Pts Corporation

Altera Corporation

Adva Optical Networking Se

Adtran Networks Se

Ross Saunders

Ketan Bhalla

Rajkumar Nagarajan

Marc A Nadeau

James Moser

Sacha Corbeil

Kyle Edginton

Gamal Refai-Ahmed

Lee Shyue Choong

Andre Lortie

Jonathan L Bosloy

Reza Paiam

Hanan Anis

Mohammad Alfiad

Andrew Robinson

Ashish Duggal

Shihuan Zou

Thang Hoang

Dan Fossum

Avid Lemus

John Somerton

Scott Marshall

Vipul Rawat

Niall Robinson

Enos Avid Lemus-Tejada

Masood Ehsen Azad

The invention relates to a method and apparatus of operating a bidirectional optical transmission link. The optical transmission link includes a first and a second optical transceiver at a dedicated end of the optical transmission link and an optical path connecting the first and second optical transceiver. The optical transceivers apply the methods of converting an electrical digital transmit signal into an electrical PAM-n transmit signal, pre-emphasizing the electrical PAM-n transmit signal) by digital filtering and using the pre-emphasized electrical PAM-n signal) as modulating signal for optically modulating an optical carrier signal. The optical modulation method deployed is configured to create an optical PAM-n transmit signal with a positive or negative chirp. For initializing the optical transmission link (), an initialization process is performed in which at least one loop including the following steps is run through creating, in the first optical transceiver, an optical PAM-n training transmit signal and transmitting it to the second optical transceiver, the optical PAM-n training transmit signal being created using an electrical PAM-n training transmit signal including a binary training sequence. Initial values for filter parameters are used for pre-emphasizing the electrical PAM-n training transmit signal and an initial value is used for a chirp parameter that defines the positive or negative chirp of the optical PAM-n training transmit signal receiving, in the second optical transceiver, the optical PAM-n training transmit signal as an optical PAM-n training receive signal using direct detection. The optical PAM-n training receive signal is converted into an electrical PAM-n training receive signal. The method includes obtaining sampled values of the electrical PAM-n training receive signal (RP) by sampling this signal at predetermined points in time; and using the sampled values obtained and corresponding sampled values of an ideal electrical PAM-n transmit signal to determine operating values for the filter parameters and an operating value for the chirp parameter.

Method of operating a bidirectional optical transmission link and corresponding optical transmission link

A pluggable aggregation module adapted to be plugged into a network device of an optical network, said pluggable aggregation module comprising optical frontends configured to connect said pluggable aggregation module with a corresponding number of modules to exchange optical signals via optical fibres in legacy signal formats; and an electrical conversion circuit configured to convert the legacy signal formats to an internal signal format used by said network device.

Pluggable aggregation module for an optical network

A field reconfigurable muxponder for use in an optical transport system. The muxponder includes one or more tributary cards, where each tributary card is adapted to receive an optical data signal and conditions the optical data signal into an intermediate data signal constituted in accordance with a tributary interface format. In this way, the muxponder is able to aggregate optical data signals having different protocols and/or different data rates. The muxponder further includes a chassis that is adapted to receive a predefined number of tributary cards and outputs an optical system signal independently from the availability of the optical data signals from the tributary cards. The tributary cards and the chassis integrally form one line card.

Field reconfigurable line cards for an optical transport system

Associated with an optical transport system, a packet oriented supervisory network provides differentiated classes of service (CoS) for a plurality of WDM layer applications on diverse nodes such that as soon as a higher priority application or packet arrives, the lower priority application is affected in favor of the higher one. One or more optical control channels (OSC) are used as the physical medium for implementing the packet oriented supervisory network of the invention. This new functionality of the optical control channel (OSC) enables multiple services by allowing each application to use up to 100% of the OSC bandwidth, if no other application is using it.

Quality of service (QoS) based supervisory network for optical transport systems

A network diagnostic system is provided for an optical transport network having a plurality of network elements. The network diagnostic system includes at least one network element having a network diagnostic operation integrated therein and operable to perform the network diagnostic operation, thereby determining a network performance characteristic associated with the optical transport network; a wayside communication subsystem interconnecting the network elements residing in the optical transport network; and a network diagnostic device in data communication with the at least one network element and operable to initiate the network diagnostic operation at the network element.

Network diagnostic tool for an optical transport network

An iterative process is used to set the phase prechirp of a WDM optical transport system to a system's optimal level that maximizes the signal quality. A signal degradation factor takes into account linear and non-linear effects along the optical path and is used as a receive end feedback signal to control the phase prechirp level at the transmitter site. By using the FEC corrected errors rate as the feedback signal, optimization of signal quality is performed even when the system is running error free. By using an adaptive phase prechirp transmitter, signal degradation compensation can be also performed on a per wavelength basis to compensate for the residual dispersion slope and to allow optimization of individual channels independently of the net link dispersion value. This method provides more flexibility when using optical switching in core networks, as it allows path optimization to new physical link connectivity, without requiring any change to the optical components such that, significant signal degradation tuning range for a WDM optical transport system is provided.

Method of adaptive signal degradation compensation

An optical cross-connect switch is provided for routing optical data signals in an optical transport network. The optical cross-connect switch includes a plurality of signal splitters, where each signal splitter receives an optical multiplexed signal therein and operates to partition the optical multiplexed signal into a plurality of optical multiplexed signals; a plurality of wavelength selective devices connected to the plurality of signal splitters, such that a wavelength selective device is disposed at each output of each signal splitter and operates at different wavelengths to manipulate optical data signals embodied in the optical multiplexed signal; and a plurality of signal combiners connected to the plurality of wavelength selective devices, such that each signal combiner is adapted to receive an optical multiplexed signal via a wavelength selective device from each of the plurality of signal splitters, and operates to pass the optical multiplexed signal to an outlet port of the switch, thereby routing optical data signals amongst the outlet ports of the switch.

WDM cross-connects for core optical networks

An adaptive method is provided for applying chirp to an optical signal traversing through an optical network. The adaptive method comprises: applying chirp to an optical data signal at a transmitter in the optical network; transmitting the optical data signal through the optical network, the optical data signal having error detection data embedded therein; determining an error rate for the optical data signal at an egress point of the optical network, where the error rate is based on the error detection data embedded in the optical data signal; transmitting the error rate for the optical data signal to the transmitter; and adjusting the chirp being applied to the optical data signal at the transmitter based on the error rate for the optical data signal.

Adaptive method for chirping an optical data signal

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Ottawa, Canada

Ross Saunders