Menara Networks, Inc.

Nortel Networks Corporation

Other

Northern Telecom Limited

Siraj Nour Elahmadi

Salam Elahmadi

Gabriel E Cardona

Adam R Hotchkiss

Kesavamurthy Nagaraj

Paul Arthur Bullock

Qingzhong Cai

Fredrick Muya

Qing Feng Zhang

Nigel Baker

Ming Ding

Shahid Akhtar

Thomas P Flanagan

George H Buabbud

Paul Tuok

Barry Coles

An optical transceiver configured to operate in a host device includes an electrical interface communicatively coupled to the host device to interface electrically with the host device, wherein the optical transceiver is compliant with a Multi-Source Agreement (MSA) which is supported by the host device; optical transceiver components communicatively coupled to the electrical interface, wherein the optical transceiver components are configured to optically interface signals with a second optical transceiver to form an optical link; and electronic dispersion compensation circuitry communicatively coupled to the optical transceiver components and configured to electronically compensate for optical fiber chromatic and/or polarization mode dispersion associated with the optical link, separate and independent from the host device.

High-speed pluggable optical transceivers with advanced functionality

An apparatus adapted to operate a pluggable optical transceiver in a plurality of modulation schemes includes core circuitry adapted to interface with a host device, wherein the host device is adapted to support the pluggable optical transceiver; direct detection modulation circuitry communicatively coupled to the core circuitry; coherent modulation circuitry communicatively coupled to the core circuitry; and selection circuitry adapted to operate one of the direct detection modulation circuitry and the coherent modulation circuitry based on a selection depending on an application of the pluggable optical transceiver.

Coherent and pulse amplitude modulation in a pluggable optical transceiver

Integrated performance monitoring (PM); optical layer operations, administration, maintenance, and provisioning (OAM&P); alarming; amplification, and the like is described in optical transceivers, such as multi-source agreement (MSA)-defined modules. A pluggable optical transceiver defined by an MSA agreement can include advanced integrated functions for carrier-grade operation which preserves the existing MSA specifications allowing the pluggable optical transceiver to operate with any compliant MSA host device with advanced features and functionality, such as Forward Error Correction (FEC), framing, and OAM&P directly on the pluggable optical transceiver. The advanced integrated can be implemented by the pluggable optical transceiver separate and independent from the host device.

Systems and methods for conveying wavelength tuning information from a pluggable optical transceiver to a host device determining the wavelength tuning information of the pluggable optical transceiver operating in the host device; appending the wavelength tuning information as part of existing data communicated between the pluggable optical transceiver and the host device; and providing the existing data with the wavelength tuning information incorporated therewith to the host device.

Pluggable optical transceiver providing wavelength tuning information

Integrated performance monitoring (PM); optical layer operations, administration, maintenance, and provisioning (OAM&P); alarming; amplification, or the like is described in optical transceivers, such as multi-source agreement (MSA)-defined modules. An optical transceiver defined by an MSA agreement can include advanced integrated functions for carrier-grade operation which preserves the existing MSA specifications allowing the optical transceiver to operate with any compliant MSA host device with advanced features and functionality. An XFP module can include integrated circuitry configured to provide forward error correction encoding and decoding; a transmitter communicatively coupled to the integrated circuit; a receiver communicatively coupled to the integrated circuit; and a module housing in which the integrated circuitry, the transmitter, and the receiver are disposed, wherein the module housing is pluggable in a host device configured to operate the pluggable optical transceiver, and wherein the forward error correction encoding and decoding is performed transparently to the host device.

Extended reach XFP transceiver with integrated forward error correction

Systems and methods for frequency-domain compensation in optical communication systems. In pre-equalization embodiments, the transmitter transforms the data stream into a frequency domain signal and applies a compensation filter before transforming it back into a pre-distorted time domain signal. As the pre-distorted time domain signal propagates through the optical channel, optical dispersion effects counter the pre-distortion, producing an equalized signal at the channel output. In post-equalization embodiments, the receiver transforms the received signal into a frequency domain signal and applies a compensation filter before transforming it back into an equalized time domain signal. Pre-equalization may prove less expensive due to the square-law characteristic of photodetectors employed by most receivers.

Frequency-domain equalization of the fiber optic channel

Embodiments of fiber optic communication systems are disclosed. In one embodiment, the system includes an optical channel having a channel response, a pulse-shaping transmitter coupled to a first end of the optical channel, and a receiver coupled to a second end of the optical channel. The transmitter includes a spread pulse modulator to shape pulses of data prior to transmission and an electrical to optical converter to transmit electrical data signals as the light signals over the optical channel. The receiver includes an optical to electrical converter to receive light signals from the optical channel and generate electrical data signals and a matched filter to receive and filter the electrical data signals with a response substantially matching a combined response of the transmitter and the channel response to increase a signal to noise ratio thereof.

Systems with spread-pulse modulation and nonlinear time domain equalization for fiber optic communication channels

Methods, apparatus, and systems for an optical communication channel. A data signal is preconditioned prior to transmission over a fiber optic cable to minimize signal distortion and transmitted over a fiber optic cable. Preconditioning may include none, one or more, or all of the following: encoding the data signal using a run length limited code, correlating bits of the data signal, and spreading out the pulses in the time-domain in the data signal. The pulse spreading function can be implemented either in the electrical domain prior to the electrical-to-optical conversion; in the optical domain during and/or after the electrical-to-optical conversion; or a combination of both. During reception, the data signal and clock are recovered. Recovery may include maintaining an amplitude in an electrical signal, filtering the electrical signal, shaping the electrical signal, and removing distortions and intersymbol interference (ISI) from the received electrical signal.

Methods of spread-pulse modulation and nonlinear time domain equalization for fiber optic communication channels

A transmitter and transceiver for an optical communication channel may include a data encoder, a partial response (PR) precoder, a pulse filter, and an electrical-to-optical converter to transmit a spread pulse signal over an optical communication channel. The data encoder to encode the transmit data into coded data. The precoder to correlate bits of the coded data together into a precoded signal at the output of the precoder. The pulse filter to spread out the pulses in the precoded signal into a spread-pulse signal at the output of the pulse-shaping filter. The electrical-to-optical converter to convert an electrical spread-pulse signal into light pulses at its optical output. A transceiver may further include an optical-to-electrical converter, an automatic gain controller, a matched filter, a PR finite impulse response equalizing filter, a maximum likelihood sequence estimation detector, and a data decoder in order to decode and recover the data.

Apparatus with spread-pulse modulation and nonlinear time domain equalization for fiber optic communication channels

A system and method for transmitting and restoring an optical signal in an optical ring is presented. The optical ring comprises a plurality of nodes, each node containing an optical cross connect switching fabric coupled to a data switch. The optical cross connect switching fabric and the data switch are coupled to a short reach side of a wavelength translation device. A long reach side of the wavelength translation device is coupled to a dense wave division multiplex (DWDM) coupler. The optical cross connect switching fabric and the data switch include a protect channel and a working channel for transporting the optical signal. The wavelength translation device receives the optical signal at a high speed rate, where the optical signal is a short reach optical signal and originates from a high speed interface on the data switch. The wavelength translation device then maps the short reach optical signal into a long reach DWDM optical signal at the high speed rate and forwards, via the DWDM coupler, the long reach optical signal to an adjacent DWDM coupler located at an adjacent node. If a link failure occurs and has not recovered, and the protect channel is not available, optical cross connect switching fabrics at adjacent nodes on each side of the failed link switch the optical signal to an alternate diverse protect port. An optical pass through of the switched optical signal between any transit nodes in the optical ring is then configured resulting in a restoration path for the working channel.

System and method for transmitting and restoring an optical signal

A system and method for connecting traffic along a communications network is accomplished by rerouting traffic upon the detection of a fault condition along a primary connection path. Signals are divided into different wavelength regions labeled red and blue, respectively. The wavelength bands between transmit and receive channels are alternated between red and blue band regions and then combined, multiplexed or &ldquo;bundled&rdquo; together by a wideband wavelength division multiplexer in a single non wavelength specific transmission medium for connection to a single uni-directional Optical Cross Connect System (OCCS) port. Additionally, the receiving end of a single medium is connected to a wavelength division multiplexer which unbundles the combined red and blue band signals upon reception.

Apparatus and method for restoring fiber optic communications network connections

A system and method for connecting traffic along a communications network is accomplished by rerouting traffic upon the detection of a fault condition along a primary connection path. A laser-diode transmitter, uniquely tagged, transmits a specific bit pattern signature header unique to the transmitter at the beginning of a predetermined transmission sequence. The network recognizes the unique identifier and configures the network to route all traffic from the identified transmitter along a specific path to its intended destination.

Apparatus and method for self routing control mechanism for restoring fiber optic communications network connections

An optical communications network configured in a shared protect capacity architecture. The network includes a plurality of shared and unshared nodes; a plurality of working lines connecting the plurality of nodes to form a ring that shares two or more nodes with another ring; a shared protect fiber optic line connecting the two shared nodes; and a plurality of protect lines connecting the plurality of unshared nodes which are connected by the plurality of working lines. By optically coupling a first Add-Drop Multiplexer of a first shared node to a first port of an optical cross connect using a first connecting path; optically coupling a second Add-Drop Multiplexer of the first shared node to a second port of the optical cross connect using a second connecting path; and optically coupling a third port of the Optical Cross Connect to a second shared node through a shared protect path, both rings may use the shared protect path to re-route traffic therethrough in the event that one of the rings has a break which severs the working and protect lines which couple two of the nodes thereof. The reduction in the quantity of protect lines, hence the fiber, and the equipment resulting in the associated cost savings are transparent to bit or baud rate, type of optical fiber, and signal format.

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Dallas, TX, United States of America

Siraj Nour Elahmadi