Ciena Corporation

Equinix, Inc.

Balakrishnan Sridhar

Jun Bao

Michael Y Frankel

Michael George Taylor

Jean-Luc Archambault

Vipul Bhatnagar

Mohan Rao G Lingampalli

Manveer Singh

Iwan Kartawira

Qiang Wang

James E DeGrange, Jr

Harshad P Sardesai

Charles Haggans

Mahir A Nayfeh

Jay Simpson

Andrei Csipkes

Paul Chedore

Henry H Yaffe

Si Hyung Cho

Loren S Berg

Clark Scrandis

Prasad Dasika

Dave A Schwarten

Xiaohui Yang

Jon Tsou

Steve B Alexander

Yves Pradieu

Pradeep Swargam

An example optical switch includes a plurality of input ports and a plurality of output ports, a cross-connect fabric having one or more inputs, one or more outputs, and a device to selectively cross-connect the inputs with the outputs. The optical switch includes an integrated fast optical switch comprising a first input, a first output, and a second output, wherein the first input is connected to a first one of the outputs of the cross-connect fabric, and wherein the integrated fast optical switch has a switching time that is less than a switching time of the cross-connect fabric to switch the first input between the first output on a path to a first output port of the plurality of output ports and the second output on a path to a second output port of the plurality of output ports.

Optical switch with integrated fast protection

In an example of the disclosed techniques, a method comprising computing, by a computing system, a distribution of symbol errors in a forward error correction (FEC) frame transmitted in an optical signal. The method further includes, in response to determining that the distribution of symbol errors indicates a burst error that satisfies a threshold, adjusting, in an optical transceiver module, one or more of a pre-cursor setting, a post-cursor setting, or a signal amplitude for the optical signal.

Monitoring burst errors in forward error correction frames

An example cascaded optical switch includes: a fast optical switch and a slow optical switch both having input ports and output ports. A switching time of the slow switch is longer than a switching time of the fast optical switch. The cascaded optical switch includes a first pre-cabled optical fiber connecting an output port of the slow optical switch to an input ports of the fast optical switch, and a second pre-cabled optical fiber connecting an output ports of the fast optical switch to an input ports of the slow optical switch. The fast optical switch or the slow optical switch is configured to receive configuration data to modify a switching configuration to configure a fiber cross-connect in the optical switch fabric that includes at least one of the first pre-cabled optical fiber or the second pre-cabled optical fiber.

Cascaded optical switch

Techniques are described for providing a hybrid compensation of chromatic dispersion in optical networks to reduce power consumption by coherent receivers. In some examples, a controller may receive a chromatic dispersion value of an optical signal from a coherent receiver integrated with a receiver optical network device. The controller may compare the chromatic dispersion value with a threshold. The controller may, in response to determining that the chromatic dispersion value satisfies the threshold, perform at least one of: configure a switch connected to a dispersion compensation module (DCM) with a state to provide access to the DCM to compensate the chromatic dispersion value of the optical signal, or adjust a phase response of a filter of a coherent transmitter to compensate the chromatic dispersion value of the optical signal.

Hybrid compensation of chromatic dispersion in optical networks

An optical module includes an optical amplifier configured to amplify Wavelength Division Multiplexing (WDM) channels transmitted on a fiber; and an optical time domain reflectometer (OTDR) configured to transmit an OTDR signal on the fiber and detect a back-scattered signal based thereon to test the fiber, wherein a wavelength of the OTDR signal is one of i) between one or more wavelengths associated with the optical amplifier and one or more wavelengths associated with the WDM channels and ii) greater than the one or more wavelengths associated with the WDM channels, for in-service operation of the OTDR.

Raman amplifier system and method with integrated optical time domain reflectometer

A Raman pump system for a Raman amplifier includes a plurality of primary Raman pumps each at a corresponding wavelength; and at least one pair of redundant Raman pumps including a primary redundant Raman pump at a primary wavelength and a secondary redundant Raman pump at a secondary wavelength, wherein only one of the primary redundant Raman pump and the secondary redundant Raman pump is employed based on a zero dispersion wavelength location of a fiber over which the Raman pump system operates. The secondary wavelength can be separated from the primary wavelength by at least 2 nm or 3 nm and no more than 10 nm. The Raman pump system can provide amplification across both the C Band and the L Band.

Four-wave mixing reduction due to raman pumps in optical communication systems

An optical node supporting a modular deployment and upgrade of optical spectrum includes one or more C+L-Band amplifier modules; and a modular base module configured to interface one or more C-Band optical modems; wherein, in an initial deployment configuration, the modular base module provides channelized Amplified Spontaneous Emission (ASE) loading for select channels in the C-Band via a first ASE noise source coupled to a multiplexer for the C-Band, bulk ASE loading over the L-Band via a second ASE noise source coupled to an L-Band output, and an upgrade port for connection to an L-Band upgrade module. The L-Band upgrade module can selectively connect to the upgrade port to provide an L-Band upgrade configuration where the L-Band upgrade module and the modular base module coordinate transition of the bulk ASE loading to L-Band channelized ASE loading via a third ASE noise source.

Systems and methods for modular deployment and upgrade of multiple optical spectrum bands in optical transmission systems

Raman amplifier systems and methods with an integrated Optical Time Domain Reflectometer (OTDR) for integrated testing functionality include an amplifier system, an OTDR and telemetry subsystem, and a method of operation. The OTDR and telemetry subsystem is configured to operate in an OTDR mode when coupled to a line in port and to operate in a telemetry mode when coupled to a line out port. The OTDR and telemetry subsystem enables on-demand fiber testing while also operating as a telemetry channel that is both a redundant optical service channel (OSC) and provides a mechanism to monitor Raman gain over time. The OTDR and telemetry subsystem minimizes cost and space by sharing major optical and electrical components between the integrated OTDR and other functions on the Raman amplifier.

Exemplary embodiments of the invention are drawn to a method and apparatus for the differentiation of power and channel count changes in optically amplified links. Additionally, configuration of a corresponding optical amplifier can be based on the determination of the power and channel count changes.

Differentiation of power and channel count changes in optically amplified links

Raman amplifier gain compression systems and methods based on signal power monitoring are described which estimate distributed Raman amplifier saturation based on a total power measurement at an output of a distributed Raman amplifier and correct for any changes by adjusting the pump power. Since the power measurement, gain estimation, and the pump control and done locally at the Raman amplifier, the duration of any transients is minimized. The systems and methods quickly detect transients on a fiber link using a power monitor in the Raman amplifier, estimate the change in gain due to change in input power from distributed Raman gain, and perform a feedback loop that corrects pump power to eliminate the change in Raman gain locally.

Raman amplifier gain compression systems and methods based on signal power monitoring

An extended dynamic range optical amplifier, a method of operation, and a line amplifier configuration include an optical amplifier that can be optimized for high or low span loss conditions by switching an internal stage in or out of an internal light path within the amplifier. The extended dynamic range optical amplifier can include a low gain mode and a high gain mode with an internal switch to switch out a gain mid-stage in a low gain mode to extend the useful dynamic range of the amplifier. Further, the extended dynamic range optical amplifier can use residual pump power from an initial stage to pump the gain mid-stage in the high gain mode. Additionally, the extended dynamic range optical amplifier includes remapping of gain in the initial stage and the gain mid-stage to optimize the amplifier noise performance based on the maximum output power of the amplifier.

Extended dynamic range optical amplifier

Optical service channel (OSC) systems and methods over high loss links are described utilizing redundant telemetry channels. A first telemetry channel provides a low bandwidth communication channel used when Raman amplification is unavailable on a high loss link for supporting a subset of operations, administration, maintenance, and provisioning (OAM&P) communication. A second telemetry channel provides a high bandwidth communication channel for when Raman amplification is available to support full OAM&P communication. The first and second telemetry operate cooperatively ensuring nodal OAM&P communication over high loss links (e.g., 50 dB) regardless of operational status of Raman amplification.

Optical service channel systems and methods over high loss links

The present invention provides a wavelength-switched reconfigurable optical add-drop multiplexer (R-OADM) with wavelength broadcasting capability, such that asymmetric video signal distribution and the like can be performed without sacrificing with respect to component complexity and expense. The present invention utilizes an optical splitting and combining device with the wavelength-switched R-OADM to allow the R-OADM to support network-wide wavelength broadcasts without requiring external regeneration and extra optical transceiver equipment.

Wavelength-switched optical add-drop multiplexer with wavelength broadcasting capability

The present disclosure relates to dispersion slope compensation and dispersion map management systems and methods in an optical network utilizing a reconfigurable optical add-drop multiplexer (ROADM) with a plurality of different values of dispersion compensation modules (DCMs). The DCMs form a dispersion compensation ladder at certain intermediate nodes in the optical network to provide dispersion slope compensation and dispersion map management. The reconfigurable routing structure of the ROADM enables these intermediate nodes to route individual wavelengths to any one of the DCMs as required for the particular path of the wavelength. Advantageously, the present invention removes the requirement for banded compensation at receiver nodes and allows for dispersion map management at intermediate points along a fiber route as opposed to bulk compensation at the receiver.

Growing community of inventors

Ellicott City, MD, United States of America

Balakrishnan Sridhar