Google Inc.

Infinera Corporation

Rene Marcel Schmogrow

Mattia Cantono

Matthew Eldred Newland

Massimiliano Salsi

Anurag Sharma

Vinayak Dangui

Arseny Vasilyev

Rodolfo Enrique Alvizu Gomez

Christina Vlachou

Jeffrey Thomas Rahn

Chen Chen

Charles L Chen

Vijayanand Vusirikala

Valey Kamalov

Ralph Hofmeister

Jia Shern Ngai

Kevin Croussore

Philipp Claudius Schindler

Margin hedging in optical communication systems allows for overhead within the optical system. A machine learning model can be trained using the output of a physics based simulation of the optical system as well as the features of the optical system. A trained machine learning model can adjust the results of a physics based simulation of an optical network to more accurately match the adjusted simulation results to the 'true' performance of the optical network. The margins of the optical communication system can be more tailored to the true performance of a designed or planned optical system.

Enhanced uncertainty management for optical communication systems

Allocating network resources to one or more signals that are to be conveyed over the network by calculating a transport capacity for a sublink of the network based on a spectral efficiency of at least one subpath included in the sublink, and allocating the sublink to at least one signal based on the calculated transport capacity.

Spectrum-aware cross-layer optimization

An optical transport network (OTN) node including a plurality of optical circuit switches (OCSs), each OCS being a respective degree of the OTN node, at least two of the OCSs including an input port configured to be connected to a respective optical transport fiber outside of the OTN node, at least one first output port connected to a first switching layer, and at least one second output port connected to a second switching layer. The first and second switching layers have different levels of granularity, such as but not limited to a wavelength switched layer, a band switched layer or a fiber switched layer.

Network architecture with variable granularity optical routing

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.

Degree switching configuration for network architecture

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.

Transponder based active monitoring of optical networks

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.

Low signal to noise ratio submarine communication system

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.

Green regenerative energy efficient network

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.

Connectivity verification testing and topology discovery

In an asynchronous optical modulation system, a drive circuit may generate a plurality of dither tones in accordance with a predetermined dither frequency ratio. Based on the components of the dither frequency ratio, the optical modulation system may be configured to determine a feedback signal magnitude component that is independent of the delay &#x3c4; and a feedback signal sign component that is also independent of the delay &#x3c4;. A feedback signal that is independent of the delay &#x3c4; can then be reconstructed based on the feedback signal magnitude component and the feedback signal sign component.

Asynchronous bias control for an optical modulator using a multiple tone detection technique with phase correction

A system and method are disclosed to characterize and correct for the effects of IQ skew and insertion loss in a coherent optical transmitter. The coherent optical transmitter receives a digital data signal including in-phase (I) and quadrature (Q) components and generates corresponding first and second dither signals. The first dither signal may be combined with the I component and the second dither signal may be combined with the Q component to generate I and Q combined signals, which may be converted into I and Q analog waveforms. An optical signal may be generated corresponding to the I and Q analog waveforms for transmission over an optical fiber. The IQ skew and/or insertion loss for the coherent optical transmitter may then be calculated based on the optical signal using the disclosed dither tone processing techniques in order to correct IQ skew and/or insertion loss impairment.

Method and apparatus for transmitter IQ skew and insertion loss detection for coherent optical systems

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.

Physical layer routing and monitoring

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.

Parallel optical transponder enabled by optical comb sources

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.

Systems and methods of analyzing an optical transport network

A method and an apparatus for non-blocking Mach-Zehnder Modulator (MZM) arm imbalance monitoring and control through tones are disclosed herein. An optical transmitter may include an MZM to supply a first portion of light to an in-phase arm and a second portion to a quadrature arm of the MZM. The optical transmitter may apply modulator arm adjustments and dither signals to the two portions. Then, the MZM may combine the two portions into an optical output signal. The optical transmitter may tap the optical output signal to provide a first portion of the optical output signal and transmit a second portion. Also, the optical transmitter may obtain first error signals, based on the first dither signal, and second error signals, based on the second dither signal, of the first portion of the output signal. The optical transmitter may change the modulator arm adjustments based on the error signals.

Growing community of inventors

Santa Clara, CA, United States of America

Rene Marcel Schmogrow