Patents by Inventor Liangcheng Jiang

Liangcheng Jiang 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: 7376176
    Abstract: The present invention relates to a method and an apparatus for adjusting an average interval of channel estimation dynamically based on Doppler-shift. The method comprises the steps of estimating Doppler-shift by using level cross rate (LCR) according to differently moving speeds of mobile terminals, determining the optimal average interval of channel estimation based on the relationship between the existing Doppler-shift and the optimal average interval of channel estimation, dynamically adjusting the average interval of channel estimation according to the determined the optimal average interval of channel estimation to make the coherent receiver obtain the optimal estimation performance at different moving speeds.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: May 20, 2008
    Assignees: The Research Institute of Telecommunication Transmission, MII, Southeast University
    Inventors: Chunming Zhao, Zhangyong Ma, Liangcheng Jiang, Xiaohu You
  • Patent number: 7310368
    Abstract: The present invention discloses an apparatus for initial synchronization and cell search in a CDMA system based on multipath energy window. The apparatus perform initial synchronization and adjacent cell search by using multipath energy window based on the processing method of multipath energy window. The apparatus can be implemented based on a parallel correlator bank. This invention also provides the application of the apparatus to a coherent spreading receiver.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: December 18, 2007
    Assignees: The Research Institute of Telecommunication Transmission, MII, Southeast University
    Inventors: Xiaohu You, Jinghong Guo, Liangcheng Jiang, Chunming Zhao, Shixin Cheng
  • Patent number: 7308017
    Abstract: The Spread Spectrum integration coherent receiver of the invention employs a time division multiplexing correlator bank and thus obtained coherent channel evaluator as a core. The receiver can execute initial PN synchronization, RAKE diversity coherent combination, AFC and adjacent cell search and combination receipt, and soft handoff. Further, “part capture in parallel based on slide energy window” and “tracking loop based on energy window barycenter” are introduced into the receiver of the invention, thereby simplifying the structure of the RAKE receiver. The receiver is capable of overcoming multipath fading, ensuring the RAKE receipt performance.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: December 11, 2007
    Assignees: The Research Institute of Telecommunication Transmission, MII, Southeast University
    Inventors: Liangcheng Jiang, Xiaohu You, Junchao Wang, Jinghong Guo, Shixin Cheng
  • Patent number: 7095993
    Abstract: An automatic frequency correction (AFC) apparatus used for CDMA multipath fading channels comprises a frequency-offset evaluator, an automatic frequency correction loop filter and a carrier frequency adjuster. The present invention provides a “multipath energy window” designing method for the non-determinacy of multipath signals in mobile communication environment. Frequency-offset information can be extracted from the multipath energy window by a simple calculation and evaluated by a maximal SNR weight process. This invention also provides a step-variable accumulation adjusting method and greatly improves the response speed of the AFC apparatus as compared with a conventional loop filter, whereby supplies better AFC required for CDMA mobile terminals.
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: August 22, 2006
    Assignee: The MITT Research Institute of Telecommunication Transmission
    Inventors: Xiaohu You, Yan Zhang, Ling Wang, Liangcheng Jiang, Shixin Cheng
  • Publication number: 20050018641
    Abstract: The present invention relates to a method and an apparatus for adjusting an average interval of channel estimation dynamically based on Doppler-shift. The method comprises the steps of estimating Doppler-shift by using level cross rate (LCR) according to differently moving speeds of mobile terminals, determining the optimal average interval of channel estimation based on the relationship between the existing Doppler-shift and the optimal average interval of channel estimation, dynamically adjusting the average interval of channel estimation according to the determined the optimal average interval of channel estimation to make the coherent receiver obtain the optimal estimation performance at different moving speeds.
    Type: Application
    Filed: September 3, 2002
    Publication date: January 27, 2005
    Inventors: Chunming Zhao, Xhangyong Ma, Liangcheng Jiang, Xiaohu You
  • Publication number: 20040081114
    Abstract: The Spread Spectrum integration coherent receiver of the invention employs a time division multiplexing correlator bank and thus obtained coherent channel evaluator as a core. The receiver can execute initial PN synchronization, RAKE diversity coherent combination, AFC and adjacent cell search and combination receipt, and soft handoff. Further, “part capture in parallel based on slide energy window” and “tracking loop based on energy window barycenter” are introduced into the receiver of the invention, thereby simplifying the structure of the RAKE receiver. The receiver is capable of overcoming multipath fading, ensuring the RAKE receipt performance.
    Type: Application
    Filed: November 21, 2003
    Publication date: April 29, 2004
    Inventors: Liangcheng Jiang, Xiahou You, Junchao Wang, Jinghong Guo, Shixin Cheng
  • Publication number: 20040076225
    Abstract: The present invention discloses an apparatus for initial synchronization and cell search in a CDMA system based on multipath energy window. The apparatus perform initial synchronization and adjacent cell search by using multipath energy window based on the processing method of multipath energy window. The apparatus can be implemented based on a parallel correlator bank. This invention also provides the application of the apparatus to a coherent spreading receiver.
    Type: Application
    Filed: December 2, 2003
    Publication date: April 22, 2004
    Inventors: Xiaohu You, Jinghong Guo, Liangcheng Jiang, Chunming Zhao, Shixin Cheng
  • Publication number: 20040071116
    Abstract: An automatic frequency correction (AFC) apparatus used for CDMA multipath fading channels comprises a frequency-offset evaluator, an automatic frequency correction loop filter and a carrier frequency adjuster. The present invention provides a “multipath energy window” designing method for the non-determinacy of multipath signals in mobile communication environment. Frequency-offset information can be extracted from the multipath energy window by a simple calculation and evaluated by a maximal SNR weight process. This invention also provides a step-variable accumulation adjusting method and greatly improves the response speed of the AFC apparatus as compared with a conventional loop filter, whereby supplies better AFC required for CDMA mobile terminals.
    Type: Application
    Filed: September 29, 2003
    Publication date: April 15, 2004
    Inventors: Xiaohu You, Yan Zhang, Ling Wang, Liangcheng Jiang, Shixin Cheng