Patents by Inventor Nanshan Cao

Nanshan Cao 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: 11894966
    Abstract: The present disclosure provides a method for estimating a frequency offset, including: extracting sampling points from an input signal according to preset intervals to obtain a plurality of groups of sampling points, with the preset intervals of the groups of sampling points being different; performing processes on a current sampling point and the groups of sampling points to obtain data of arguments of complex numbers corresponding to the preset intervals; and determining an estimation value of a frequency offset of a current input signal according to the data of arguments of complex numbers corresponding to the preset intervals. The present disclosure further provides an apparatus for estimating a frequency offset, an electronic device and a computer-readable medium.
    Type: Grant
    Filed: April 2, 2021
    Date of Patent: February 6, 2024
    Assignee: SANECHIPS TECHNOLOGY CO., LTD.
    Inventors: Shuangxi Li, Yangzhong Yao, Nanshan Cao, Yunpeng Li
  • Publication number: 20230144980
    Abstract: The present disclosure provides a method for estimating a frequency offset, including: extracting sampling points from an input signal according to preset intervals to obtain a plurality of groups of sampling points, with the preset intervals of the groups of sampling points being different; performing processes on a current sampling point and the groups of sampling points to obtain data of arguments of complex numbers corresponding to the preset intervals; and determining an estimation value of a frequency offset of a current input signal according to the data of arguments of complex numbers corresponding to the preset intervals. The present disclosure further provides an apparatus for estimating a frequency offset, an electronic device and a computer-readable medium.
    Type: Application
    Filed: April 2, 2021
    Publication date: May 11, 2023
    Inventors: Shuangxi LI, Yangzhong YAO, Nanshan CAO, Yunpeng LI
  • Publication number: 20220407678
    Abstract: The present disclosure provides a signal sampling method and apparatus, and an optical receiver. The method includes sampling a burst signal that is received according to a first sampling frequency to obtain a first sampling signal; sampling a preamble signal in the first sampling signal according to a second sampling frequency to obtain a second sampling signal; determining a phase difference between the burst signal and a local sampling clock corresponding to the first sampling frequency according to the second sampling signal; and interpolating the first sampling signal according to the phase difference to obtain a target sampling signal.
    Type: Application
    Filed: September 23, 2020
    Publication date: December 22, 2022
    Inventors: Guohua GU, Yangzhong YAO, Nanshan CAO, Chungui TAO
  • Patent number: 9866240
    Abstract: An MAP algorithm-based Turbo decoding method and apparatus. The method includes: iteratively estimating an information symbol by using an MAP algorithm, acquiring an ? and ? window boundary values of each sliding window by means of window boundary value inheritance, acquiring an ? block boundary value and ? block boundary value of each sub-block by means of block boundary value inheritance, and recursively calculating posterior probability Log Likelihood Ratio (LLR) values of a whole window and a whole block according to the ? boundary values and the ? boundary values (101); and performing decoding decision according to the LLR values (102).
    Type: Grant
    Filed: September 15, 2014
    Date of Patent: January 9, 2018
    Assignee: SANECHIPS TECHNOLOGY CO., LTD.
    Inventors: Xi Wang, Ning Qiu, Nanshan Cao
  • Publication number: 20170134042
    Abstract: Disclosed is an MAP algorithm-based Turbo decoding method and apparatus. The method includes: iteratively estimating an information symbol by using an MAP algorithm, acquiring an ? and ? window boundary values of each sliding window by means of window boundary value inheritance, acquiring an ? block boundary value and ? block boundary value of each sub-block by means of block boundary value inheritance, and recursively calculating posterior probability Log Likelihood Ratio (LLR) values of a whole window and a whole block according to the ? boundary values and the ? boundary values (101); and performing decoding decision according to the LLR values (102).
    Type: Application
    Filed: September 15, 2014
    Publication date: May 11, 2017
    Inventors: Xi Wang, Ning Qiu, Nanshan Cao
  • Patent number: 8743911
    Abstract: A synchronization method is disclosed, including: obtaining a synchronization symbol position {circumflex over (d)}0 of one time slot of an initial update period; taking Ntrack frames as an update period to adjust the synchronization symbol position, and the step of adjusting the synchronization symbol position including: obtaining a synchronization symbol position {circumflex over ({circumflex over (d)}k+1=dk+Ntrack{circumflex over (T)}k of a corresponding time slot of a (k+1)th update period according to a synchronization symbol position {circumflex over (d)}k of a corresponding time slot of a kth update period and an inter-frame sampling derivation estimation value {circumflex over (T)}k of said kth update period; obtaining synchronization symbol positions of other time slots in said kth update period according to the synchronization symbol position {circumflex over (d)}k of the corresponding time slot of the kth update period and the inter-frame sampling derivation estimation value {circumflex over (T)}k
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: June 3, 2014
    Assignee: ZTE Corporation
    Inventors: Yueyi You, Qiang Li, Ning Qiu, Nanshan Cao, Tao Zhang
  • Patent number: 8677222
    Abstract: The embodiments of the invention disclose a method and a device for decoding an RS code, the method comprising: receiving bit reliability information of the RS code output by a channel, performing a hard decision on the bit reliability information to obtain a hard-decision result value sequence; determining a type of an error of the hard-decision result value sequence according to an initial check array corresponding to an encoding mode of the RS code; according to preset corresponding relationships between types of errors of the hard-decision result value sequence and error-correcting modes capable of correcting the errors, determining an error-correcting mode corresponding to the type of the error of the hard-decision result value sequence, and performing a bit error correction on the hard-decision result value sequence according to the determined error-correcting mode; outputting the hard-decision result value sequence after the bit error correction as a decoding result.
    Type: Grant
    Filed: May 4, 2010
    Date of Patent: March 18, 2014
    Assignee: ZTE Corporation
    Inventors: Yueyi You, Qiang Li, Ning Qiu, Nanshan Cao, Tao Zhang
  • Patent number: 8667378
    Abstract: Disclosed are a decoding method and device for concatenated code, for the decoding of concatenated code composed of low density parity code (LDPC) and Reed-Solomon (RS) code. The method includes carrying out LDPC soft decision iterative decoding on bit de-interleaved data flow, and carrying out check decision on LDPC codeword obtained from decoding by using a check matrix; carrying out de-byte-interleave on an information bit of the LDPC codeword obtained from decoding and converting check information of the LDPC codeword into puncturing information of RS codeword; selecting a decoding mode according to the puncturing information of the RS codeword to carry out RS decoding. By way of the solution of the present invention, the RS decoding performance can be improved without increasing the computation complexity, thus greatly improving the receiving performance of the CMMB terminal as compared to the conventional method.
    Type: Grant
    Filed: October 22, 2010
    Date of Patent: March 4, 2014
    Assignee: ZTE Corporation
    Inventors: Tao Zhang, Yueyi You, Nanshan Cao, Yangzhong Yao
  • Patent number: 8582634
    Abstract: The present invention discloses an OFDM signal demodulation method and device thereof.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: November 12, 2013
    Assignee: ZTE Corporation
    Inventors: Qiang Li, Ning Qiu, Nanshan Cao
  • Publication number: 20120284584
    Abstract: Disclosed are a decoding method and device for concatenated code, for the decoding of concatenated code composed of low density parity code (LDPC) and Reed-Solomon (RS) code. The method includes: carrying out LDPC soft decision iterative decoding on bit de-interleaved data flow, and carrying out check decision on LDPC codeword obtained from decoding by using a check matrix; carrying out de-byte-interleave on an information bit of the LDPC codeword obtained from decoding and converting check information of the LDPC codeword into puncturing information of RS codeword; selecting a decoding mode according to the puncturing information of the RS codeword to carry out RS decoding. By way of the solution of the present invention, the RS decoding performance can be improved without increasing the computation complexity, thus greatly improving the receiving performance of the CMMB terminal as compared to the conventional method.
    Type: Application
    Filed: October 22, 2010
    Publication date: November 8, 2012
    Inventors: Tao Zhang, Yueyi You, Nanshan Cao, Yangzhong Yao
  • Publication number: 20120166915
    Abstract: The embodiments of the invention disclose a method and a device for decoding an RS code, the method comprising: receiving bit reliability information of the RS code output by a channel, performing a hard decision on the bit reliability information to obtain a hard-decision result value sequence; determining a type of an error of the hard-decision result value sequence according to an initial check array corresponding to an encoding mode of the RS code; according to preset corresponding relationships between types of errors of the hard-decision result value sequence and error-correcting modes capable of correcting the errors, determining an error-correcting mode corresponding to the type of the error of the hard-decision result value sequence, and performing a bit error correction on the hard-decision result value sequence according to the determined error-correcting mode; outputting the hard-decision result value sequence after the bit error correction as a decoding result.
    Type: Application
    Filed: May 4, 2010
    Publication date: June 28, 2012
    Applicant: ZTE CORPORATION
    Inventors: Yueyi You, Qiang Li, Ning Qiu, Nanshan Cao, Tao Zhang
  • Publication number: 20120114031
    Abstract: The present invention discloses an OFDM signal demodulation method and device thereof.
    Type: Application
    Filed: April 23, 2010
    Publication date: May 10, 2012
    Applicant: ZTE CORPORATION
    Inventors: Qiang Li, Ning Qiu, Nanshan Cao
  • Publication number: 20120099608
    Abstract: A synchronization method is disclosed, including: obtaining a synchronization symbol position {circumflex over (d)}0 of one time slot of an initial update period; taking Ntrack frames as an update period to adjust the synchronization symbol position, and the step of adjusting the synchronization symbol position including: obtaining a synchronization symbol position {circumflex over ({circumflex over (d)}k+1=dk+Ntrack{circumflex over (T)}k of a corresponding time slot of a (k+1)th update period according to a synchronization symbol position {circumflex over (d)}k of a corresponding time slot of a kth update period and an inter-frame sampling derivation estimation value {circumflex over (T)}k of said kth update period; obtaining synchronization symbol positions of other time slots in said kth update period according to the synchronization symbol position {circumflex over (d)}k of the corresponding time slot of the kth update period and the inter-frame sampling derivation estimation value {circumflex over (T)}k
    Type: Application
    Filed: March 25, 2010
    Publication date: April 26, 2012
    Applicant: ZTE CORPORATION
    Inventors: Yueyi You, Qiang Li, Ning Qiu, Nanshan Cao, Tao Zhang
  • Publication number: 20110228884
    Abstract: The invention provides a method and device for filtering orthogonal frequency division multiplexing (OFDM) channel estimate result, to solve the problems in the prior art that for channel estimate result filtering the realization is complex or the performance is poor. By embodiments the following method is described: transforming time domain synchronous symbols received by the terminal equipment to frequency domain synchronous symbols; computing frequency domain impulse response sequences based on the frequency domain synchronous symbols; adjusting least mean square (LMS) adaptive filter coefficients based on the frequency domain impulse response sequences; obtaining coefficients of the data symbol channel estimate result frequency domain filter based on the coefficients obtained from said adjusting; filtering the OFDM channel estimate result by using the data symbol channel estimate result frequency domain filter. The corresponding device is disclosed by the embodiments.
    Type: Application
    Filed: September 3, 2009
    Publication date: September 22, 2011
    Applicant: ZTE Corporation
    Inventors: Ning Qiu, Qiang Li, Li Chen, Nanshan Cao, Tao Zhang, Yueyi You