Patents by Inventor Philip N. Ji

Philip N. Ji 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).

  • Patent number: 8285145
    Abstract: In a dense wavelength division multiplexed optical network, an upgradeable, modular, colorless, directionless, reconfigurable add/drop multiplexer having a small form factor. By using wavelength selective switches and couplers, the above features are achieved without the need for photonic cross connects.
    Type: Grant
    Filed: March 5, 2010
    Date of Patent: October 9, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Philip N. Ji, Yoshiaki Aono, Hiromitsu Sugahara, Ting Wang
  • Publication number: 20120213517
    Abstract: Methods and systems for optical signal grooming that include providing one or more input signals, each having one or more modulated subcarriers, to a grooming processor; and grooming the input signals at a subcarrier level with the grooming processor to produce one or more output signals by arranging the modulated subcarriers in the output signals according to a grooming operation such that the modulated subcarriers are not demodulated or decoded prior to grooming.
    Type: Application
    Filed: December 6, 2011
    Publication date: August 23, 2012
    Applicants: NEC CORPORATION, NEC LABORATORIES AMERICA, INC.
    Inventors: Philip N. Ji, Dayou Qian, Ankitkumar N. Patel, Ting Wang, Yoshiaki Aono
  • Publication number: 20120213523
    Abstract: A method for optical layer traffic grooming includes receiving at least two optical input signals into respective optical receivers, each optical receiver having a photodetector for converting the respective optical input signal into a respective electrical signal; a grooming processor responsive to the electrical signals, the grooming processor being a radio frequency RF processor for processing the electrical signals at a subcarrier level to produce an RF orthogonal frequency division multiplexing signal OFDM signal; and modulating the groomed RF OFDM signal at a transmitter for conversion of the groomed RF OFDM into an optical signal.
    Type: Application
    Filed: February 22, 2012
    Publication date: August 23, 2012
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Philip N. Ji, Dayou Qian, Ankitkumar N. Patel, Ting Wang, Yoshiaki Aono
  • Publication number: 20120201541
    Abstract: There is provided a method in a wavelength convertible flexible optical wavelength-division multiplexing (WC-FWDM) network. The network has a plurality of optical nodes interconnected by a plurality of optical fibers. The network is for providing an overall spectrum divisible into a set of consecutive wavelength slots. At least one optical node has at least one wavelength converter for wavelength conversion. The method includes determining a channel route through the network commencing at a source node and ceasing at a destination node. The determined channel route is selectively tunable responsive to selected ones of a plurality of routing methods. The routing methods are so selected responsive to a routing policy having one or more objectives of minimization of channel blocking, minimization of a number of wavelength converters used in the network, and minimization of physical distance traversed by a channel, and minimization of operating wavelengths of a channel.
    Type: Application
    Filed: December 13, 2011
    Publication date: August 9, 2012
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Ankitkumar N. Patel, Philip N. Ji, Jason P. Jue
  • Publication number: 20110262143
    Abstract: ROADM node systems and methods of operation are disclosed. ROADM node systems may include transponder aggregators including transponders to add signals for switching through the ROADM node. The transponder aggregators include optical couplers constrained that are from coupling added signals on adjacent channels for simultaneous use. The ROADM system may include an optical interleaver that can provide an additional filtering function for the coupled signals prior to transmission of the signals on a WDM network.
    Type: Application
    Filed: June 14, 2010
    Publication date: October 27, 2011
    Applicant: NEC Laboratories America, Inc.
    Inventors: Philip N. JI, Yoshiaki AONO, Ting WANG
  • Publication number: 20110249969
    Abstract: An optical receiver system is disclosed. The system includes a local oscillator, a mixer and a processor. The local oscillator is configured to generate a laser signal to indicate a selection of one of a plurality of channels. In addition, the mixer is configured to receive signals on the plurality of channels and to utilize the laser signal to distinguish the signal on the selected channel. Further, the processor is configured to maximize a power level difference between the laser signal and at least one of the plurality of channels based on a total number of the plurality of channels by adjusting the power of the laser signal input to the mixer to limit a noise penalty in the receiver system.
    Type: Application
    Filed: April 1, 2011
    Publication date: October 13, 2011
    Applicants: NEC Laboratories America, Inc.
    Inventors: Philip N. Ji, Yoshiaki Aono, Kouichi Suzuki, Ezra Ip, Ting Wang
  • Publication number: 20110085803
    Abstract: ROADM node systems and methods of operation are disclosed. ROADM node systems may include transponder aggregators including transponders to add signals for switching through the ROADM node. The transponder aggregators may be constrained from adding signals on adjacent channels for simultaneous use. Further, the transponder aggregators may include an optical coupler in lieu of an optical multiplexer. The ROADM system may include a set of wavelength selective switches associated with output ports that can provide an additional filtering function for the added signals prior to transmission on a WDM network.
    Type: Application
    Filed: June 14, 2010
    Publication date: April 14, 2011
    Applicant: NEC Laboratories America, Inc.
    Inventors: PHILIP N. JI, Yoshiaki Aono, Ting Wang
  • Publication number: 20110052201
    Abstract: In a dense wavelength division multiplexed optical network, an upgradeable, modular, colorless, directionless, reconfigurable add/drop multiplexer having a small form factor. By using wavelength selective switches and couplers, the above features are achieved without the need for photonic cross connects.
    Type: Application
    Filed: March 5, 2010
    Publication date: March 3, 2011
    Applicant: NEC Laboratories America, Inc.
    Inventors: Philip N. Ji, Yoshiaki Aono, Hiromitsu Sugahara, Ting Wang
  • Publication number: 20100122003
    Abstract: A communication system management interface includes a control master; and one or more slaves under management by the control master; wherein each device, either the control master or slave, has at least an input signal connected to an output signal of another device to form a daisy-chain.
    Type: Application
    Filed: August 28, 2009
    Publication date: May 13, 2010
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junquiang Hu, Ting Wang, Philip N. Ji