Probe card for testing in-wafer photonic integrated circuits (PICs) and method of use
Granted: September 7, 2010
Patent Number:
7792396
Method and apparatus for utilizing a probe card for testing in-wafer photonic integrated circuits (PICs) comprising a plurality of in-wafer photonic integrated circuit (PIC) die formed in the surface of a semiconductor wafer where each PIC comprises one or more electro-optic components with formed wafer-surface electrical contacts. The probe card has a probe card body with at least one row of downwardly dependent, electrically conductive contact probes. The probe body is transversely…
Adiabatic polarization converter
Granted: September 7, 2010
Patent Number:
7792403
The present invention relates to a waveguide structure, and methods for making the same. The waveguide structure has a polarization rotator for rotating the polarization of the electromagnetic signal, preferably by about ninety-degrees. In one embodiment, the polarization rotator has a midsection with a first level and a second level. The first level of the midsection has a width that decreases along the length of the first level, while the second level has a substantially constant width…
Virtual local area network configuration for multi-chassis network element
Granted: September 7, 2010
Patent Number:
7792017
A system, apparatus, and method for providing a plurality of internal VLANs within a networking element/node are described. Internal VLAN topologies are provisioned so that a particular VLAN(S) communicate traffic to corresponding applications. This segregation of internal traffic across a VLAN topology reduces the amount of interference between the traffic. Redundancy across the VLAN topology is provided so that traffic may be switched to another path in the event of a failure.
Low stress package
Granted: August 24, 2010
Patent Number:
7783142
Consistent with the present disclosure, a package is provided in which the PLC substrate, for example, is bonded to the underyling carrier though a limited contact area. The rest of the substrate is detached from the carrier so that stresses are applied to a limited portion of the PLC substrate. The PLC itself, however, is provided over that portion of the substrate that is detached from the carrier, and thus experiences reduced stress. Accordingly, high modulus adhesives, as well as…
Efficient synchronization of element management systems to network element attributes
Granted: August 24, 2010
Patent Number:
7783746
A system, apparatus and a method are described that synchronizes multiple element management systems with a network element. The synchronization between the management entities within the element is maintained by employing special attributes, such as sentry identification for managed objects and guard attributes for managed object tables. Using these attributes, resynchronization between the management systems is improved by reducing the amount of data retrieved by the systems and…
Monolithic transmitter photonic integrated circuit (TXPIC) with a transversely disposed output
Granted: August 10, 2010
Patent Number:
7773837
A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated…
Optical transmission network with asynchronous mapping and demapping and digital wrapper frame for the same
Granted: August 3, 2010
Patent Number:
7769051
An optical transmission network is inherently asynchronous due to the utilization of a variable overhead ratio (V-OHR). The network architecture makes extensive use of OEO regeneration, i.e., deals with any electronic reconditioning to correct for transmission impairments, such as, for example, FEC encoding, decoding and re-encoding, signal reshaping, retiming as well as signal regeneration. The optical transmission network includes a plesiochronous clocking system with intermediate…
Monolithic transmitter photonic integrated circuit (TxPIC) having tunable modulated sources with feedback system for source power level or wavelength tuning
Granted: July 6, 2010
Patent Number:
7751658
A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated…
Communication network with skew path monitoring and adjustment
Granted: July 6, 2010
Patent Number:
7751713
Embodiments of the present invention route a WDM signal across multiple communication paths using skew characteristics of at least some of the communication paths. The network is an optical transport network, using either circuit or packet based switching, and wavelength division multiplexed wavelengths and/or optical carrier groups (“OCGs”) over a fiber link to another node in the network. The plurality of communication paths involves different signal and path attributes such as a…
Tilted combiners/decombiners and photonic integrated circuits (PICs) employing the same
Granted: June 29, 2010
Patent Number:
7747114
A monolithic optical transmitter photonic integrated circuit (TxPIC) comprises a plurality of integrated modulated sources which, when all operated at constant current, display a power output that varies as a function of array position similar to a quadratic-shaped curve and, further, forming an array of signal channels each having a different wavelength output. An optical combiner/decombiner is integrated in the circuit and has at least one free space region with a plurality of ordered…
Forward error correction (FEC) enabled photonic integrated circuit (PICs) chips with multiple signal channels
Granted: June 8, 2010
Patent Number:
7734191
A forward error correction (FEC) communication device that includes a transmitter photonic integrated circuit (TxPIC) or a receiver photonic integrated circuit (RxPIC) and a FEC device for FEC coding at least one channel with a first error rate and at least one additional channel with a second error rate, wherein the first error rate is greater than the second error rate. The TxPIC chip is a monolithic multi-channel chip having an array of modulated sources integrated on the chip, each…
Protection switch decision architecture
Granted: May 11, 2010
Patent Number:
7716560
The present invention provides a system, apparatus and method for accurately identifying optical or digital impairments on a span using FEC errors identified at an intermediary node. This information may be provided to an end node within a network to switch to a redundant path around the impaired optical path or span therein. In one embodiment of the invention, signal degradation is identified by analyzing FEC data within a FEC decoded signal at an intermediary node. An identification of…
Polarization beam splitter-polarization rotator structure
Granted: April 20, 2010
Patent Number:
7702188
A polarization beam splitter-polarization rotator-polarization beam combiner optical structure comprising a pair of polarization rotators having a polarization beam splitter associated with the input ends of the two polarization rotators, and a polarization beam combiner associated with output ends of the two polarization rotators, and a method of purifying a light signal comprising TE and TM modes by disassociating the primary TE and TM modes from first order splitter and rotation error…
Monitoring of a laser source with front and rear output photodetectors to determine frontal laser power and power changes over laser lifetime
Granted: April 13, 2010
Patent Number:
7697580
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…
Dispersion mapping of transmitted channels in a WDM system
Granted: April 6, 2010
Patent Number:
7693365
Chromatic dispersion is determined based on the arrival times of different frames of data in a wavelength division multiplexed (WDM) system having an optical communication link. Namely, a first frame is transmitted on a first optical channel, which is supplied to the optical communication link. A second frame is then transmitted on a second optical channel and the transmission time difference between the two frames is obtained. At a receive end, the difference in arrival times of the two…
Optical transmission network with asynchronous mapping and demapping and digital wrapper frame for the same
Granted: March 23, 2010
Patent Number:
7684399
An optical transmission network is inherently asynchronous due to the utilization of a variable overhead ratio (V-OHR). The network architecture makes extensive use of OEO regeneration, i.e., deals with any electronic reconditioning to correct for transmission impairments, such as, for example, FEC encoding, decoding and re-encoding, signal reshaping, retiming as well as signal regeneration. The optical transmission network includes a plesiochronous clocking system with intermediate…
Wavelength locking and power control systems for multi-channel photonic integrated circuits (PICS)
Granted: March 16, 2010
Patent Number:
7680364
A transmissive active channel element is provided in each signal channel of a monolithic multi-channel TxPIC where each channel also includes a modulated source. The active channel element functions both as a power control element for both monitoring and regulating the output channel signal level of each signal channel and as a modulator for channel wavelength tagging or labeling to provide for wavelength locking the modulated sources. The power regulating function is also employed to…
Monolithic transmitter photonic integrated circuit (TxPIC) with a traversely disposed output
Granted: March 16, 2010
Patent Number:
7680368
A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated…
Optical transport network having a plurality of monolithic photonic integrated circuit semiconductor chips
Granted: March 2, 2010
Patent Number:
7672546
A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated…
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: December 22, 2009
Patent Number:
7636522
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…
