Patents by Inventor Xiliang Luo

Xiliang Luo 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: 8768359
    Abstract: Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: July 1, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Tao Luo, Kapil Bhattad, Xiaoxia Zhang, Taesang Yoo, Xiliang Luo, Ke Liu
  • Publication number: 20140161043
    Abstract: Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell.
    Type: Application
    Filed: February 17, 2014
    Publication date: June 12, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Tao Luo, Kapil Bhattad, Xiaoxia Zhang, Taesang Yoo, Xiliang Luo, Ke Liu
  • Publication number: 20140161044
    Abstract: Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell.
    Type: Application
    Filed: February 17, 2014
    Publication date: June 12, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Tao Luo, KAPIL BHATTAD, XIAOXIA ZHANG, TAESANG YOO, XILIANG LUO, KE LIU
  • Patent number: 8737502
    Abstract: Techniques for transmitting data from multiple transmit antennas using space orthogonal resource transmit diversity (SORTD) are described. For the SORTD scheme, a different orthogonal resource may be assigned to each transmit antenna. Data may be sent from the multiple transmit antennas using multiple orthogonal resources. In one design, a UE may process at least one information bit (e.g., with joint or independent coding) to obtain first and second sets of at least one modulation symbol. The UE may process the first set of modulation symbol(s) for transmission from the first transmit antenna using a first orthogonal resource. The UE may process the second set of modulation symbol(s) for transmission from the second transmit antenna using a second orthogonal resource. Each orthogonal resource may include a different reference signal sequence or a different set of reference signal sequence and orthogonal sequence.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: May 27, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Peter Gaal, Wanshi Chen, Juan Montojo, Xiaoxia Zhang
  • Patent number: 8730933
    Abstract: Certain aspects of the present disclosure allow reference and data-conveying modulations symbols to be multiplexed in the time domain to form an SC-FDM waveform.
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: May 20, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Juan Montojo, Tao Luo
  • Patent number: 8712401
    Abstract: A method for communicating in an advanced long term evolution (LTE-A) network using common reference signal (CRS) resources associated with different interference levels due to resource partitioning is disclosed. Signals are received from an eNodeB indicating a subset of CRS resources for radio link monitoring (RLM) and/or reference signal received power (RSRP) measuring. The subset of CRS resources includes the CRS resources expected to have lower interference from the interfering eNodeBs. RLM and/or RSRP measurements are performed based on the indicated subset.
    Type: Grant
    Filed: April 12, 2011
    Date of Patent: April 29, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Taesang Yoo, Tao Luo, Xiliang Luo
  • Patent number: 8712424
    Abstract: System(s) and method(s) are provided for inter-cell power control in the presence of fractional frequency reuse in a wireless communication system. Transmission power control of a terminal (210); and ensuing inter-cell interference mitigation, is accomplished by receiving load indicators (23Oi) from non-serving sectors (246i), decoding those load indicators corresponding to the non-serving sectors that operate in the same frequency bands as the terminal, and adjusting the transmission power according to the states of the decoded load indicators in conjunction with the associated non-serving sector forward link signal-to-interference and-noise ratio at the terminal. The states of the load indicators reflect magnitudes of interference metrics with respect to threshold values. Load indicators can also be conveyed by the non-serving sector to a base station (260) serving the terminal through a backhaul (250) communication, and said base station can schedule an adjusted transmission power for the terminal.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: April 29, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Durga Prasad Malladi, Xiaoxia Zhang
  • Patent number: 8688163
    Abstract: Methods and apparatus in a wireless communication system are described for receiving and processing transmit power control commands, where, for example, the response to the transmit power control commands is conditionally decoupled from at least one of a transmit bandwidth parameter, a transport format parameter and a power stepsize limit. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the disclosed subject matter. Therefore, it is to be understood that it should not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: April 1, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Wanshi Chen, Peter Gaal, Juan Montojo, Taesang Yoo, Xiliang Luo, Tao Luo, Yongbin Wei, Naga Bhushan
  • Patent number: 8687731
    Abstract: Systems and methodologies are described that facilitate cycling through precoders for transmitting wireless network communications in a time domain. The precoders can be cycled according to a precoder sequence for each data symbol transmission. When the last precoder is selected the cycle can begin again, a new precoder sequence can be received or defined, and/or the like. A precoder sequence related to a subset of precoders present in a wireless device can be defined sequentially, cyclically shifted according to an identifier or one or more communications parameters, randomly, pseudo-randomly according to an identifier or one or more communications parameters, and/or the like. In addition, the precoder sequence can be utilized to select a precoder for one or more retransmissions. Such cycling of precoders can increase transmit diversity.
    Type: Grant
    Filed: February 1, 2010
    Date of Patent: April 1, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Peter Gaal, Xiliang Luo, Wanshi Chen, Juan Montojo, Xiaoxia Zhang
  • Patent number: 8687728
    Abstract: A method of wireless communication is disclosed which includes acquiring a first set of precoding matrices for a set of frequency bands and generating a second set of precoding matrices for the set of frequency bands based on the first set of precoding matrices. The second set of precoding matrices enables a transmission that satisfies a cubic metric criteria in multiple-in multiple-out communication mode in the uplink. In some designs, generating the second set of precoding matrices can be based on restricting the first set of precoding matrices for a set of frequency bands and transmission rank, rotating the first set of precoding matrices based for a predetermined transmission rank, or a combination thereof.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: April 1, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Peter Gaal, Juan Montojo
  • Patent number: 8670410
    Abstract: In a multi-carrier wireless communication system, component carrier configuration and reconfiguration uses uplink control channel resource mapping with fallback configurations to maintain alignment between a user equipment and a base station during reconfiguration.
    Type: Grant
    Filed: September 14, 2011
    Date of Patent: March 11, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Peter Gaal, Wanshi Chen
  • Patent number: 8670396
    Abstract: Systems and methods for resource allocation for an uplink control channel for a user equipment (UE) using multiple transmit antennas in a wireless communication network are disclosed. A plurality of orthogonal resources for use by the UE on the uplink control channel is selected. Control information is transmitted from the UE on the uplink control channel on the plurality of orthogonal resources with transmit diversity.
    Type: Grant
    Filed: September 24, 2010
    Date of Patent: March 11, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Wanshi Chen, Jelena M. Damnjanovic, Peter Gaal, Juan Montojo
  • Patent number: 8660600
    Abstract: Methods, systems, apparatus and computer program products are provided to facilitate power control in wireless communication systems. A cell that is experiencing excessive interference conditions may generate an over-the-air overload indicator indicative of interference conditions at the cell. The over-the-air overload indicator is received by one or more user equipment in a neighboring cell. In response, the user equipment determines adjustments to its transmit power that reduce and/or eliminate the interference. This determination may be carried out by the user equipment, by the serving base station, or through cooperation between the user equipment and the serving base station. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules that allow a reader to quickly ascertain the disclosed subject matter. Therefore, it is to be understood that it should not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: February 25, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Aamod D. Khandekar, Ravi Palanki, Mohammad J. Borran, Kapil Bhattad, Xiliang Luo
  • Patent number: 8655282
    Abstract: A frontend receiver of a user equipment (UE) is configured with multiple transform operations assigned to separate sets of cells. One set of cells includes the serving cell of the UE and at least one additional cell within a first offset range of the serving cell. Another set or sets of cells include additional interferer cells within another offset range of the serving cell. After tracking the common frequency/timing offsets of each set of cells the assigned transform operation for that set transforms the time domain samples into frequency domain symbols. The individual frequency/timing offsets for each cell within the set are then tracked.
    Type: Grant
    Filed: October 24, 2011
    Date of Patent: February 18, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Taesang Yoo, Tao Luo
  • Patent number: 8644409
    Abstract: Systems and methodologies are described herein that facilitate improved modulation and coding techniques for a multiple-in multiple-out (MIMO) communication system. As described herein, data to be transmitted over a set of physical layers (e.g., corresponding to antennas, beams, etc.) can be processed such that encoding is performed on a per-codeword basis and modulation is performed on a per-layer basis, thereby mitigating performance degradation experienced by traditional systems due to layer imbalance. As further described herein, per-codeword code rate parameters and per-layer modulation parameters can be signaled to a device in various manners, such as through modulation and coding scheme (MCS) signaling, explicit code rate and/or modulation scheme signaling, relative code rate and/or modulation scheme signaling, or the like.
    Type: Grant
    Filed: February 8, 2010
    Date of Patent: February 4, 2014
    Assignee: Qualcomm Incorporated
    Inventors: Alexei Y. Gorokhov, Juan Montojo, Xiaoxia Zhang, Peter Gaal, Xiliang Luo
  • Patent number: 8638684
    Abstract: A method, computer program product, and apparatus are provided in which a request for a channel state information (CSI) report is received on a component carrier of a plurality of component carriers. The request indicates a set of component carriers of the plurality of component carriers for which to provide the CSI report. In addition, a CSI report including feedback for each of the indicated component carriers in the set of component carriers is transmitted. A method, computer program product, and apparatus are provided in which a request for a CSI report on a component carrier of a plurality of component carriers is transmitted. The request indicates a set of component carriers of the plurality of component carriers for which to receive the CSI report. In addition, a CSI report including feedback for each of the indicated component carriers in the set of component carriers is received.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: January 28, 2014
    Assignee: QUALCOMM
    Inventors: Xiliang Luo, Xiaoxia Zhang, Peter Gaal, Hao Xu, Wanshi Chen, Juan Montojo, Tao Luo
  • Patent number: 8619544
    Abstract: A method and apparatus facilitating transmit diversity for control information communications is provided. The method may comprise processing received content, generating control information in response to the processed content, allocating two or more resources associated with two or more transmit antennas for transmitting the control information using a transmit diversity scheme, and determining cyclic shifts by applying a predetermined cyclic shift delta parameter.
    Type: Grant
    Filed: September 22, 2009
    Date of Patent: December 31, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Peter Gaal, Juan Montojo, Xiliang Luo, Xiaoxia Zhang
  • Publication number: 20130343348
    Abstract: Provided is a method for wireless communication which includes transmitting codewords according to an initial transmission rank, receiving downlink transmissions indicating at least one of the codewords to be retransmitted, constructing a demodulation reference signal (DM-RS) to be sent with the at least one codeword to be retransmitted, and retransmitting the at least one codeword with the DM-RS according to a retransmission rank. The downlink transmissions may include one or more physical hybrid automatic retransmission request indicator channels and the DM-RS may be constructed based at least in part on information in the downlink transmissions.
    Type: Application
    Filed: August 26, 2013
    Publication date: December 26, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Xiliang Luo, Peter Gaal, Wanshi Chen, Juan Montojo
  • Publication number: 20130330084
    Abstract: Methods and systems for remotely controlling a device are provided. A first input is received from a user at a portable device. The first input specifies a first time and a first mode associated with the device. At the first time, a first command is remotely sent from the portable device to the device to activate the device in the first mode.
    Type: Application
    Filed: July 30, 2013
    Publication date: December 12, 2013
    Applicant: O2Micro Inc.
    Inventors: Sterling DU, Qiang Guan, Weitai Yang, Xiliang Luo, Shusheng Ma, Yating Li, Yang Wang, Xinsheng Peng, Jing Chen, Ming Li
  • Patent number: 8548383
    Abstract: Systems and methodologies are described that facilitate adjusting power spectrum density (PSD) for wireless devices according to multiple possible step sizes. A step size for an adjustment can be selected based at least in part on a received overload indicator from one or more access points, a PSD required to achieve a target signal-to-interference-and-noise ratio (SINR) for a wireless device, and a PSD previously assigned to the wireless device. Once the step size is selected, it can be applied to the previous PSD to generate a new PSD for the wireless device, and the wireless device can accordingly adjust PSD to mitigate inter-cell interference with the one or more access points.
    Type: Grant
    Filed: August 26, 2009
    Date of Patent: October 1, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xiliang Luo, Rashid Ahmed Akbar Attar, Christopher Gerard Lott