Patents by Inventor Junqiang Hu

Junqiang Hu 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: 20120257897
    Abstract: An energy efficient OFDM transceiver includes a transmitter using a decision processor to control first internal elements that can be operated in parallel and can be selectively powered off or hibernated, and a receiver using a processing decision element to control second internal elements that can be operated in parallel and can be selectively powered off or hibernated, wherein control of the first and second internal elements enables tracking status of network traffic, adjustment of OFDM bandwidth based on a traffic decision and selectively powering off or hibernating parallel ones of the first and second internal elements.
    Type: Application
    Filed: April 2, 2012
    Publication date: October 11, 2012
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junqiang Hu, Dayou Qian, Ting Wang
  • Patent number: 8260140
    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: Grant
    Filed: November 15, 2007
    Date of Patent: September 4, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Yuanqiu Luo, Jianjun Yu, Junqiang Hu, Lei Xu, Philip Nan Ji, Ting Wang, Milorad Cvijetic
  • Patent number: 8233797
    Abstract: Methods and systems for processing communication signals in an Orthogonal Frequency Division Multiple Access (OFDMA)-Passive Optical Network (PON) are disclosed. An optical carrier at a wavelength generated at an optical line terminal (OLT) may be reused by optical network units (ONUs) in the network for upstream transmission of data signals to the OLT. In addition, each ONU may perform carrier suppression to avoid broadband beating noise resulting from the simultaneous transmission of upstream data signals on the same wavelength. Further, the optical source at the OLT used to generate the optical carrier may be reused as a local oscillator for coherent detection of received upstream signals to minimize any frequency offsets.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: July 31, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Dayou Qian, Neda Cvijetic, Junqiang Hu, Ting Wang
  • Patent number: 8233809
    Abstract: A method for the polarization independent frequency domain equalization (FDE) chromatic dispersion compensation on polarization multiplexing (POLMUX) coherent systems. Operationally, time domain signals are converted to frequency domain signals such that time domain convolution can be done as simple multiplications in the frequency domain. These frequency domain signals then converted back to time domain for subsequent use. The input signal size and FFT size are advantageously designed so that the output signals can be continuous with some overlap between two successive frames.
    Type: Grant
    Filed: October 28, 2009
    Date of Patent: July 31, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Dayou Qian, Ting Wang, Kai Yang, Junqiang Hu
  • Patent number: 8213794
    Abstract: A programmable optical network architecture and associated components employing a two-level orthogonal frequency division multiplexing (OFDM)/wavelength division multiplexed (WDM) mechanisms for bandwith virtualization.
    Type: Grant
    Filed: February 12, 2009
    Date of Patent: July 3, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Wei Wei, Junqiang Hu, Lei Zong, Dayou Qian, Ting Wang
  • Patent number: 8184973
    Abstract: There is provided a method for detecting optical signals comprising employing a photo diode to both directly detect a received optical signal and convert it into an electrical signal for recovery of data bit stream information in the received optical signal, the received optical signal being derived from a separation of two polarization multiplexed optical signals that were combined before being received.
    Type: Grant
    Filed: February 13, 2009
    Date of Patent: May 22, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Dayou Qian, Lei Xu, Junqiang Hu, Ting Wang
  • Publication number: 20120114341
    Abstract: A system and method are disclosed which compensate for chromatic dispersion and polarization mode dispersion in a digital signal. The signal is adjusted for chromatic dispersion in the frequency-domain. The signal is then converted to the time-domain and at least a portion of the signal is estimated to produce channel parameters. The channel parameters are converted to the frequency domain and used to compensate for polarization mode dispersion in the signal.
    Type: Application
    Filed: November 10, 2010
    Publication date: May 10, 2012
    Applicant: NEC Laboratories America, Inc.
    Inventors: JUNQIANG HU, Ting Wang
  • Patent number: 8169683
    Abstract: An apparatus includes an optical train pulse generator for generating continuous optical pulses each having a narrow width; a clock source having a high frequency for triggering the generator and operable as a sampling clock; a digital-to-analog converter DAC for converting an input signal from a digital signal processor, the DAC responsive to the sampling clock; a data modulator responsive to an amplified output from the DAC to modulate the continuous optical pulses from the train pulse generator; and a filter for removing higher frequency harmonics from the modulated continuous optical pulses out of the data modulator.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: May 1, 2012
    Assignee: NEC Laboratories America, Inc.
    Inventors: Junqiang Hu, Yutaka Yano, Ting Wang
  • Publication number: 20120082457
    Abstract: A method for clustered polyphase filtering input data converted from an optical signal converting input data from a serial form into a parallel form, permutating data symbols from the input data to form K clusters, passing the permutated data to an adder and multiplier for each cluster; and adding output of all K multipliers together to form an output.
    Type: Application
    Filed: September 30, 2010
    Publication date: April 5, 2012
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Kai Yang, Junqiang Hu, Ting Wang
  • Patent number: 8098990
    Abstract: A network system and method include a wireless base station integrated at a central office of a service provider. The wireless base station is configured to provide portable and fixed services to customers. A passive optical network is coupled to the wireless base station at the central office to provide a link to extend an antenna for wireless operations of the wireless base station to a remote site such that a wireless signal from the wireless base station is transmitted in parallel with a passive fiber network signal through the link.
    Type: Grant
    Filed: August 1, 2007
    Date of Patent: January 17, 2012
    Assignees: NEC Laboratories America, Inc., NEC Corporation
    Inventors: Junqiang Hu, Ting Wang, Dayou Qian, Yuanqiu Luo, Yoshihiko Suemura, Makoto Shibutani
  • Publication number: 20110310998
    Abstract: A parallel phase locked loop (PLL) system includes a first chain of a plurality of pre-locking PLLs that operates from a free-run state to a locked state; and a second chain of a plurality of PLLs to work from the locked-state to recover signal output.
    Type: Application
    Filed: June 18, 2010
    Publication date: December 22, 2011
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junqiang Hu, Tyrone Kwok, Ting Wang
  • Publication number: 20110304369
    Abstract: A source synchronous signal synchronization system includes a differential signal receiver; a tunable input delay element coupled to the receiver; an input serializer/deserializer (ISerDes) coupled to the tunable input delay; an alignment unit coupled to the ISerDes; and a delay control unit coupled to the tunable input delay, the ISerDes, and the alignment unit.
    Type: Application
    Filed: June 11, 2010
    Publication date: December 15, 2011
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junqiang Hu, Tyrone Kwok, Ting Wang
  • Patent number: 8023824
    Abstract: Data is transmitted between a central office and customer premises by a wavelength division multiplex passive optical network. Two laser beams with separate wavelengths are transmitted from the central office to an optical network unit in the customer premises. Both laser beams carry downstream data. One laser beam is intensity modulated by on/off keying. The other laser beam is phase modulated by differential phase shift keying, which maintains a constant optical intensity. The first laser beam is received by a first optical receiver, which demodulates the first downstream data. The second laser beam is split in two. One laser beam is sent to a second optical receiver, which demodulates the second downstream data. The other laser beam is sent to a reflective semiconductor amplifier, which modulates the beam with upstream data and transmits the beam back to a receiver in the central optical system.
    Type: Grant
    Filed: May 5, 2008
    Date of Patent: September 20, 2011
    Assignee: NEC Laboratories America, Inc.
    Inventors: Jianjun Yu, Yuanqiu Luo, Junqiang Hu, Ting Wang
  • Patent number: 8000604
    Abstract: A passive optical network (PON) device, system and method include an optical line terminal (OLT) receiver configured to receive multiple signals at different wavelengths simultaneously and enable multiple transmitters to operate at the same time during one upstream time slot. The optical line terminal employs Orthogonal Frequency Division Multiple Access (OFDMA) to transparently support a plurality of applications and enable dynamic bandwidth allocation among these applications where the bandwidth is allocated in two dimensional frequency and time space.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: August 16, 2011
    Assignees: NEC Laboratories America, Inc., NEC Corporation
    Inventors: Dayou Qian, Junqiang Hu, Jianjun Yu, Philip Nan Ji, Lei Xu, Ting Wang, Milorad Cvijetic, Toshihiko Kusano
  • Patent number: 7978975
    Abstract: Implementations of the present principles include methods, systems and apparatuses for transmitting data through a sub-carrier multiplexing and orthogonal frequency-division multiple access passive optical network. In accordance with aspects of the present principles, a plurality of optical network units are assigned electrical carrier frequency bandwidths that are narrower than a system capacity bandwidth. Modulation of optical waves transmitted between an optical line terminal and each optical network unit is conducted on different orthogonal sub-carrier frequencies within the assigned bandwidths such that sampling of said orthogonal sub-carrier frequencies is limited to the assigned electrical carrier frequency bandwidths. The waves are thereafter received and demodulated for the extraction of data.
    Type: Grant
    Filed: August 1, 2008
    Date of Patent: July 12, 2011
    Assignee: NEC Laboratories America, Inc.
    Inventors: Dayou Qian, Junqiang Hu, Philip Nan Ji, Ting Wang
  • Publication number: 20110075242
    Abstract: An apparatus includes an optical train pulse generator for generating continuous optical pulses each having a narrow width; a clock source having a high frequency for triggering the generator and operable as a sampling clock; a digital-to-analog converter DAC for converting an input signal from a digital signal processor, the DAC responsive to the sampling clock; a data modulator responsive to an amplified output from the DAC to modulate the continuous optical pulses from the train pulse generator; and a filter for removing higher frequency harmonics from the modulated continuous optical pulses out of the data modulator.
    Type: Application
    Filed: September 29, 2009
    Publication date: March 31, 2011
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junqiang Hu, Yutaka Yano, Ting Wang
  • Publication number: 20110069954
    Abstract: There is provided an optical network apparatus having interconnected processing gigabit passive optical network G-PON blades, a protection blade, and controller blade, the regular blades and protecting blade having a higher layer processing and switching interface to a G-PON media access control MAC coupled to PHY including serializer and de-serializer modules that are connected to respective interface modules, the improvement including a protecting 1:N signal drive and a protecting N:1 signal select driver coupled between the interface module and serializer and de-serializer modules of the protecting blade, respectively, for protecting connection to the interface module of the protecting blade.
    Type: Application
    Filed: September 24, 2009
    Publication date: March 24, 2011
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junqiang Hu, Ting Wang, Dayou Qian, Philip Nan Ji
  • Publication number: 20100215368
    Abstract: Methods and systems for processing communication signals in an Orthogonal Frequency Division Multiple Access (OFDMA)-Passive Optical Network (PON) are disclosed. An optical carrier at a wavelength generated at an optical line terminal (OLT) may be reused by optical network units (ONUs) in the network for upstream transmission of data signals to the OLT. In addition, each ONU may perform carrier suppression to avoid broadband beating noise resulting from the simultaneous transmission of upstream data signals on the same wavelength. Further, the optical source at the OLT used to generate the optical carrier may be reused as a local oscillator for coherent detection of received upstream signals to minimize any frequency offsets.
    Type: Application
    Filed: August 21, 2009
    Publication date: August 26, 2010
    Applicant: NEC Laboratories America, Inc.
    Inventors: Dayou Qian, Neda Cvijetic, Junqiang Hu, Ting Wang
  • Publication number: 20100196009
    Abstract: A method for the polarization independent frequency domain equalization (FDE) chromatic dispersion compensation on polarization multiplexing (POLMUX) coherent systems. Operationally, time domain signals are converted to frequency domain signals such that time domain convolution can be done as simple multiplications in the frequency domain. These frequency domain signals then converted back to time domain for subsequent use. The input signal size and FFT size are advantageously designed so that the output signals can be continuous with some overlap between two successive frames.
    Type: Application
    Filed: October 28, 2009
    Publication date: August 5, 2010
    Applicant: NEC LABORATORIES AMERICA INC
    Inventors: Dayou Qian, Ting Wang, Kai Yang, Junqiang Hu
  • Publication number: 20100142637
    Abstract: A method by an optical OFDM receiver includes converting a received optical signal to an electrical signal, deriving a digital signal from the electrical signal, and emulating, with an iterative OFDM demodulator responsive to the digital signal, a transmitter effect in the received signal of lower peak clipping and top peak distortion and applying the transmitter effect to the received signal and a decision-made signal for estimating an error function to be applied to a demodulation of the received optical signal.
    Type: Application
    Filed: December 3, 2009
    Publication date: June 10, 2010
    Applicant: NEC LABORATORIES AMERICA, INC.
    Inventors: Junqiang Hu, Dung-Huy Han, Ting Wang