power of the first modulation format signals. The first and second modulation format signals are combined into an aggregate output signal on the optical transmission path.

Abstract: A system and method for transmitting a wavelength division multiplexed (WDM) signal on an optical transmission path. The system includes at least one first modulation format transmitter configured to generate an associated first modulation format signal on an associated signal wavelength using a first modulation format having a first spectral efficiency, and at least one second modulation format transmitter configured to generate an associated second modulation format signal on an associated signal wavelength using a second modulation format having a second spectral efficiency higher than the first spectral efficiency. The second modulation format signals having an optical power set nominally higher than the optical power of the first modulation format signals. The first and second modulation format signals are combined into an aggregate output signal on the optical transmission path.

Abstract: A system and method for fault recovery in a branched optical network. In response to a fault, power distribution in channels on recovering digital line segments is adjusted to minimize a merit function based on one or more system parameters.

Abstract: A system and method for fault recovery in a branched optical network. In response to a fault, power distribution in channels on recovering digital line segments is adjusted to minimize a merit function based on one or more system parameters.

Abstract: Fault tolerance may be achieved in a branched optical communication system such that a fault in one optical path may not affect optical signals coupled from a healthy optical path. In general, a flexible branching unit is configured, when adding and dropping channels, to select channels from a healthy path and not from the faulty path (e.g., a trunk path or a branch path) to prevent non-uniform channel loading on the trunk path after the branching unit. In this manner, a fault detected on the trunk path may not affect signals from the branch path and a fault detected on the branch path may not affect signals from the trunk path, thereby providing fault tolerance. A flexible branching unit may also be capable of adjusting the number and selection of channels that are added and dropped at the branching unit.

Abstract: Channel power management may be achieved in a branched optical communication system such that uniform loading is provided across branch channels on a branch drop path without passing information signals that are not intended for the branch terminal to the branch drop path. In general, a system and method consistent with the present disclosure reuses one or more loading signals (e.g., noise bands) from the branch add path to maintain uniform loading in the branch drop path of the same branch. The system and method thus prevents trunk channels from being dropped to a branch terminal when those trunk channels are not intended for the branch terminal.

Abstract: Fault tolerance may be achieved in a branched optical communication system such that a fault in one optical path may not affect optical signals coupled from a healthy optical path. In general, a flexible branching unit is configured, when adding and dropping channels, to select channels from a healthy path and not from the faulty path (e.g., a trunk path or a branch path) to prevent non-uniform channel loading on the trunk path after the branching unit. In this manner, a fault detected on the trunk path may not affect signals from the branch path and a fault detected on the branch path may not affect signals from the trunk path, thereby providing fault tolerance. A flexible branching unit may also be capable of adjusting the number and selection of channels that are added and dropped at the branching unit.

Abstract: Channel power management may be achieved in a branched optical communication system such that uniform loading is provided across branch channels on a branch drop path without passing information signals that are not intended for the branch terminal to the branch drop path. In general, a system and method consistent with the present disclosure reuses one or more loading signals (e.g., noise bands) from the branch add path to maintain uniform loading in the branch drop path of the same branch. The system and method thus prevents trunk channels from being dropped to a branch terminal when those trunk channels are not intended for the branch terminal.