Patents by Inventor Philip Nan Ji

Philip Nan 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).

  • Publication number: 20080260383
    Abstract: A Centralized Resource Management (CRM) system that supports the sharing of all the transponders in a WXC node, i.e., any spare transponder can be reconfigured to accommodate any drop channel, regardless of wavelength or input port. Consequently, network restoration in case of network failures is supported as well as the ability to reconfigure as a result of dynamic traffic requirements in the network. CRM advantageously is applied to conventional WXC node as well as WSS-based WXC nodes in the WDM networks. Three CTM schemes which manage the transponders in the WSS-based WXC node are described along with reconfiguration algorithms for an optical switchless CRM solution.
    Type: Application
    Filed: April 20, 2007
    Publication date: October 23, 2008
    Applicant: NEC LABORATORIES AMERICA
    Inventors: Lei ZHONG, Philip Nan JI, Ting WANG, Osama MATSUDA, Milorad CVIJECTIC
  • Publication number: 20080253768
    Abstract: Optical packets are generated by generating a first optical beam with a first wavelength and a second optical beam with a second optical beam. The first optical beam is modulated with a payload signal and then filtered to reduce the bandwidth of the signal. The second optical beam is modulated with a label signal. The filtered modulated first optical beam and modulated second optical beam are combined to generate a dual-wavelength optical beam.
    Type: Application
    Filed: April 1, 2008
    Publication date: October 16, 2008
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Jianjun Yu, Philip Nan Ji, Lei Xu, Ting Wang
  • Publication number: 20080240736
    Abstract: An optical device includes an interferometer for a received optical differential phase shift keying DPSK signal, and an equalizer integrated with the interferometer in a manner for reducing from optical filtering effects an interference by signal bits of the DPSK signal with signal bits of a contiguous DPSK signal. The interferometer is a Michelson delay interferometer type, but can also be a Mach-Zehnder delay interferometer type on fiber, waveguide or other optical structure. The equalizer is a Fabry-Perot type equalizer, but can be a ring resonator type or a fiber based equalizer.
    Type: Application
    Filed: March 28, 2007
    Publication date: October 2, 2008
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Philip Nan Ji, Lei Xu, Ting Wang, Shuji Murakami, Tsutomu Tajima, Yutaka Yano
  • Publication number: 20080199189
    Abstract: A colorless optical DQPSK demodulator and system operating over multiple, equally-spaced DWDM channels with fixed optical delays—capable of demodulating DQPSK within signals within DWDM communications wave bands on ITU grids using delay interferometers having fixed free spectral range at 20 GHz or 25 GHz.
    Type: Application
    Filed: February 20, 2007
    Publication date: August 21, 2008
    Applicant: NEC AMERICA INC.
    Inventors: Lei XU, Philip Nan JI, Jianjun YU, Milorad CVIJETIC, Yutaka YANO, Tsutomu TAJIMA, Shinya NAKAMURA, Ting Wang
  • Publication number: 20080166129
    Abstract: An optical network component, architecture and method for a wavelength division multiplexed passive optical network includes a band coupler configured to demultiplex first and second wavelength division multiplexed content transmitted from an optical line terminal into a first band signal and a second band signal. An arrayed wavelength grating is configured to receive the first band signal and to further demultiplex the first band signal into different wavelengths to provide a plurality of wavelength signals. An optical splitter is configured to split the second band signal into sub-signals and multiplex the sub-signals with each of the wavelength signals such that the first and second wavelength division multiplexed content is provided on a single wavelength to a user.
    Type: Application
    Filed: November 15, 2007
    Publication date: July 10, 2008
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Yuanqiu Luo, Jianjun Yu, Junqiang Hu, Lei Xu, Philip Nan Ji, Ting Wang, Milorad Cvijetic
  • Publication number: 20080063396
    Abstract: An apparatus includes a generator for obtaining at least two lightwave carriers from a single lightwave source, at least two modulators for selectively varying the lightwave carriers according to respective data signals; and a coupler for combining the modulated lightwave carriers for optical transmission. The generator can be one of an optical carrier suppression or phase modulation. The apparatus can employ a filter for separating the lightwave carriers by a fixed wavelength spacing before selectively varying the lightwave carriers according to the respective data signals. In an exemplary embodiment of the invention, the respective data signals are two 50 Gbit/s differential quadrature phase key DQPSK signals, each 50 Gbit/s DQPSK signal including a first 25 Gbit/s data signal out of phase with a second 25 Gbit/s data signal for selectively varying a respective one of the two lightwave carriers, and the combined modulated lightwave carriers are a 100 Gbit/s DQPSK signal.
    Type: Application
    Filed: March 26, 2007
    Publication date: March 13, 2008
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Jianjun Yu, Lei Xu, Philip Nan Ji, Ting Wang
  • Patent number: 7239772
    Abstract: A flexible waveband deaggregator/aggregator design is disclosed, including an embodiment that utilizes flexible band tunable filters and an embodiment that utilizes tunable interleavers. An optical cross-connect design is also disclosed which utilizes the flexible waveband deaggregators and which can replace a core all-optical switch with a fiber interconnect matrix.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: July 3, 2007
    Assignees: NEC Laboratories America, Inc., NEC Corporation
    Inventors: Ting Wang, Philip Nan Ji, Lane Zong, Osamu Matsuda
  • Publication number: 20070116468
    Abstract: A tunable asymmetric interleaver constructed from two symmetric interleavers in series, wherein either or both of the individual symmetric interleavers exhibit a wavelength shifting ability. Advantageously, tunable asymmetric interleavers so constructed provide continuous tunable interleaving ratios from 0:100 to 50:50 to 100:0 and provide attractive upgrade paths for existing and future DWDM networks and applications.
    Type: Application
    Filed: October 18, 2006
    Publication date: May 24, 2007
    Applicant: NEC LABORATORIES AMERICA
    Inventors: Philip Nan JI, Ting WANG, Arthur DOGARIU, Lei ZHONG, Osamu MATSUDA, Yuji ABE
  • Patent number: 7099529
    Abstract: A flexible band tunable filter design is disclosed which is capable of selecting any single channel or multiple of adjacent channels in a waveband of an optical signal in an optical communication network. The flexible band tunable filter has particular application in wavelength division multiplexing communication networks.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: August 29, 2006
    Assignees: NEC Laboratories America, Inc., NEC Corporation
    Inventors: Ting Wang, Philip Nan Ji, Lane Zong, Osamu Matsuda, Kojiro Watanabe