Patents Represented by Attorney Kenneth Vu
  • Patent number: 8014271
    Abstract: A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: September 6, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sathyadev Venkata Uppala
  • Patent number: 7990844
    Abstract: A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: August 2, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sathyadev Venkata Uppala
  • Patent number: 7990843
    Abstract: A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: August 2, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sathyadev Venkata Uppala
  • Patent number: 7924781
    Abstract: In a communication system, a method and an apparatus provide for efficient communications of data rate control information. A mobile station communicates a request on a data channel for reception of a data file on a traffic channel. In response to the request, a transmitter in mobile station starts communication of data rate control information on a data rate control channel. After concluding the delivery of a requested data file by a receiver in mobile station, transmitter ceases communication of data rate control information on data rate control channel from mobile station.
    Type: Grant
    Filed: August 29, 2006
    Date of Patent: April 12, 2011
    Assignee: QUALCOMM Incorporated
    Inventor: Yu-Cheun Jou
  • Patent number: 7924699
    Abstract: A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: April 12, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sathyadev Venkata Uppala
  • Patent number: 7916624
    Abstract: A method for reducing the peak-to-average ratio in an OFDM communication signal is provided. The method includes defining a constellation having a plurality of symbols, defining a symbol duration for the OFDM communication signal, and defining a plurality of time instants in the symbol duration. A plurality of tones are allocated to a particular communication device, and a discrete signal is constructed in the time domain by mapping symbols from the constellation to the time instants. A continuous signal is generated by applying an interpolation function to the discrete signal such that the continuous signal only includes sinusoids having frequencies which are equal to the allocated tones.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: March 29, 2011
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sathyadev Venkata Uppala
  • Patent number: 7839308
    Abstract: Systems, methodologies, and devices are described that can facilitate bandwidth efficient non-coherent signaling for uplink control channel transmissions. A communication device (e.g., a mobile device, base station) can be configured to utilize or generate a set of complex orthogonal codewords to facilitate transmission of control channel information using non-coherent signaling in a bandwidth efficient manner. A complex orthogonal codeword set can comprise a first subset of codewords where such codewords have a desirable cross-correlation property and another subset(s) of codewords that can include expurgated codewords, where the expurgated codewords can include discarded codewords and/or codeword pairs that produce a worst-case cross-correlation property. The codeword set and subsets are determined based at least in part on a predefined codeword criterion.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: November 23, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Byoung-Hoon Kim, Dung N. Doan, Durga Prasad Malladi
  • Patent number: 7826489
    Abstract: The present disclosure provides a method and apparatus of channel estimation for a wireless communication system. Dedicated pilot symbols transmitted over at least one time-frequency region for at least one user are received. Channel parameters are estimated for the at least one time-frequency region based on the received dedicated pilot symbols.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: November 2, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Petru Cristian Buidanu, Alexei Gorokhov, Dhananjay A. Gore
  • Patent number: 7801556
    Abstract: A tunable dual-antenna system for multiple frequency band operation is disclosed, which allows a device to switch between multiple frequencies and/or multiple modes, such as CDMA and GSM. The system may comprise a tunable transmit antenna and a tunable receive antenna. One configuration may comprise multiple transmit antennas and multiple receive antennas.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: September 21, 2010
    Assignee: QUALCOMM Incorporated
    Inventor: Allen Minh-Triet Tran
  • Patent number: 7801248
    Abstract: A receiver suppresses co-channel interference (CCI) from other transmitters and intersymbol interference (ISI) due to channel distortion using “virtual” antennas. The virtual antennas may be formed by (1) oversampling a received signal for each actual antenna at the receiver and/or (1) decomposing a sequence of complex-valued samples into a sequence of inphase samples and a sequence of quadrature samples. In one design, the receiver includes a pre-processor, an interference suppressor, and an equalizer. The pre-processor processes received samples for at least one actual antenna and generates at least two sequences of input samples for each actual antenna. The interference suppressor suppresses co-channel interference in the input sample sequences and provides at least one sequence of CCI-suppressed samples. The equalizer performs detection on the CCI-suppressed sample sequence(s) and provides detected bits. The interference suppressor and equalizer may be operated for one or multiple iterations.
    Type: Grant
    Filed: May 4, 2005
    Date of Patent: September 21, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Raghu Challa, Roland Reinhard Rick
  • Patent number: 7764594
    Abstract: In one aspect of a multiple-access OFDM-CDMA system, the data spreading is performed in the frequency domain by spreading each data stream with a respective spreading code selected from a set of available spreading codes. To support multiple access, system resources may be allocated and de-allocated to users (e.g., spreading codes may be assigned to users as needed, and transmit power may be allocated to users). Variable rate data for each user may be supported via a combination of spreading adjustment and transmit power scaling. Interference control techniques are also provided to improve system performance via power control of the downlink and/or uplink transmissions to achieve the desired level of performance while minimizing interference. A pilot may be transmitted by each transmitter unit to assist the receiver units perform acquisition, timing synchronization, carrier recovery, handoff, channel estimation, coherent data demodulation, and so on.
    Type: Grant
    Filed: July 26, 2006
    Date of Patent: July 27, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Jay R. Walton, John W. Ketchum, Steven J. Howard, Mark Wallace
  • Patent number: 7729714
    Abstract: A method and system for reverse link transmit beam-forming. One method comprises using a plurality of antennas at an access terminal to wirelessly transmit signals to one or more base stations; receiving an input indicating a reverse link signal quality at the one or more base stations; and adjusting at least one of a gain and a phase of a signal to be transmitted on one or more antennas. The input may be a reverse power control (RPC) value sent from one or more base stations or a measurement of the closed-loop pilot transmit power.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: June 1, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Peter John Black, Mingxi Fan, Yeliz Tokgoz
  • Patent number: 7693037
    Abstract: A method and system for adapting an effective spreading sequence in a wire-line or a wireless communication system using direct sequence spreading system is described. A station of the communication system determines a state of a communication channel, represented by, e.g., an impulse response, a step response, or any other characteristic known to one skilled in the art. The station determines the channel state by measurements of a received signal or by receiving a feedback signal comprising an information enabling the station to determine the plurality of linearly related phases The station then determines a plurality of linearly related phases in accordance with the state of the communication channel, and then applies at least one of the plurality of linearly related phases to at least one sample of the effective spreading sequence.
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: April 6, 2010
    Assignee: QUALCOMM Incorporated
    Inventor: Hans Dieter Schotten
  • Patent number: 7693241
    Abstract: A rake receiver finger assignor is configured to assign a rake receiver finger to a time offset between identified signal path time offsets in accordance with a concentration of identified signal paths from a transmitter to a rake receiver. In accordance with the exemplary embodiment, a number of identified signal paths having time offsets within a time window are observed to determine the concentration of signal paths identified by a path searcher. If the number of identified signal paths indicates a concentrated distribution of signal paths such as during a fat path condition, at least one rake finger is assigned between at a time offset between two identified signal paths.
    Type: Grant
    Filed: March 28, 2006
    Date of Patent: April 6, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Thejaswi Bharadwaj Madapushi Sheshadri, Brian Dong, Messay Amerga, Chih-Ping Hsu, Parvathanathan Subrahmanya, Xiaoming Zhu
  • Patent number: 7685495
    Abstract: An apparatus and method for interleaving systematic bits and parity bits to generate an output sequence that can be transmitted in multi-slot packets from a base station to a remote station in a wireless communication system. The apparatus comprises a memory element and a control element coupled to the memory element, wherein the control element is configured to demultiplex the systematic bits and parity bits into sequences, wherein the systematic bits and parity bits are sequentially distributed among the sequences. The control element is further configured to reorder the sequences based on an index set, to group the sequences into segments and to interleave each of the segments forming matrices having elements. The control element is also configured to modulate the elements of the matrices, and to truncate the modulated elements of each matrix, so as to produce the output sequence which comprises truncated modulating elements from each matrix of the matrices.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: March 23, 2010
    Assignee: QUALCOMM Incorporated
    Inventor: Naga Bhushan
  • Patent number: 7656843
    Abstract: Methods and apparatus are presented for improving the feedback of channel information to a serving base station, which allows a reduction in the reverse link load while allowing the base station to improve the forward link data throughput. Over a channel quality indicator channel, a carrier-to-interference (C/I) symbol is transmitted over multiple slots at a reduced rate, which increases the likelihood that the base station can decode said symbol. The reduced rate mode can be selectively triggered by a high velocity condition or other unfavorable channel condition. The C/I symbol is used to determine transmission formats, power levels, and data rates of forward link transmissions.
    Type: Grant
    Filed: June 12, 2007
    Date of Patent: February 2, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: David Puig-Oses, Yongbin Wei, Stein A. Lundby
  • Patent number: 7639999
    Abstract: System for diverse path antenna selection. A method is provided for receiving a signal in a communication device having first and second antennas. The method includes receiving a first version of the signal using the first antenna, and receiving a second version of the signal using the second antenna. The method also includes determining a first quality indicator and a second quality indicator associated with the first and second versions of the signal, respectively, and selecting one of the first and second versions of the signal to process based on the first and second quality indicators.
    Type: Grant
    Filed: April 8, 2005
    Date of Patent: December 29, 2009
    Assignee: QUALCOMM Incorporated
    Inventor: Raymond C. Wallace
  • Patent number: 7623861
    Abstract: A wireless mobile telephone (400) is operated so as manage the performance of “off-frequency searches,” that is, searches for base station pilot signals that differ in frequency from the pilot signals in the mobile station's active set. Whenever frequency searching is performed (such as responsive to emerging from a reduced-power sleep mode), the mobile station performs on-frequency pilot signal searching (902) upon a prescribed active set frequency. Only if a prescribed off-frequency searching condition (903-908) is satisfied, the mobile station additionally performs off-frequency pilot signal searching (912) upon one or more neighboring base stations' frequencies.
    Type: Grant
    Filed: December 5, 2002
    Date of Patent: November 24, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Abhay Arvind Joshi, Arthur James Neufeld, Steven Yoon, Thunyachate Ekvetchavit
  • Patent number: 7623553
    Abstract: According to one aspect of the present invention, a method is provided in which indications of signal quality associated with each of the plurality of user stations are received. Multiple user stations (e.g., a first user station and a second user station) are selected to receive data from a base station based on the indications of signal quality associated with the plurality of the user stations. A first packet is constructed which contains signaling data for the first user station and application data for the second user station. A second packet which contains application data for the first user station is super-imposed upon the first packet. The first and second packets are transmitted simultaneously from the base station to the first and second user stations.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: November 24, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Naga Bhushan, Raul Hernan Etkin
  • Patent number: 7620029
    Abstract: This disclosure is directed to cell acquisition techniques for telecommunication systems that implement FDMA and TDMA techniques, such as GSM systems. The techniques make efficient use of processing time in order to accelerate the cell acquisition process. Upon acquiring synchronization information of a first cell of an FDMA system, the timing for the acquisition of cell identification (ID) information associated with the first cell can be scheduled based on the synchronization information of the first cell. Synchronization information of a second cell of the FDMA system can then be acquired prior to acquiring the cell ID information associated with the first cell. Moreover, synchronization information of a additional cells may similarly be acquired prior to acquiring the cell ID information associated with the first cell. In this manner, efficient use of processing time can be achieved between the acquisition of synchronization information and the acquisition of cell ID information.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: November 17, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Roland Rick, David Pandian