Ciena Corporation

Nortel Networks Corporation

Northern Telecom Limited

Rockstar Consortium US LP

Ciena Luxembourg S.a.r.l.

Kim Bryon Roberts

Shahab Oveis Gharan

Maurice M O'Sullivan

Han Henry Sun

James St Harley

Kuang Tsan Wu

Leo L Strawczynski

David W Boertjes

Chandra Sekhar Bontu

Mahmoud Taherzadehboroujeni

Amir Keyvan Khandani

Mohammad Ehsan Seifi

John Duncan McNicol

Ronald Joseph Gagnon

Kieran Parsons

Michael Andrew Reimer

Gerard Leo Swinkels

David Miedema

Andrew D Shiner

David J Krause

Wolfgang W Oberhammer

Yuriy Greshishchev

Charles Laperle

Akbar Ghasemi

Naim Ben-Hamida

Roland A Smith

Richard A Habel

Michel Belanger

Qunbi Zhuge

Martin Bouchard

Ramin Babaee

William Martin Snelgrove

Malcolm Betts

Jerome Chiabaut

Hamid Ebrahimzad

Maurice Stephen O'Sullivan

Ian B Betty

Douglas McGhan

Ian Hardcastle

Kevin Stuart Farley

Michael Hubbard

Manoj Verghese

Roger Carroll

Giuseppe Bordogna

Slobodan Jovanovic

Adrien Comeau

Richard D Habel

Jianzhong Xu

Hamid R Mehrvar

Richard R Habel

Jeffrey Alan Weslowski

Paul Warren

Maurice O'sullivan

Steven James Frisken

Masoud Ebrahimi Tazeh Mahalleh

Simon P Parry

Alan Robinson

David Michael Goodman

James E Whiteaway

Donald Russell Ellis

David Wright Martin

Edgar Velez

David Damian Nicholas Bevan

Mark Edward Rollins

James A Shields

Michael Mayer

Genzao Zhang

David A Fisher

Mark Andrew Hawryluck

Bertram Leesti

David John Nicholson

Wang-Hsin Peng

Julian Fells

John E Sitch

Feng Shi

Christopher R Fludger

Paul A Smeulders

Dino B Fatica

Chuandong Li

Douglas B Cross

Ahmed M Awadalla

Terrance W Taraschuk

Gregory S Burley

Dino Cosimo DiPerna

Ruibin Jin

Riyaz R Jamal

Nazib A Moledina

Andrew Sciascia

Les C Chan

Paul Van Leeuwen

Howard J Rajala

Tim A Venus

Ian Roberts

Aleksandar Vukovic

John B Mills

James StLeger Harley

John Wolczanski

Dave Walker

Philippe Neusy

A system is configured to measure () a forward error correction (FEC) decoding property () associated with applying FEC decoding () to FEC-encoded bits or symbols at a receiver device () deployed in a communication network (). The system is configured to provide () an assessment of operating conditions of the receiver device based on the FEC decoding property. The FEC decoding property comprises, for example, a distribution of a number of iterations of a FEC decoding operation applied to a plurality of FEC blocks processed within a period of time. In some examples, the FEC decoding property comprises any one of heat, temperature, current, voltage, active clock cycles, idle clock cycles, activity of parallel engines, activity of pipeline stages, and input or output buffer fill level of the FEC decoding. The assessment is based, for example, on a comparison between the FEC decoding property and reference FEC data ().

Assessing operating conditions of a receiver in a communication network based on forward error correction decoding properties

A transmitter generates an encoded vector by encoding a data vector, the encoded vector representing payload information and parity information. The encoding is mathematically equivalent to calculating three or more forward error correction (FEC) codewords from the data vector and then calculating the encoded vector from the codewords, at least one codeword being calculated from at least one recursion of a mathematical operation, and at least one codeword comprising more than 6 terms. The transmitter transmits a signal representing the encoded vector over a communication channel. A receiver determines a vector estimate from the signal and recovers the data vector from the vector estimate by sequentially decoding the codewords, wherein at least one codeword that is decoded earlier in the decoding enhances an estimate of at least one codeword that is decoded later in the decoding.

Forward error correction coding using a tree structure

In data communications, a suitably designed contrast coding scheme, comprising a process of contrast encoding () at a transmitter end () and a process of contrast decoding () at a receiver end (), may be used to create contrast between the bit error rates 'BERs' experienced by different classes of bits. Contrast coding may be used to tune the BERs experienced by different subsets of bits, relative to each other, to better match a plurality of forward error correction 'FEC' schemes () used for transmission of information bits (), which may ultimately provide a communications system () having a higher noise tolerance, or greater data capacity, or smaller size, or lower heat.

Forward error correction with outer multi-level code and inner contrast code

A transmitter () generates () an encoded vector () by encoding () a data vector (), the encoded vector representing payload information and parity information. The encoding is mathematically equivalent to calculating three or more forward error correction (FEC) codewords from the data vector and then calculating the encoded vector from the codewords, at least one codeword being calculated from at least one recursion of a mathematical operation, and at least one codeword comprising more than 6 terms. The transmitter transmits () a signal representing the encoded vector over a communication channel. A receiver () determines () a vector estimate () from the signal and recovers () the data vector from the vector estimate by sequentially decoding () the codewords, wherein at least one codeword that is decoded earlier in the decoding enhances an estimate of at least one codeword that is decoded later in the decoding.

A receiver is configured to detect, at a communication interface, a received signal that suffers from degradations incurred over a communication channel. The receiver applies an adaptive filter to a series of received blocks of a digital representation of the received signal, thereby generating respective filtered blocks, where each received block represents 2N frequency bins, and where N is a positive integer. The receiver calculates coefficients for use by the adaptive filter on a jreceived block as a function of (i) error estimates associated with an (j&#x2212;D&#x2212;1)filtered block, where D is a positive integer representing a number of blocks, and where j is a positive integer greater than (D&#x2212;1); and (ii) an inverse of an approximate covariance matrix associated with the (j&#x2212;D&#x2212;1)received block, where the approximate covariance matrix is a diagonal matrix of size L&#xd7;L, and where L is a positive integer lower than 2N.

Approximation of recursive least squares equalization

An apparatus is configured to generate, from a stream of periodic digital samples, a first sub-stream of periodic analog samples and a second sub-stream of periodic analog samples, each sub-stream comprising substantially stable time intervals. The apparatus is further configured to generate a sign-modulated sub-stream by applying to the second sub-stream a sign modulation operation effecting a sign transition during a stable time interval of the second sub-stream. The apparatus is further configured to generate an output stream of periodic analog samples based on a sum of the first sub-stream and the sign-modulated sub-stream, wherein a period of the output stream is shorter than periods of the first and second sub-streams.

Digital-to-analog conversion with sign modulation

A receiver is configured to detect, at a communication interface, a received signal that suffers from degradations incurred over a communication channel. The receiver applies an adaptive filter to a series of received blocks of a digital representation of the received signal, thereby generating respective filtered blocks. The receiver calculates coefficients for use by the adaptive filter on an jreceived block as a function of (i) error estimates associated with an (j&#x2212;D&#x2212;1)filtered block, where D is a positive integer representing a number of blocks, and where j is a positive integer greater than (D&#x2212;1); and (ii) delay compensation terms dependent on an estimate of a difference between coefficients used by the adaptive filter on an (j&#x2212;D&#x2212;1)received block and coefficients used by the adaptive filter on an (j&#x2212;1)received block

Feedback equalization with delay compensation

A method performed at an electronic device comprises receiving information bits, a first nub, and a second nub, each nub comprising redundant values; calculating first calculated determiners from first subsets of the information bits along a first dimension; calculating first corrected determiners by applying first FEC decoding to a combination of the first calculated determiners and the first nub; correcting at least one error in the information bits using a difference between the first corrected determiners and the first calculated determiners; calculating second calculated determiners from second subsets of the information bits along a second dimension that differs from the first dimension; calculating second corrected determiners by applying second FEC decoding to a combination of the second calculated determiners and the second nub; and correcting at least one additional error in the information bits using a difference between the second corrected determiners and the second calculated determiners.

Forward error correction with compression coding

A controlled switch having N inputs and a single output (N&#x2265;2) is switchable between N states. In each state a respective one of the inputs is connected to the single output. There are N sources of sub-streams of analog samples, each sub-stream composed of pairs of adjacent analog samples. Each source is coupled to a respective one of the inputs. In operation, the controlled switch is controlled by a control signal to switch between the N states. While the controlled switch is in any one of the states, a data transition occurs between two adjacent analog samples in the sub-stream whose source is coupled to the input that is connected to the single output. The single output yields a high-bandwidth analog signal. Any pair of adjacent analog samples in any one of the sub-streams substantially determines a corresponding pair of adjacent analog samples in the high-bandwidth analog signal.

Digital-to-analog converter and generation of high-bandwidth analog signals

A receiver apparatus comprises circuitry configured for storing a first sequence of values. At the receiver apparatus, a communications signal is received which conveys a second sequence of values, the second sequence of values being related to the first sequence of values. According to some examples, the second sequence of values is identical to the first sequence of values. At the receiver apparatus, P results are calculated from a cross-correlation of the first sequence of values with at least a portion of a representation of the communications signal, where P is a positive integer. According to some examples, P&#x2265;2. An estimate of a phase offset of a continuous clock is calculated as a function of the P results. According to some examples, the function is a non-linear function. The estimate of the clock phase offset may be used to achieve clock recovery at the receiver apparatus.

Clock phase detection using interior spectral components

A system is configured to measure a forward error correction (FEC) decoding property associated with applying FEC decoding to FEC-encoded bits or symbols at a receiver device deployed in a communication network. The system is further configured to provide an assessment of operating conditions of the receiver device based on the FEC decoding property. In one example, the FEC decoding property comprises a distribution of a number of iterations of a FEC decoding operation applied to a plurality of FEC blocks processed within a period of time. In some examples, the FEC decoding property comprises any one of heat, temperature, current, voltage, active clock cycles, idle clock cycles, activity of parallel engines, activity of pipeline stages, and input or output buffer fill level of the FEC decoding. In some examples, the assessment is based on a comparison between the FEC decoding property and reference FEC data.

A transmitter generates determiners from data vectors representing payload information, each determiner representing parity information dependent on the payload information. The transmitter encodes the determiners to generate a nub vector representing compressed parity information dependent on the parity information, wherein the encoding is mathematically equivalent to calculating three or more forward error correction (FEC) codewords from the determiners and then calculating the nub vector from the codewords, at least one of the codewords being calculated from at least one recursion of a mathematical operation, and at least one of the codewords comprising more than 6 terms. The transmitter transmits signals representing the data vectors and the nub vector to a receiver, where recovery of the data vectors at the receiver involves sequential decoding of the FEC codewords, wherein at least one codeword decoded earlier in the decoding enhances an estimate of at least one codeword decoded later in the decoding.

Compression forward error correction coding using a tree structure

A receiver applies first processing to a digital representation of a received signal to generate a first processed signal having first additive noise and first linear inter-symbol interference (ISI), the first processing comprising a substantially linear operation designed to substantially minimize a sum of variances of the first additive noise and the first linear ISI. The receiver applies second processing to the first processed signal to generate a second processed signal having second additive noise and second linear ISI, the second processing comprising a substantially nonlinear operation designed (i) to make a variance of the second additive noise substantially lower than the variance of the first additive noise, and (ii) to make a sum of the variance of the second additive noise and a variance of the second linear ISI substantially lower than the sum of the variances of the first additive noise and first linear ISI.

Nonlinear digital signal processing for additive noise removal

Compression coding may be used with forward error correction (FEC) coding to provide higher information rates by reducing the proportion of redundant bits relative to information bits that are transmitted from a transmitter to a receiver. In one example, first determiners and second determiners are calculated from a set of information bits, where each first determiner is calculated from a different first subset of the information bits along a first dimension, and each second determiner is calculated from a different second subset of the information bits along a second dimension that differs from the first dimension. First and second nubs are calculated from the first and second determiners, respectively, each nub comprising a number of redundant bits that is less than the number of bits in the determiners from which the nub is calculated. The information bits and the nubs are transmitted over one or more communications channels.

An optical signal modulated with a stream of symbols comprising a sequence of training symbols is received at a receiver. First equalizer circuitry calculates and applies first coefficients to digital signals representative of the optical signal, thereby resulting in first compensated signals. Second equalizer circuitry calculates second coefficients based on a correlation between the first compensated signals and digital signals representative of the sequence of training symbols and applies the second coefficients to the first compensated signals, thereby resulting in second compensated signals. Third equalizer circuitry calculates and applies third coefficients to the second compensated signals, thereby resulting in third compensated signals. The first, second, and third coefficients compensate for impairments in the optical signal varying at respective first, second, and third rates, where the third rate is higher than the first rate and lower than the second rate.

Training-aided feedforward channel equalization

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Nepean, Canada

Kim Bryon Roberts