Controlled depolarization using chirp for mitigation of nonlinear polarization scattering
Granted: June 9, 2015
Patent Number:
9054808
A coherent optical transmitter circuit is disclosed in which controlled chirp is employed, enabling the suppression of nonlinear polarization scattering in dual polarization coherent systems, such as those which employ dual polarization-quadrature phase-shift keying (DP-QPSK). By separately chirping the modulated signals of each polarization tributary signal, the polarization state of the output DP-QPSK signal varies during a time period corresponding to a symbol bit period. Such…
Mitigating signal offsets in optical receivers
Granted: May 26, 2015
Patent Number:
9042820
An optical receiver circuit is disclosed in which a number of electrical signals are processed to extract data encoded therein. The electrical signals may be compared during the process to selectively remove one or more waveforms from one or more corresponding electrical signals. Various data signals, each including one or more waveforms, may then be processed to extract the encoded data. The optical receiver circuit reduces, or eliminates, electrical offsets which may be present in one…
Digital link viewer
Granted: May 19, 2015
Patent Number:
9037978
A system may receive a first user input that identifies an optical route in an optical network, may receive a second user input that identifies a direction with which to display the optical route, and may provide, based on the first user input and the second user input, a user interface. The user interface may display optical links associated with the optical route, and may display network entities associated with the optical route. The user interface may display a source entity, where…
Shared propagation region for an optical multiplexer or an optical demultiplexer
Granted: May 19, 2015
Patent Number:
9036957
An optical system may include an optical multiplexer or demultiplexer circuit having a slab with a propagation region. The propagation region may have a first propagation section and a second propagation section, such that a portion of the first propagation section and a portion of the second propagation section overlap each other to form a shared propagation section. The shared propagation section may include both the portion of the first propagation section and the portion of the…
Coolerless photonic integrated circuits (PICs) for WDM transmission networks and PICs operable with a floating signal channel grid changing with temperature but with fixed channel spacing in the floating grid
Granted: May 12, 2015
Patent Number:
9031412
A coolerless photonic integrated circuit (PIC), such as a semiconductor electro-absorption modulator/laser (EML) or a coolerless optical transmitter photonic integrated circuit (TxPIC), may be operated over a wide temperature range at temperatures higher then room temperature without the need for ambient cooling or hermetic packaging. Since there is large scale integration of N optical transmission signal WDM channels on a TxPIC chip, a new DWDM system approach with novel sensing schemes…
Polarization material on an optical multiplexer or an optical demultiplexer
Granted: May 5, 2015
Patent Number:
9025912
An optical device may include a substrate and an arrayed waveguide grating provided on the substrate. The arrayed waveguide grating may include a first slab or a second slab and multiple waveguides extending therebetween. The optical device may also include a layer of material provided on one of the first slab or second slab. The layer of material may have a thickness such that first light may have a first polarization is absorbed by the material and second light may have a second…
Optical amplifier controller
Granted: April 14, 2015
Patent Number:
9007682
A controller is configured to determine a first amount of current associated with a first power level. The controller is configured further to generate a digital pulse signal based on the first amount of current, where the digital pulse signal may have a second power level and an associated duty cycle. The controller is configured further to convert the digital pulse signal into a second amount of current and output the second amount of current as a pulse signal based on the duty cycle.
Digital link viewer
Granted: March 31, 2015
Patent Number:
8997001
A system may receive a first user input that identifies an optical route in an optical network, may receive a second user input that identifies a direction with which to display the optical route, and may provide, based on the first user input and the second user input, a user interface. The user interface may display optical links associated with the optical route, and may display network entities associated with the optical route. The user interface may display a source entity, where…
Frequency domain clock recovery
Granted: March 24, 2015
Patent Number:
8989593
Consistent with an aspect of the present disclosure, an optical signal carrying data or information is supplied to photodetector circuitry that generates a corresponding analog signal. The analog signal may be amplified or otherwise processed and supplied to analog-to-digital conversion (ADC) circuitry, which samples the analog signal to provide a plurality of digital signals or samples. The timing of such sampling is in accordance with a clock signal supplied to the ADC circuitry. A…
GMPLS signaling for networks having multiple multiplexing levels
Granted: March 17, 2015
Patent Number:
8982775
A method comprising the steps of receiving, with circuitry at a first node, a signal indicative of a request to set up an optical channel data unit label switched path between the first node and a second node in a network. Time slots for a plurality of types of signals to be transmitted from the first node to the second node are reserved, and a set up message is transmitted from the first node to the second node. The set up message identifies the plurality of signal types and the…
Nonlinearity compensation using pilot tones
Granted: March 3, 2015
Patent Number:
8971719
An optical system may have an optical transmitter including a digital signal processor to receive a signal channel, add data corresponding to a pilot tone, generate a digital signal associated with the signal channel and including the pilot tone, and output the digital signal. The optical system may further have a digital-to-analog converter to convert the digital signal to an analog signal, a laser to provide an optical signal, and a modulator to receive the optical signal and the…
Monitoring of a laser source with front and rear output photodetectors to determine frontal laser power and power changes over laser lifetime
Granted: March 3, 2015
Patent Number:
8971362
A power monitoring and correction to a desired power level of a laser or group of lasers utilizes two photodetectors which are employed to accurately determine the amount of output power from the front end or “customer” end of a laser or a plurality of such lasers. During power detection, which may be accomplished intermittently or continuously, the laser is modulated with a tone of low frequency modulation. One photodetector at the rear of the laser is employed to detect the DC…
Iterative forward error correction (FEC) on segmented words using a soft-metric arithmetic scheme
Granted: February 24, 2015
Patent Number:
8965776
A system is to receive a word on which to perform error correction; obtain segments, from the word, each segment including a respective subset of samples; update, on a per segment basis, the word based on extrinsic information associated with a previous word; identify sets of least reliable positions (LRPs) associated with the segments; create a subset of LRPs based on a subset of samples within the sets of LRPs; generate candidate words based on the subset of LRPs; identify errors…
Banded semiconductor optical amplifier
Granted: February 24, 2015
Patent Number:
8964284
A semiconductor optical amplifier module may include a beam splitter to split an optical signal into two polarization optical signals including a first polarization optical signal with a Transverse Magnetic (TM) polarization provided along a first path of two paths, and a second polarization optical signal with a Transverse Electric (TE) polarization provided along a second path of the two paths; a first rotator to rotate the TM polarization of the first polarization optical signal to TE…
Scattering device on an arrayed waveguide grating
Granted: February 17, 2015
Patent Number:
8958665
An optical device may include a substrate; an arrayed waveguide grating provided on the substrate and having first and second slabs; multiple first waveguides extending from the first slab, the multiple first waveguides may supply respective first optical signals to the first slab; multiple second waveguides extending from the second slab, the multiple second waveguides may supply respective second optical signals to the second slab; a third waveguide extending from the second slab, the…
Super-channel optical parameters GMPLS signaling and routing extensions systems and methods
Granted: January 27, 2015
Patent Number:
8942557
Methods and systems are disclosed including receiving, by circuitry of a node conforming to GMPLS protocol, a signal comprising at least one of an optical signal attribute indicative of parameters of a super-channel, the super-channel including a plurality of optical carriers, each of which having a corresponding one of a plurality of wavelengths and being modulated to carry a corresponding one of a plurality of data streams, the super-channel being provisioned in the optical network as…
Super optical channel transport unit signal supported by multiple wavelengths
Granted: January 13, 2015
Patent Number:
8934479
A node is configured to receive first optical channel data unit (ODU) signals; encapsulate one or more of the first ODU signals into a second ODU signal; encapsulate the second ODU signal into an optical channel transport unit (OTU) signal; and transmit the OTU signal on one or more optical channels.
Method and apparatus for transporting packets with specific traffic flows having strict packet ordering requirements over a network using multipath techniques
Granted: January 6, 2015
Patent Number:
8929366
The method that is disclosed enables specific information network traffic flows to retain packet ordering in a packet network in which multipath techniques are used. In a common network usage a plurality of traffic flows may be aggregated into a larger traffic flow. In such a situation, a finest granularity of individual traffic flow is referred to as a microflow and an aggregation of traffic flows is referred to as a traffic aggregate. The traffic aggregate may take a path from an…
Apparatus for compensating optical signal impairments
Granted: December 30, 2014
Patent Number:
8923707
Consistent with the present disclosure, a portion of light output from a laser, such as a local oscillator laser, is supplied to an optical circuit. The optical circuit may include a delay line interferometer that supplies a further optical signal that is sensed by a photodetector circuit. Alternatively, a 90 degree optical hybrid may be provided which receives two inputs whereby one input is delayed relative to the other input. The outputs of the optical hybrid are also supplied to a…
Supporting OAM on protecting connections in shared mesh protection environment
Granted: December 9, 2014
Patent Number:
8908533
A method for detecting the liveliness and synchronizing the control-plane and data-plane on protecting connections in a shared mesh network environment through methods for probing the protecting connection conditions by sending in-band messages; and synchronization of control plane and data plane by using LSP-ping messages on the protecting connections.
