Patents by Inventor Xiaojian DONG

Xiaojian DONG 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: 9853808
    Abstract: An initial cell searching method includes: receiving at least one frame data sequence including synchronization channel signals; performing a correlation process between all synchronization sequences stored in user equipment and the received at least one data sequence to obtain correlation sequences, and calculating correlation power sequences corresponding to each of the correlation sequences; searching a highest peak and a secondary peak for each of the correlation power sequences, and recording the highest peak and corresponding position and the secondary peak and corresponding position; and determining a target cell ID based on a first target sequence.
    Type: Grant
    Filed: November 21, 2013
    Date of Patent: December 26, 2017
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Yongfang Zhou, Fajun Yan, Xiaojian Dong
  • Patent number: 9749154
    Abstract: The method includes receiving communication signals in a time domain and to aa frequency domain, providing resource blocks in the frequency domain including a first and second resource block, selecting first pilot signals from first resource block and second pilot signals from second resource block, calculating a first average value based on the first pilot signals, calculating a second average value, determining a phase difference between the first and second pilot signals using the first and second average values, adjusting a first phase of first resource block using the phase difference, providing a first waveform using the first resource block with adjusted the first phase and the second resource block, applying a smoothing filter against the first waveform to generate a second waveform, generating a third waveform using at least the first and third set of phase and amplitude differences, and converting third waveform from frequency domain to time domain.
    Type: Grant
    Filed: June 20, 2013
    Date of Patent: August 29, 2017
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Qiang Cao, Xiaojian Dong
  • Patent number: 9713198
    Abstract: A mobile communication method based on a mobile communication terminal is provided, wherein a communication unit of the mobile communication terminal is adapted to working in at least two communication modes, and an antenna assembly of the mobile communication terminal is adapted to selectively working in different communication modes or in a combination of different communication modes. The method includes: selecting, based on a communication mode and a service type of the mobile communication terminal, a coupling relationship between the antenna assembly and the communication unit, so that the mobile communication terminal can work in various working modes; and if the communication mode and/or the service type of the mobile communication terminal changes, adjusting the coupling relationship between the antenna assembly and the communication unit based on the change. The mobile communication terminal using the method has characteristics of small size, low cost and less difficulty to design.
    Type: Grant
    Filed: August 6, 2014
    Date of Patent: July 18, 2017
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xiaojian Dong, Qiang Cao, Dian Xu, Baikui Xu, Yu Dong, Xuqiang Shen
  • Publication number: 20160277176
    Abstract: An initial cell searching method is provided.
    Type: Application
    Filed: November 21, 2013
    Publication date: September 22, 2016
    Applicant: Spreadtrum Communications (Shanghai) Co., Ltd.
    Inventors: Yongfang Zhou, Fajun Yan, Xiaojian Dong
  • Patent number: 9306773
    Abstract: A method of processing communication signals, is described. The method includes receiving a communication signal in a time domain, converting the communication signal to a frequency domain, providing resource blocks, the resource blocks including a first resource block and a second resource block, the first resource block having a first boundary and a second boundary, the first boundary being adjacent to the second resource block, the second boundary being non-adjacent to other resource blocks, the first resource block including pilot signals, generating a third resource block based on the one or more pilot signals, providing a first waveform based on the resource blocks and the third resource block, applying a smoothing filter against the first waveform to generate a second waveform, and converting the second waveform from the frequency domain to the time domain.
    Type: Grant
    Filed: April 28, 2013
    Date of Patent: April 5, 2016
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Qiang Cao, Xiaojian Dong
  • Patent number: 9300374
    Abstract: Methods and communication terminals for determining rank indication in a multicarrier communication system, wherein communication in the multicarrier communication system is carried out over a plurality of subcarriers, wherein the communication terminal communicates with an interface station within a cell in a multiple-input-multiple-output (MIMO) configuration. In particular, multicarrier symbols are received including pilot signals from the interface station, wherein the pilot signals contain pilot data, and channel properties are estimated based on the received multicarrier symbols, wherein the channel properties include channel properties of at least one subcarrier carrying one of the pilot signals. The pilot data are equalized based on the channel properties for determination of at least one pilot power and at least one interference power based on the equalized pilot data, and a rank indication is determined based on the at least one pilot power and the at least one interference power.
    Type: Grant
    Filed: December 19, 2012
    Date of Patent: March 29, 2016
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Xiaojian Dong
  • Patent number: 9270350
    Abstract: An OFDM communication system, a method and a device for transceiving signal are provided. The method includes: dividing M transmitting antennas into one or more groups to form U transmitting ports, wherein transmitting antennas in different groups are uncorrelated, and M is greater than or equal to U; forming P data flows using a Multiple-Input Multiple-Output (MIMO) mode, wherein P=U/2, and P is less than or equal to a number of receiving ports; and mapping a group of 2P modulation symbols, including two modulation symbols of each data flow, to a resource element pair to form Space Frequency Block Code (SFBC) coding relationships with each other, and transmitting the group of 2P modulation symbols on the U transmitting ports. The data transmission performance can be improved.
    Type: Grant
    Filed: December 31, 2013
    Date of Patent: February 23, 2016
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Yongfang Zhou, Fajun Yan, Xiaojian Dong
  • Patent number: 9264189
    Abstract: A method and device for detecting DCI are provided. The method includes: obtaining intermediate data in DCI blind detection, the intermediate data including descrambled data, decoded data and detected RNTI values; determining data to be processed from the decoded data based on a matching result of the detected RNTI values and configured RNTI values; performing encoding, rate matching and modulation on the data to be processed to obtain modulated data; calculating confidence levels of the configured RNTI values based on the modulated data and the descrambled data; and when a maximum confidence level of the configured RNTI value is greater than a predetermined threshold of confidence level, determining that the data to be processed contains detected DCI. The probability of DCI misdetection may be reduced, and further the accuracy of uplink and downlink data on a mobile terminal and system stability may be ensured.
    Type: Grant
    Filed: July 23, 2014
    Date of Patent: February 16, 2016
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Xiaojian Dong
  • Publication number: 20160043882
    Abstract: The method includes receiving communication signals in a time domain and to a frequency domain, providing resource blocks in the frequency domain including a first and second resource block, selecting first pilot signals from first resource block and second pilot signals from second resource block, calculating a first average value based on the first pilot signals, calculating a second average value, determining a phase difference between the first and second pilot signals using the first and second average values, adjusting a first phase of first resource block using the phase difference, providing a first waveform using the first resource block with adjusted the first phase and the second resource block, applying a smoothing filter against the first waveform to generate a second waveform, generating a third waveform using at least the first and third set of phase and amplitude differences, and converting third waveform from frequency domain to time domain.
    Type: Application
    Filed: June 20, 2013
    Publication date: February 11, 2016
    Applicant: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Qiang Cao, Xiaojian Dong
  • Publication number: 20160028453
    Abstract: An OFDM communication system, a method and a device for transceiving signal are provided. The method includes: dividing M transmitting antennas into one or more groups to form U transmitting ports, wherein transmitting antennas in different groups are uncorrelated, and M is greater than or equal to U; forming P data flows using a Multiple-Input Multiple-Output (MIMO) mode, wherein P=U/2, and P is less than or equal to a number of receiving ports; and mapping a group of 2P modulation symbols, including two modulation symbols of each data flow, to a resource element pair to form Space Frequency Block Code (SFBC) coding relationships with each other, and transmitting the group of 2P modulation symbols on the U transmitting ports. The data transmission performance can be improved.
    Type: Application
    Filed: December 31, 2013
    Publication date: January 28, 2016
    Applicant: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Yongfang Zhou, Fajun Yan, Xiaojian Dong
  • Publication number: 20150319011
    Abstract: A method of processing communication signals, is described. The method includes receiving a communication signal in a time domain, converting the communication signal to a frequency domain, providing resource blocks, the resource blocks including a first resource block and a second resource block, the first having a first boundary and a second boundary, the first boundary being adjacent to the second resource block, the second boundary being non-adjacent to other resource blocks, the first resource block including pilot signals, generating a third resource block based on the one or more pilot signals, providing a first waveform based on the resource blocks and the third resource block, applying a smoothing filter against the first waveform to generate a second waveform, generating a third waveform using at least the first and third set of phase and amplitude differences, and converting the third waveform from the frequency domain to the time domain.
    Type: Application
    Filed: April 28, 2013
    Publication date: November 5, 2015
    Inventors: Xuqiang SHEN, Qiang CAO, Xiaojian DONG
  • Publication number: 20150189625
    Abstract: A method and device for detecting DCI are provided. The method includes: obtaining intermediate data in DCI blind detection, the intermediate data including descrambled data, decoded data and detected RNTI values; determining data to be processed from the decoded data based on a matching result of the detected RNTI values and configured RNTI values; performing encoding, rate matching and modulation on the data to be processed to obtain modulated data; calculating confidence levels of the configured RNTI values based on the modulated data and the descrambled data; and when a maximum confidence level of the configured RNTI value is greater than a predetermined threshold of confidence level, determining that the data to be processed contains detected DCI. The probability of DCI misdetection may be reduced, and further the accuracy of uplink and downlink data on a mobile terminal and system stability may be ensured.
    Type: Application
    Filed: July 23, 2014
    Publication date: July 2, 2015
    Inventors: Xuqiang SHEN, Xiaojian DONG
  • Patent number: 9071475
    Abstract: Methods and communication terminals for estimating noise in a multicarrier communication system, where multicarrier symbols are received that include pilot signals, channel properties are estimated based on the received multicarrier symbols, wherein the channel properties include channel properties of a subcarrier carrying one of the pilot signals, and the channel properties of the subcarrier carrying one of the pilot signals are mixed with the corresponding pilot signal to calculate a noise power for the corresponding subcarrier.
    Type: Grant
    Filed: December 19, 2012
    Date of Patent: June 30, 2015
    Assignee: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Xiaojian Dong
  • Publication number: 20150126182
    Abstract: A mobile communication method based on a mobile communication terminal is provided, wherein a communication unit of the mobile communication terminal is adapted to working in at least two communication modes, and an antenna assembly of the mobile communication terminal is adapted to selectively working in different communication modes or in a combination of different communication modes. The method includes: selecting, based on a communication mode and a service type of the mobile communication terminal, a coupling relationship between the antenna assembly and the communication unit, so that the mobile communication terminal can work in various working modes; and if the communication mode and/or the service type of the mobile communication terminal changes, adjusting the coupling relationship between the antenna assembly and the communication unit based on the change. The mobile communication terminal using the method has characteristics of small size, low cost and less difficulty to design.
    Type: Application
    Filed: August 6, 2014
    Publication date: May 7, 2015
    Inventors: Xiaojian DONG, Qiang CAO, Dian XU, Baikui XU, Yu DONG, Xuqiang SHEN
  • Publication number: 20150036650
    Abstract: A method of processing signals. The method includes receiving a communication signal in a time domain, converting the communication signal to a frequency domain, providing resource blocks based on the communication signal in the frequency domain, the resource blocks including a first resource block and a second resource block, selecting pilot signals from the first resource block and pilot signals from the second resource block, determining a first set of phase and amplitude differences among the pilot signals, determining a second set of phase and amplitude differences among the pilot signals, determining a third set of phase and amplitude differences between the pilot signals and the pilot signals, generating a first waveform using at least the first and third set of phase and amplitude differences, applying a smoothing filter against the first waveform to generate a second waveform, and converting the third waveform from the frequency domain to the time domain.
    Type: Application
    Filed: April 7, 2013
    Publication date: February 5, 2015
    Inventors: Xuqiang Shen, Qiang Cao, Xiaojian Dong
  • Publication number: 20140307641
    Abstract: Methods and communication terminals for estimating noise in a multicarrier communication system, where multicarrier symbols are received that include pilot signals, channel properties are estimated based on the received multicarrier symbols, wherein the channel properties include channel properties of a subcarrier carrying one of the pilot signals, and the channel properties of the subcarrier carrying one of the pilot signals are mixed with the corresponding pilot signal to calculate a noise power for the corresponding subcarrier.
    Type: Application
    Filed: December 19, 2012
    Publication date: October 16, 2014
    Applicant: Spreadtrum Communications (Shanghai) Co., Ltd.
    Inventors: Xuqiang Shen, Xiaojian Dong
  • Publication number: 20140307824
    Abstract: Methods and communication terminals for determining rank indication in a multicarrier communication system, wherein communication in the multicarrier communication system is carried out over a plurality of subcarriers, wherein the communication terminal communicates with an interface station within a cell in a multiple-input-multiple-output (MIMO) configuration. In particular, multicarrier symbols are received including pilot signals from the interface station, wherein the pilot signals contain pilot data, and channel properties are estimated based on the received multicarrier symbols, wherein the channel properties include channel properties of at least one subcarrier carrying one of the pilot signals. The pilot data are equalized based on the channel properties for determination of at least one pilot power and at least one interference power based on the equalized pilot data, and a rank indication is determined based on the at least one pilot power and the at least one interference power.
    Type: Application
    Filed: December 19, 2012
    Publication date: October 16, 2014
    Applicant: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang Shen, Xiaojian Dong
  • Publication number: 20140233628
    Abstract: The present invention relates to the field of MIMO wireless communication. Disclosed are a method for combining signals from multiple channels in a multi-antenna receiver and its apparatus. In the present invention, weight values corresponding to each antenna are calculated based on noise estimates or SNRs obtained from channel estimation, and a weighted combination is performed on each signal after channel equalization, which can effectively reduce impact of noises on signals and improve performances of receivers. Weight values are calculated for each subcarrier of each antenna based on noise estimates or SNRs, and a weighted combination is performed in subsequent step, which can further improve performances of OFDM receivers for a OFDM system.
    Type: Application
    Filed: February 17, 2014
    Publication date: August 21, 2014
    Applicant: SPREADTRUM COMMUNICATIONS (SHANGHAI) CO., LTD.
    Inventors: Xuqiang SHEN, Qiang CAO, Xiaojian DONG