Abstract: The present disclosure describes a network including two levels of switching: a first level including wavelength selective switching via a first type of switching module, and a second level including fiber level switching via a second type of switching module. The two levels of switching allow for maintaining wavelength selective switching between transmission directions while introducing fiber selective switching between network degrees of the same transmission direction. The first type of switching module is configured to transmit and receive optical signals having a first set of wavelengths at a first network degree at a first direction in a node of a network. The second type of switching module is configured to transmit and receive the optical signals from the first type of switching module and route the optical signals at the first network degree to a second network degree in a second direction.

Abstract: A system is provided along a route of a network including a first transponder at a first node and a second transponder at a second node. The system further includes one or more processors configured to detect, in a first waveform measured at the first transponder, a first signature at a first time point, and configured to detect, in a second waveform measured at the second transponder, a second signature at a second time point. The one or more processors may correlate the first waveform and the second waveform, and determine, based on the correlation, that the first signature and the second signature correspond to a same event occurring along the route of the network. Based on comparing the first time point and the second time point, the one or more processors may determine an estimated location of the event.

Abstract: Systems and methods of undersea optical communication are provided. An undersea optical amplifier assembly can include a water-tight housing and a photonic integrated circuit disposed within the housing. The photonic integrated circuit includes a plurality of optical fiber inputs, each configured to receive an end of a respective optical fiber of a first fiber optic cable bundle, and a plurality of optical fiber outputs. Each optical fiber output corresponds to a respective optical fiber input to form a fiber optic input-output pair, and is configured to receive an end of a respective optical fiber of a second fiber optic cable bundle. The photonic integrated circuit includes an optical amplifier optically coupled to each respective fiber optic input-output pair. The housing includes a first water-tight access port configured to receive the first fiber optic cable bundle, and a second water-tight access port configured to receive a second fiber optic cable bundle.

Abstract: A system is provided along a route of a network including a first transponder at a first node and a second transponder at a second node. The system further includes one or more processors configured to detect, in a first waveform measured at the first transponder, a first signature at a first time point, and configured to detect, in a second waveform measured at the second transponder, a second signature at a second time point. The one or more processors may correlate the first waveform and the second waveform, and determine, based on the correlation, that the first signature and the second signature correspond to a same event occurring along the route of the network. Based on comparing the first time point and the second time point, the one or more processors may determine an estimated location of the event.

Abstract: A network is provided with a plurality of nodes connected to one another. At least one node of the plurality of nodes include one or more transponders. For example, the transponders may be configured to receive optical signals having a first set of wavelengths at a first degree of a plurality of degrees in the at least one node. The transponders may convert the received optical signals into electrical signals, and then regenerate optical signals by generating, based on the electrical signals, optical signals having a second set of wavelengths. The node may further include one or more switches configured to route the regenerated optical signals to one or more of the plurality of degrees of the at least one node.

Abstract: Systems and methods for performing connectivity verification testing and topology discovery in a reconfigurable optical add/drop multiplexer (ROADM) are provided. The ROADM can include a ROADM block having a plurality of internal ports connected to a fiber shuffle via respective optical fibers. The ROADM block includes a test signal transmitter configured to inject an outgoing test signal having a unique signature into each internal port. The outgoing test signals are out-of-band of optical data signals traversing the ROADM. The ROADM block includes a test signal monitor configured to monitor for incoming test signals at each of the internal ports. The test signal monitor is configured to validate, based on a signature of an incoming test signal received at an internal port of the ROADM block, whether a valid connection exists between the internal port and an internal port of a second ROADM block.

Abstract: Systems and methods of undersea optical communication are provided. An undersea optical amplifier assembly can include a water-tight housing and a photonic integrated circuit disposed within the housing. The photonic integrated circuit includes a plurality of optical fiber inputs, each configured to receive an end of a respective optical fiber of a first fiber optic cable bundle, and a plurality of optical fiber outputs. Each optical fiber output corresponds to a respective optical fiber input to form a fiber optic input-output pair, and is configured to receive an end of a respective optical fiber of a second fiber optic cable bundle. The photonic integrated circuit includes an optical amplifier optically coupled to each respective fiber optic input-output pair. The housing includes a first water-tight access port configured to receive the first fiber optic cable bundle, and a second water-tight access port configured to receive a second fiber optic cable bundle.

Abstract: Systems and methods for performing connectivity verification testing and topology discovery in a reconfigurable optical add/drop multiplexer (ROADM) are provided. The ROADM can include a ROADM block having a plurality of internal ports connected to a fiber shuffle via respective optical fibers. The ROADM block includes a test signal transmitter configured to inject an outgoing test signal having a unique signature into each internal port. The outgoing test signals are out-of-band of optical data signals traversing the ROADM. The ROADM block includes a test signal monitor configured to monitor for incoming test signals at each of the internal ports. The test signal monitor is configured to validate, based on a signature of an incoming test signal received at an internal port of the ROADM block, whether a valid connection exists between the internal port and an internal port of a second ROADM block.

Abstract: Systems and methods for allocating optical circuits on optical mesh networks are disclosed herein. For example, the disclosed methods include identifying a new circuit to be added to a mesh optical network and identifying a set of potential paths for the new circuit. For each optical link in each identified potential path, costs are determined for a plurality of frequency slots of allocating the new circuit to a potential path including the optical link. The cost of allocating a given frequency slot on a given optical link is determined in part based on the lengths of optical circuits that can traverse the given optical link using that frequency slot. Total cost values are calculated for allocating available frequency slots over each of the identified potential paths, and one of the identified potential paths and one or more of the available frequency slots are allocated for the new circuit.

Abstract: Parallel optical transponders with an optical comb source, and methods of using the same, are provided. The optical comb source can provide multiple optical carriers from a single source. The multiple optical carriers can be phase-aligned, which can allow joint processing of a received signal. The multiple optical carriers can also allow for modulating a demultiplexed data signal using multiple modulators rather than modulating the entire data signal using a single modulator.

Abstract: A system for analyzing an optical transport network is provided. The system can generate a linear OSNR and an output power profile for each optical link element of an optical link based on an input power profile, amplifier characteristics, transport fiber characteristics, and a set of operating parameters. The system can generate a nonlinear OSNR for each optical link element based on the input power profile and transport fiber characteristics of each optical link element. The system can determine an expected performance metric for the optical link based on the linear OSNR, the non-linear OSNR, and a transmitter output OSNR. The system can designate the optical link as valid for use in the optical transport network if the expected performance metric is greater than or equal to a performance metric threshold.

Abstract: A system for analyzing an optical transport network is provided. The system can generate a linear OSNR and an output power profile for each optical link element of an optical link based on an input power profile, amplifier characteristics, transport fiber characteristics, and a set of operating parameters. The system can generate a nonlinear OSNR for each optical link element based on the input power profile and transport fiber characteristics of each optical link element. The system can determine an expected performance metric for the optical link based on the linear OSNR, the non-linear OSNR, and a transmitter output OSNR. The system can designate the optical link as valid for use in the optical transport network if the expected performance metric is greater than or equal to a performance metric threshold.

Abstract: Parallel optical transponders with an optical comb source, and methods of using the same, are provided. The optical comb source can provide multiple optical carriers from a single source. The multiple optical carriers can be phase-aligned, which can allow joint processing of a received signal. The multiple optical carriers can also allow for modulating a demultiplexed data signal using multiple modulators rather than modulating the entire data signal using a single modulator.

Abstract: The integrated network element offers an efficient fiber-chip coupling of multiple outputs of a polarization sensitive photonic integrated circuit (PIC) using a programmable mirror co-packaged with the PIC. Efficient fiber-chip coupling requires precise and active alignment of all free-space components. These constraints can be reduced by using a programmable mirror in the form of a liquid crystal on silicon (LCoS) device. The LCoS can be programmed with patterns that offer highly accurate beam-steering and focusing functionality. Imaging optics may be used at the PIC facet to provide some degree of collimation in the free-space optical path to efficiently illuminate the LCoS. By reprogramming the LCoS switching between two outputs/inputs can be obtained at high speed.

Abstract: The integrated network element offers an efficient fiber-chip coupling of multiple outputs of a polarization sensitive photonic integrated circuit (PIC) using a programmable mirror co-packaged with the PIC. Efficient fiber-chip coupling requires precise and active alignment of all free-space components. These constraints can be reduced by using a programmable mirror in the form of a liquid crystal on silicon (LCoS) device. The LCoS can be programmed with patterns that offer highly accurate beam-steering and focusing functionality. Imaging optics may be used at the PIC facet to provide some degree of collimation in the free-space optical path to efficiently illuminate the LCoS. By reprogramming the LCoS switching between two outputs/inputs can be obtained at high speed.