Nortel Networks Corporation

Altera Corporation

Pts Corporation

Marc A Nadeau

James Moser

Ross Saunders

Kyle Edginton

Ketan Bhalla

Gamal Refai-Ahmed

Andre Lortie

Lee Shyue Choong

Ping Wai Wan

Matthew D Brown

Michel Pigeon

Chung Y Wu

Ashley A Truscott

Collin G Kelly

Ronald D Hoffe

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

A system for recovering a clock signal from a data signal is described. The system uses an oscillator adapted to generate an oscillator output signal, a first detecting circuit for obtaining a coarse frequency-lock condition between the data signal and a recovered clock signal, a second detecting circuit for obtaining a phase-locked condition between the data signal and the recovered clock signal, a lock-detecting circuit responsive to the first detecting circuit for detecting an out-of-lock condition between the data signal and the recovered clock signal, and a control circuit responsive to the lock-detecting circuits and adapted to control the oscillator to generate an oscillator output signal on the basis of the first detecting circuit during an out-of-lock condition, and otherwise to generate the oscillator output signal on the basis of the second detecting circuit. The advantages include a much wider pull-in range for frequency acquisition, and an accurate and robust measure of a quality of received data.

Method and apparatus for clock recovery and data qualification

The present invention comprises an operational algorithm, and calibration process, for an avalanche photodiode (ADP) receiver which takes into account an APD behavioral model. In-situ optical and electrical measurements (calibration) of the APD are performed to determine key constants for use in the model. Knowledge of these constants allows for optimum operation of the APD over a wide range of input optical power. The operational algorithm also gives an estimate of input optical power over a wide range of ambient temperatures.

Method for calibrating and operating an uncooled avalanche photodiode optical receiver

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Kanata, Canada

Marc A Nadeau