Patents by Inventor Shouxing Qu

Shouxing Qu 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: 20090129312
    Abstract: The present disclosure relates generally to systems and methods for timing synchronization. Uplink synchronization is a necessary component of a UE operating in a mobile, wireless network. Reliable uplink synchronization generally requires regular uplink transmission containing reference signals. A method is provided that defines a burst period for sending the reference signals, determines an interval between the reference signals, and sends a timing instruction message that includes the burst period and the determined interval. A second method is provided that receives the timing instruction message and sends the reference signals in accordance with the timing instruction.
    Type: Application
    Filed: November 20, 2007
    Publication date: May 21, 2009
    Applicant: RESEARCH IN MOTION LIMITED
    Inventors: Yongkang Jia, James Earl Womack, Zhijun Cai, Shouxing Qu
  • Publication number: 20080285687
    Abstract: A selective decision-feedback detector for the space-time block code which provides both diversity and spatial multiplexing. To detect a received code block of transmitted symbols, the channel matrix is properly preprocessed with the real and imaginary parts decoupled, and the selective decision-feedback detector makes multiple decisions on the same block upon differently permuted channel matrix and generates multiple candidates for the results. The indicators of the decision errors associated with the candidates are compared, and one of the candidates with the minimum error is selected by a selector as the decided symbols to be used for further processing at a receiving station.
    Type: Application
    Filed: May 17, 2007
    Publication date: November 20, 2008
    Applicant: RESEARCH IN MOTION LIMITED
    Inventor: SHOUXING QU
  • Publication number: 20080187069
    Abstract: Apparatus, and an associated method, for sending a data block in an OFDM, or other MCM, communication system with reduced PAPR is provided. The data block is combined with a random scrambling sequence. An IDFT operation is performed upon the combined sequence, and its PAPR, peak-to-average power ratio, is calculated. The PAPR is compared against a threshold. If the PAPR is smaller than a threshold, the transformed, combination sequence is transmitted. Otherwise, a different scrambling sequence, if available, is used to form a new combination sequence, and the process iterates until either a PAPR smaller than the threshold is obtained, or a pre-defined maximum number of iterations is reached. If the maximum number of iterations is reached and no combination sequence is created that leads to an acceptable PAPR, then the transformed, combination sequence that exhibits the smallest PAPR level is selected for transmission.
    Type: Application
    Filed: February 2, 2007
    Publication date: August 7, 2008
    Applicant: RESEARCH IN MOTION LIMITED
    Inventors: SHOUXING QU, FARZANEH KOHANDANI
  • Publication number: 20080187057
    Abstract: Apparatus, and an associated method, for facilitating communication of a data block communicated in an OFDM-based, communication system. Side-information required to be transmitted by many PAPR reduction schemes in OFDM is carried and transmitted by sending orthogonal binary sequences superimposed on the OFDM data sequence carrying the information to be transmitted. In one embodiment, a selected scrambling sequence is multiplied with an input data block to yield a desired Peak-To-Average Power Ratio. An identification sequence one-to-one corresponding to the scrambling sequence is superimposed on the resultant sequence and transmitted together. In the receiving station, the identification sequence is determined through correlation operations. This also determines the scrambling sequence. The effects of both sequences are finally removed from the information-carrying data sequence.
    Type: Application
    Filed: February 2, 2007
    Publication date: August 7, 2008
    Applicant: RESEARCH IN MOTION LIMITED
    Inventor: SHOUXING QU
  • Publication number: 20070189405
    Abstract: An OFDM system and method using amplitude shift keying (ASK) for subcarrier modulation is provided. Because ASK is used, the signal of each symbol in time domain is conjugate-symmetric. In addition, among the discrete numbers of each symbol, two of them are always real. These properties are utilized such that only half of the numbers of each symbol sequence are transmitted. The generated baseband signal can be a complex or a real signal. As a result, the bandwidth efficiency of the derived ASK-OFDM is the same as that of QAM-OFDM.
    Type: Application
    Filed: February 13, 2007
    Publication date: August 16, 2007
    Inventor: Shouxing Qu