Patents by Inventor David F. Welch

David F. Welch has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20110229149
    Abstract: Consistent with the present disclosure, a compact transmitter is provided that can generate optical signals having different modulation formats depending on optical link requirements. Preferably, the transmitter includes a photonic integrated circuit having multiple lasers and modulators. A control circuit adjusts the drive signals supplied to the modulators such that optical signals having a desired modulation format may be output from the modulators. Thus, for example, the transmitter may be used to output optical signals having a modulation format suitable for long haul or submarine links, as well as for links having a shorter distance.
    Type: Application
    Filed: March 22, 2010
    Publication date: September 22, 2011
    Inventors: STEPHEN G. GRUBB, David F. Welch
  • Patent number: 7885492
    Abstract: 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 on the same chip.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: February 8, 2011
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Vincent G. Dominic, Fred A. Kish, Jr., Mark J. Missey, Radhakrishnan L. Nagarajan, Atul Mathur, Frank H. Peters, Robert B. Taylor, Matthew L. Mitchell, Alan C. Nilsson, Stephen G. Grubb, Richard P. Schneider, Charles H. Joyner, Ting-Kuang Chiang, Marco E. Sosa
  • Publication number: 20110008039
    Abstract: 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 operating at a different wavelength, wherein at least one of the modulated sources is modulated with a respective FEC encoded signal. The TxPIC also includes an integrated wavelength selective combiner for combining the channels for transport over an optical link.
    Type: Application
    Filed: June 7, 2010
    Publication date: January 13, 2011
    Inventors: David F. Welch, Drew D. Perkins, Fred A. Kish, JR., Ting-Kuang Chiang
  • Patent number: 7773837
    Abstract: 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 on the same chip.
    Type: Grant
    Filed: September 29, 2008
    Date of Patent: August 10, 2010
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Vincent G. Dominic, Fred A. Kish, Jr., Mark J. Missey, Radhakrishnan L. Nagarajan, Atul Mathur, Frank H. Peters, Robert B. Taylor, Matthew L. Mitchell, Alan C. Nilsson, Stephen G. Grubb, Richard P. Schneider, Charles H. Joyner, Jonas Webjorn, Drew D. Perkins
  • Patent number: 7751658
    Abstract: 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 on the same chip.
    Type: Grant
    Filed: July 5, 2007
    Date of Patent: July 6, 2010
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Vincent G. Dominic, Fred A. Kish, Jr., Robert B. Taylor, Matthew L. Mitchell, Alan C. Nilsson, Stephen G. Grubb, Charles H. Joyner
  • Patent number: 7751713
    Abstract: 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 plurality of carrier wavelengths, optical carrier groups, physical communication paths (different nodes, different fibers along a same path, or any combination of the foregoing), or any other differentiating factors between two paths.
    Type: Grant
    Filed: July 23, 2007
    Date of Patent: July 6, 2010
    Assignee: Infinera Corporation
    Inventors: Drew D. Perkins, David F. Welch, Ting-Kuang Chiang, Charles H. Joyner, Edward E. Sprague, Parthiban Kandappan, Stephen G. Grubb, Biao Lu, Prasad Paranjape
  • Publication number: 20100166424
    Abstract: 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 and adaptive algorithms provides intelligent control of the PIC to optimize its performance and to allow optical transmitter and receiver modules in DWDM systems to operate uncooled. Moreover, the wavelength grid of the on-chip channel laser sources may thermally float within a WDM wavelength band where the individual emission wavelengths of the laser sources are not fixed to wavelength peaks along a standardized wavelength grid but rather may move about with changes in ambient temperature.
    Type: Application
    Filed: November 4, 2009
    Publication date: July 1, 2010
    Inventors: Radhakrishnan L. Nagarajan, Fred A. Kish, JR., David F. Welch, Drew D. Perkins, Masaki Kato
  • Patent number: 7734191
    Abstract: 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 operating at a different wavelength, wherein at least one of the modulated sources is modulated with a respective FEC encoded signal. The TxPIC also includes an integrated wavelength selective combiner for combining the channels for transport over an optical link.
    Type: Grant
    Filed: December 11, 2006
    Date of Patent: June 8, 2010
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Drew D. Perkins, Fred A. Kish, Jr., Ting-Kuang Chiang
  • Publication number: 20100080562
    Abstract: Consistent with the present disclosure, based on system requirements or in response to an increase in optical signal-to-noise level of an optical channel, such as a WDM channel, additional FEC bits are inserted into and replace selected data payload bits in each frame carried by the channel. The replaced data payload bits may then be transmitted in subsequent frames on the same channel. As a result, the transmitted frames have a reduced data payload rate, but a higher coding gain. Alternatively, the replaced data payload bits may be included in frames transmitted on another optical channel. In that case, the frames carried by the two channels typically have the same bit length or number of bits and may thus be compliant with the frame length requirements of G.709, for example. Preferably, the number of coding bits may be changed dynamically to obtain different coding gains.
    Type: Application
    Filed: September 29, 2008
    Publication date: April 1, 2010
    Inventors: DREW D. PERKINS, David F. Welch
  • Patent number: 7680368
    Abstract: 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 on the same chip.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: March 16, 2010
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Vincent G. Dominic, Fred A. Kish, Jr., Mark J. Missey, Radhakrishnan L. Nagarajan, Atul Mathur, Frank H. Peters, Robert B. Taylor, Matthew L. Mitchell, Alan C. Nilsson, Stephen G. Grubb, Richard P. Schneider, Charles H. Joyner, Jonas Webjorn, Drew D. Perkins
  • Patent number: 7672546
    Abstract: 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 on the same chip.
    Type: Grant
    Filed: June 22, 2007
    Date of Patent: March 2, 2010
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Vincent G. Dominic, Fred A. Kish, Jr., Mark J. Missey, Radhakrishnan L. Nagarajan, Atul Mathur, Frank H. Peters, Richard P. Schneider, Charles H. Joyner, Jonas Webjorn, Marco E. Sosa
  • Publication number: 20090324220
    Abstract: Embodiments of the present invention route a wavelength division multiplexed signal across multiple communication paths using skew characteristics of at least some of the communication paths. The network is a wavelength division multiplexed optical transport network. The plurality of communication paths involves different signal and path attributes such as a plurality of carrier wavelengths, optical carrier groups, physical communication paths (different nodes, different fibers along a same path, or any combination of the foregoing), or any other differentiating factors between two paths.
    Type: Application
    Filed: June 30, 2008
    Publication date: December 31, 2009
    Inventors: Drew D. Perkins, David F. Welch, Ting-Kuang Chiang, Charles H. Joyner, Edward E. Sprague, Parthiban Kandappan, Stephen Grubb, Prasad Paranjape
  • Patent number: 7636522
    Abstract: 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 and adaptive algorithms provides intelligent control of the PIC to optimize its performance and to allow optical transmitter and receiver modules in DWDM systems to operate uncooled. Moreover, the wavelength grid of the on-chip channel laser sources may thermally float within a WDM wavelength band where the individual emission wavelengths of the laser sources are not fixed to wavelength peaks along a standardized wavelength grid but rather may move about with changes in ambient temperature.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: December 22, 2009
    Assignee: Infinera Corporation
    Inventors: Radhakrishnan L. Nagarajan, Fred A. Kish, Jr., David F. Welch, Drew D. Perkins, Masaki Kato
  • Patent number: 7634195
    Abstract: A digital optical network (DON) is a new approach to low-cost, more compact optical transmitter modules and optical receiver modules for deployment in optical transport networks (OTNs). One important aspect of a digital optical network is the incorporation in these modules of transmitter photonic integrated circuit (TxPIC) chips and receiver photonic integrated circuit (TxPIC) chips in lieu of discrete modulated sources and detector sources with discrete multiplexers or demultiplexers.
    Type: Grant
    Filed: November 12, 2007
    Date of Patent: December 15, 2009
    Assignee: Infinera Corporation
    Inventors: Jagdeep Singh, Drew Perkins, David F. Welch, Mark Yin, Fred A. Kish, Jr., Stephen G. Grubb, Robert R. Taylor, Vincent G. Dominic, Matthew L. Mitchell, James R. Dodd, Jr.
  • Publication number: 20090202196
    Abstract: An optical transmitter comprises a monolithic transmitter photonic integrated circuit (TxPIC) chip that includes an array of modulated sources formed on the PIC chip and having different operating wavelengths approximating a standardized wavelength grid and providing signal outputs of different wavelengths. A wavelength selective combiner is formed on the PIC chip having a wavelength grid passband response approximating the wavelength grid of the standardized wavelength grid. The signal outputs of the modulated sources optically coupled to inputs of the wavelength selective combiner to produce a combined signal output from the combiner. A first wavelength tuning element coupled to each of the modulated sources and a second wavelength tuning element coupled to the wavelength selective combiner. A wavelength monitoring unit is coupled to the wavelength selective combiner to sample the combined signal output.
    Type: Application
    Filed: December 29, 2008
    Publication date: August 13, 2009
    Inventors: Fred A. Kish, JR., Charles H. Joyner, David F. Welch, Robert B. Taylor, Alan C. Nilsson
  • Patent number: 7570845
    Abstract: Electro-optic amplitude varying elements (AVEs) or electro-optic multi-function elements (MFEs) are integrated into signal channels of photonic integrated circuits (PICs) or at the output of such PICs to provide for various optical controlling and monitoring functions. In one case, such PIC signal channels may minimally include a laser source and a modulator (TxPIC) and in another case, may minimally include a photodetector to which channels, in either case, an AVE or an MFE may be added.
    Type: Grant
    Filed: September 29, 2008
    Date of Patent: August 4, 2009
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Fred A. Kish, Jr., Radhakrishnan L. Nagarajan, Alan C. Nilsson, Robert B. Taylor
  • Patent number: 7551815
    Abstract: A method is disclosed for monitoring and controlling the bit error rate (BER) in an optical communication network where an optical receiver in the optical transmission network. The method includes the steps of decombining a combined channel signal received from the network and then monitoring a real time bit error rate (BER) of a decombined channel signal. The determined BER is then communicated, such as through an optical service channel (OSC) to an optical transmitter source that is the source of origin of the channel signal. Based upon the determined BER, the chirp of a channel signal modulator at the optical transmitter source that generated the monitored channel signal is adjusted by, for example, adjusting its bias. The same channel signal received at the optical receiver can be monitored again to determine if an acceptable level for the BER has been achieved by the previous chirp adjustment.
    Type: Grant
    Filed: August 9, 2006
    Date of Patent: June 23, 2009
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Ting-Kuang Chiang, Vincent G. Dominic, Fred A. Kish, Jr., Radhakrishnan L. Nagarajan
  • Patent number: 7546001
    Abstract: Monolithic photonic integrated circuits (PICs) utilize forward error correction (FEC) joint encoder or plural encoders or a joint decoder or plural decoders.
    Type: Grant
    Filed: April 14, 2007
    Date of Patent: June 9, 2009
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Radhakrishnan L. Nagarajan, Fred A. Kish, Jr., Vincent G. Dominic, Ting-Kuang Chiang
  • Patent number: 7539365
    Abstract: Electro-optic amplitude varying elements (AVEs) or electro-optic multi-function elements (MFEs) are integrated into signal channels of photonic integrated circuits (PICs) or at the output of such PICs to provide for various optical controlling and monitoring functions. In one case, such PIC signal channels may minimally include a laser source and a modulator (TxPIC) and in another case, may minimally include a photodetector to which channels, in either case, an AVE or an MFE may be added.
    Type: Grant
    Filed: February 3, 2007
    Date of Patent: May 26, 2009
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Fred A. Kish, Jr., Radhakrishnan L. Nagarajan, Alan C. Nilsson, Robert L. Taylor
  • Patent number: 7526150
    Abstract: Electro-optic amplitude varying elements (AVEs) or electro-optic multi-function elements (MFEs) are integrated into signal channels of photonic integrated circuits (PICs) or at the output of such PICs to provide for various optical controlling and monitoring functions. In one case, such PIC signal channels may minimally include a laser source and a modulator (TxPIC) and in another case, may minimally include a photodetector to which channels, in either case, an AVE or an MFE may be added.
    Type: Grant
    Filed: November 3, 2006
    Date of Patent: April 28, 2009
    Assignee: Infinera Corporation
    Inventors: David F. Welch, Fred A. Kish, Jr., Radhakrishnan L. Nagarajan, Alan C. Nilsson, Robert B. Taylor