Patents by Inventor Xiaoming She

Xiaoming She 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: 8462877
    Abstract: The present invention relates to a method and apparatus for transmitting/receiving multimedia broadcast/multicast data. The method includes the steps of: receiving a check report returned from a receiver, determining whether the check report indicates there are both basic layer and enhanced layer data errors and if yes, exchanging the last two bits of the enhanced layer and the first two bits of the basic layer and modulating the data with a second constellation map and then transmitting the data; otherwise determining whether the check report indicates there is only the basic layer error, and modulating and transmitting the data according to the result of determination. The beneficial effects of the present invention are that the retransmission efficiency can be improved and the ratio of receiving the data correctly by the users at the cell center and at the cell border during the first retransmission is improved.
    Type: Grant
    Filed: September 10, 2009
    Date of Patent: June 11, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Minghai Feng, Xiaoming She, Lan Chen
  • Publication number: 20130114513
    Abstract: In order to reduce the amount of feedback information for specifying a precoding weight, the mobile station apparatus generates a control signal for specifying the precoding weight using bits representing a rank indicator (RI) and bits representing a precoding matrix indicator (PMI) from a bit space, including a plurality of bits representing the RI and a plurality of bits representing the PMI, in which the same bits representing the RI are allocated to a plurality of ranks equal to or higher than a predetermined rank. The control signal is transmitted in uplink using the antennas.
    Type: Application
    Filed: April 5, 2011
    Publication date: May 9, 2013
    Applicant: NTT DOCOMO, INC.
    Inventors: Hidekazu Taoka, Bijun Zhang, Xiaoming She
  • Publication number: 20130114751
    Abstract: The present invention provides a user equipment and channel state information feedback method. The channel state information feedback method used in a coordinated multi-point system includes acquiring small-scale channel state information H?=[H?1, H?2, . . . , H?K] between a user equipment and all base stations joining coordination, acquiring large-scale channel state information li(i=1, . . . , K) between the user equipment and each of the base stations joining coordination, acquiring a CQI (CQIi=li?|H?|, i=1, . . .
    Type: Application
    Filed: June 17, 2011
    Publication date: May 9, 2013
    Applicant: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Yoshihisa Kishiyama, Xiang Yun, Jianchi Zhu, Xiaoming She, Lan Chen
  • Patent number: 8355340
    Abstract: Embodiments of the present invention include a method and base station for obtaining Channel Quality Indicator (CQI) information. One embodiment of the method includes: receiving, by a base station, quantized channel information, quantization error, Inter-Cell Interference (ICI) power and noise power fed back by each User Equipment (UE) after channel estimation; and estimating, by the base station, a CQI corresponding to each UE to obtain an estimated CQI value corresponding to each UE according to the quantized channel information, the quantization error, the ICI power and the noise power which are fed back by the UE as well as an instantaneous precoding vector or matrix of each UE. Through the embodiments, the base station can obtain more precise CQI information of each UE so as to select a precise modulation and coding scheme and to increase system throughput.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: January 15, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Jianchi Zhu, Xiaoming She, Xiang Yun, Lan Chen
  • Patent number: 8351386
    Abstract: A base station apparatus includes a correction unit for correcting a CQI reported from a user apparatus and a scheduler for scheduling based on the corrected CQI. The correction unit uses a correction table to correct the CQI such that if the reported CQI is poor, the CQI is slightly reduced, and otherwise, the CQI is significantly reduced. One method of generating the correction table includes deriving a first SINR in consideration of the number of interference users less than (n?1) and a second SINR in consideration of the number of interference users equal to (n?1) to explore a distribution of the second SINR to the first SINR. In this method, correspondence between the first SINR and the second SINR is determined based on the distribution to generate the correction table.
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: January 8, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hidekazu Taoka, Jianchi Zhu, Xiaoming She, Lan Chen
  • Patent number: 8340705
    Abstract: Methods of camping on a hybrid cell and checking access priority and devices therefor are provided. The service of a CSG user is preferably guaranteed by adjusting a UE's camping right and a passing probability of an access priority checking according to the user's contracted characteristic and limit access information of a hybrid cell Node B. At the same time, the initial access delay of a non-CSG user is reduced, the initial access efficiency of the non-CSG user is improved, and the network resource and the UE's power are saved.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: December 25, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Liu Liu, Xiaoming She, Lan Chen, Yixue Lei, Mikio Iwamura
  • Patent number: 8254938
    Abstract: Embodiments of the present invention disclose a method for coordinated multi-cell transmission, a central controller and a User Equipment (UE). In one embodiment, the method includes: determining, by a central controller, at least one candidate cooperating set in a super-cell, wherein each cell in the super-cell belongs to at least one candidate cooperating set, and broadcasting information of the at least one candidate cooperating set determined to all UEs in the super-cell; selecting, by each UE, a candidate cooperating set from the at least one candidate cooperating set as a cooperating set of the UE, and feeding back information of the cooperating set selected to the central controller; and determining, by the central controller, all cooperating sets in the super-cell and UEs participating in cooperation in each cooperating set according to the information of the selected cooperating set fed back by each UE.
    Type: Grant
    Filed: July 20, 2010
    Date of Patent: August 28, 2012
    Assignee: NTT DOCOMO, Inc.
    Inventors: Jianchi Zhu, Xiaoming She, Xiang Yun, Lan Chen
  • Patent number: 8249613
    Abstract: A method of data processing includes the steps of: dividing user terminals into groups based on channel attributes and service requirements of the user terminals and setting a precoding code word and a cyclic delay for each of the groups; and determining which group a user terminal corresponding to the data to be processed belongs to and processing the data to be processed by the Cyclic Delay Diversity (CDD) precoding based on the precoding code word and the cyclic delay of the group. A data processing apparatus includes a grouping module and a CDD preceding module. By the method and apparatus above, the signal quality in the MIMO system can be improved.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: August 21, 2012
    Assignee: NTT DoCoMo Inc.
    Inventors: Jingxiu Liu, Xiaoming She, Lan Chen, Hidekazu Taoka
  • Patent number: 8224252
    Abstract: An inter-cell interference coordination method comprises: measuring an interference over thermal noise of a first subcarrier resource block in an uplink direction and obtaining an interference over thermal noise measurement value by a first base station; judging whether a first high interference indicating message is received from a second base station when the interference over thermal noise measurement value is larger than a first preset threshold value by the first base station; sending an overload indicator message to the second base station which has sent the high interference indicating message or shielding the first subcarrier resource block by the first base station when the first high interference indicating message is received; and sending the overload indicator message to base stations to which all the neighboring cells belong by the first base station when the first high interference indicating message is not received. The overhead at X2 interface is reduced according to the present invention.
    Type: Grant
    Filed: June 8, 2010
    Date of Patent: July 17, 2012
    Assignee: NTT Docomo, Inc.
    Inventors: Minghai Feng, Xiaoming She, Lan Chen, Wenbo Wang, Mugen Peng, Dong Liang, Song Zhu
  • Publication number: 20110274197
    Abstract: The present invention provides a method for transmitting MIMO related information. The method includes: encoding MIMO related information of a user equipment (UE) by a base station, and transmitting downlink control signaling including a result of the encoding; receiving by the UE the downlink control signaling transmitted by the base station, obtaining the result of the encoding, and obtaining the MIMO related information of the UE by decoding the result of the encoding. By adopting the method, the base station is enabled to transmit MIMO related information required by the UE to the UE with small signaling overhead.
    Type: Application
    Filed: May 3, 2011
    Publication date: November 10, 2011
    Applicant: NTT DoCoMo, Inc.
    Inventors: Jianchi Zhu, Xiaoming She, Lan Chen, Hidekazu Taoka, Hirohito Suda
  • Patent number: 8009754
    Abstract: A wireless communication system capable of achieving adaptive STTD (Space-time Transmit Diversity). In this system, a receiving apparatus uses a channel estimation to calculate SINR (Signal to Interference and Noise Ratio) of each of substreams in all the combinations of transmission antennas and also calculate the performance of the whole system in all the combinations of transmission antennas, thereby deciding a particular combination, which provides the best performance of the whole system, and obtaining a parameter for antenna selection. The SINR of each substream in the decided particular combination is used to decide an AMC parameter. A transmitting apparatus performs STTD and AMC based on the AMC parameter fed back from the receiving apparatus, and further selects, based on the antenna selection parameter fed back from the receiving apparatus, a particular combination of transmission antennas for performing a transmission.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: August 30, 2011
    Assignee: Panasonic Corporation
    Inventors: Xiaoming She, Jifeng Li
  • Patent number: 7920640
    Abstract: A transmission bit and transmission power distributing method that can reduce the arithmetic amount in a multiantenna-input/multiantenna-output (MIMO) wireless communication system. This method comprises steps of calculating a signal-to-interference-noise ratio (SINR) gain after MIMO detection of each of transport substreams (S601, S602); optimizing, based on the acquired SINR gain, a transmission bit and transmission power distribution in the space domain for all transport substreams on a particular subcarrier in the frequency domain, thereby deciding a transmission bit and transmission power distribution parameters (S603, S604); and optimizing a transmission bit and transmission power distribution for adjacent subcarriers, by sequentially using the transmission bit and transmission power distribution parameters distributed on the subcarrier for which the transmission bit and transmission power distribution parameters have been decided (S605 to S610).
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: April 5, 2011
    Assignee: Panasonic Corporation
    Inventors: Xiaoming She, Jifeng Li
  • Patent number: 7912141
    Abstract: A pre-coding method for a MIMO system and an apparatus using the same are described. In the method, a receiver determines a corresponding codebook from a multi-codebook including multiple codebooks according to a location of a resource block, selects a corresponding codeword index from the determined codebook and transmits the index to a transmitter; the transmitter determines the corresponding codebook from the multi-codebook including multiple codebooks according to the location of the resource block where transmission data is to be transmitted, selects a corresponding codeword from the determined codebook according to the codeword index and performs pre-coding for the transmission data with the selected codeword. The pre-coding is performed with the multi-codebook in the present invention, which increases a diversity of pre-coding matrixes, so dynamic fluctuation range of a equivalent channel is improved and thus the performance of multi-user scheduling is enhanced effectively.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: March 22, 2011
    Assignee: NTT Docomo, Inc.
    Inventors: Xiaoming She, Jingxiu Liu, Lan Chen, Kenichi Higuchi
  • Publication number: 20110045856
    Abstract: An inter-cell interference coordination method comprises: measuring an interference over thermal noise of a first subcarrier resource block in an uplink direction and obtaining an interference over thermal noise measurement value by a first base station; judging whether a first high interference indicating message is received from a second base station when the interference over thermal noise measurement value is larger than a first preset threshold value by the first base station; sending an overload indicator message to the second base station which has sent the high interference indicating message or shielding the first subcarrier resource block by the first base station when the first high interference indicating message is received; and sending the overload indicator message to base stations to which all the neighboring cells belong by the first base station when the first high interference indicating message is not received. The overhead at X2 interface is reduced according to the present invention.
    Type: Application
    Filed: June 8, 2010
    Publication date: February 24, 2011
    Inventors: Minghai Feng, Xiaoming She, Lan Chen, Wenbo Wang, Mugen Peng, Dong Liang, Song Zhu
  • Publication number: 20110039594
    Abstract: Methods of camping on a hybrid cell and checking access priority and devices therefor are provided. The service of a CSG user is preferably guaranteed by adjusting a UE's camping right and a passing probability of an access priority checking according to the user's contracted characteristic and limit access information of a hybrid cell Node B. At the same time, the initial access delay of a non-CSG user is reduced, the initial access efficiency of the non-CSG user is improved, and the network resource and the UE's power are saved.
    Type: Application
    Filed: August 13, 2010
    Publication date: February 17, 2011
    Inventors: Liu LIU, Xiaoming She, Lan Chen, Yixue Lei, Mikio Iwamura
  • Patent number: 7890115
    Abstract: A method of scheduling resources in an uplink of a wireless cellular communication system, comprising the steps of measuring, by each user equipment in a present cell, pilot strengths of adjacent cells to find base stations within adjacent cells on which the user equipment has the strongest inter-cell interferences and to calculate values of the inter-cell interferences in an uplink direction which is caused by the user equipment on said base stations within said adjacent cells; grouping all user equipments within the present cell based on the calculated values of the inter-cell interferences; grouping used sub-carriers based on the groups of the user equipments so that each group of user equipments corresponds to one group of sub-carriers; allocating each group of sub-carriers to the user equipments included in the group of user equipments selected corresponding to the group of sub-carriers; and based on the allocation of the group of the sub-carriers, calculating a modified signal noise interference power r
    Type: Grant
    Filed: November 1, 2007
    Date of Patent: February 15, 2011
    Assignee: NTT DoCoMo, Inc.
    Inventors: Minghai Feng, Xiaoming She, Lan Chen
  • Publication number: 20110034163
    Abstract: Embodiments of the present invention disclose a method for coordinated multi-cell transmission, a central controller and a User Equipment (UE). In one embodiment, the method includes: determining, by a central controller, at least one candidate cooperating set in a super-cell, wherein each cell in the super-cell belongs to at least one candidate cooperating set, and broadcasting information of the at least one candidate cooperating set determined to all UEs in the super-cell; selecting, by each UE, a candidate cooperating set from the at least one candidate cooperating set as a cooperating set of the UE, and feeding back information of the cooperating set selected to the central controller; and determining, by the central controller, all cooperating sets in the super-cell and UEs participating in cooperation in each cooperating set according to the information of the selected cooperating set fed back by each UE.
    Type: Application
    Filed: July 20, 2010
    Publication date: February 10, 2011
    Inventors: Jianchi Zhu, Xiaoming She, Xiang Yun, Lan Chen
  • Publication number: 20110032835
    Abstract: Embodiments of the present invention include a method and base station for obtaining Channel Quality Indicator (CQI) information. One embodiment of the method includes: receiving, by a base station, quantized channel information, quantization error, Inter-Cell Interference (ICI) power and noise power fed back by each User Equipment (UE) after channel estimation; and estimating, by the base station, a CQI corresponding to each UE to obtain an estimated CQI value corresponding to each UE according to the quantized channel information, the quantization error, the ICI power and the noise power which are fed back by the UE as well as an instantaneous precoding vector or matrix of each UE. Through the embodiments, the base station can obtain more precise CQI information of each UE so as to select a precise modulation and coding scheme and to increase system throughput.
    Type: Application
    Filed: June 22, 2010
    Publication date: February 10, 2011
    Inventors: Jianchi Zhu, Xiaoming She, Xiang Yun, Lan Chen
  • Patent number: 7860184
    Abstract: A multi-antenna communication method capable of improving the retransmission performance in a multi-antenna transmission. In this method, firstly, the reception quality of a substream to be retransmitted is acquired (Step 401). Then, it is determined for the substream whether any transmission antennas, which satisfy a target value related to the foregoing reception quality when they are used for the retransmission, are existent among the transmission antennas that are candidate antennas to be used for there transmission (Step 405). Then, if there exist any transmission antennas satisfying the target value, a transmission antenna to which the poorest channel characteristic corresponds is selected from among those transmission antennas satisfying the target value, and the selected transmission antenna is designated as an antenna to be used for retransmitting the foregoing substream (Step 406).
    Type: Grant
    Filed: January 10, 2006
    Date of Patent: December 28, 2010
    Assignee: Panasonic Corporation
    Inventors: Xiaoming She, Jifeng Li
  • Patent number: 7848439
    Abstract: A communication apparatus capable of improving the spectrum usage rate of a system, especially, the spectrum usage rate in connection with both a fast fading and a channel estimation error as compared with the conventional sub-band adaptive method, while reducing the degree of the difficulty in achieving the adaptation, and further reducing the feedback overhead. In this apparatus, a sub-band group AMC parameter selecting part (318) selects an AMC parameter of each sub-band. An adaptive reception control part (503) must control an adaptive demodulating/decoding part (311), while controlling a parallel/serial converter (312) in a stage preceding the adaptive demodulation and decoding processes, and combining received symbols in the same sub-band group for demodulation and decoding.
    Type: Grant
    Filed: November 18, 2005
    Date of Patent: December 7, 2010
    Assignee: Panasonic Corporation
    Inventors: Xiaoming She, Jifeng Li