Patents by Inventor Sundeep Rangan

Sundeep Rangan 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: 8571493
    Abstract: Transmit and/or receive diversity is achieved using multiple antennas. In some embodiments, a single transmitter chain within a wireless terminal is coupled over time to a plurality of transmit antennas. At any given time, a controllable switching module couples the single transmitter chain to one the plurality of transmit antennas. Over time, the switching module couples the output signals from the single transmitter chain to different transmit antennas. Switching decisions are based upon predetermined information, dwell information, and/or channel condition feedback information. Switching is performed on some dwell and/or channel estimation boundaries. In some OFDM embodiments, each of multiple transmitter chains is coupled respectively to a different transmit antenna. Information to be transmitted is mapped to a plurality of tones. Different subsets of tones are formed for and transmitted through different transmit chain/antenna sets simultaneously.
    Type: Grant
    Filed: October 26, 2009
    Date of Patent: October 29, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan, Frank A. Lane, Prashanth Hande
  • Patent number: 8548515
    Abstract: Provided is an feedback mechanism to correct power control information in a broadcast signal that is determined to be incorrect by one or more devices that receive and rely on the broadcast information. A device that receives the incorrect broadcast information can determine a correction and to the information and provide a recommendation to tilt source of the broadcast information. The source can selectively determine whether to modify the broadcast information based on the recommendation from one or more devices. If the broadcast information is modified, subsequent devices that receive the broadcast information are provided with the modified information. If further changes are needed, the subsequent devices can provide further recommended changes.
    Type: Grant
    Filed: April 15, 2011
    Date of Patent: October 1, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Samel Celebi, Charles Stanski, Sundeep Rangan
  • Patent number: 8547857
    Abstract: Systems and methodologies are described that facilitate scheduling uplink transmissions. For instance, a time sharing scheme can be utilized such that differing mobile devices can be scheduled to transmit during differing time slots; however, it is also contemplated that a static scheme can be employed. Pursuant to an illustration, an interference budget can be combined with a time varying weighting factor associated with a base station; the weighting factor can be predefined and/or adaptively adjusted (e.g., based upon a load balancing mechanism). Moreover, the weighted interference budget can be leveraged for selecting mobile devices for uplink transmission (e.g., based at least in part upon path loss ratios of the mobile devices). Further, disparate interference budgets can be utilized by differing channels of a sector at a particular time. Also, for example, a base station can assign a loading factor to be utilized by wireless terminal(s) for generating channel quality report(s).
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: October 1, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xinzhou Wu, Sundeep Rangan, Prashanth Hande, Arnab Das, Junyi Li
  • Publication number: 20130230027
    Abstract: A wireless terminal determines the transmission power used for its dedicated control channel at a point in time, and generates a power report indicating a ratio of a maximum wireless terminal transmit power to the transmit power of the dedicated control channel at the point in time. The power report provides a measure of available transmit power for wireless terminal use for other purposes, e.g., uplink traffic channels, after taking into consideration the transmit power used for the dedicated control channel. The point in time has a known time offset from the start of a communications segment in which the power report is transmitted. This allows the base station receiving dedicated control channel uplink signals from the wireless terminal to measure the received signals, receive and process the communicated power report, and correlate information to be used for accurate wireless terminal closed loop power control.
    Type: Application
    Filed: October 17, 2012
    Publication date: September 5, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Arnab Das, Sundeep Rangan
  • Patent number: 8520699
    Abstract: The apparatus and methods described herein are used to provide a communication quality feedback of an end-to-end communication path between an application transmitter and an application receiver. One method includes transmitting data from the application transmitter to the application receiver via the end-to-end communication path, the end-to-end communication path having at least one wireless link with a wireless transmitter and a wireless receiver, generating, at the wireless transmitter, a first communication quality feedback message, and transmitting the first communication quality feedback message from the wireless transmitter to the application transmitter in a standardized format.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: August 27, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Niranjan N. Ratnakar, Prashanth Hande, Sundeep Rangan, Atul Maharshi, Subhadeep P. Roy, Ritesh K. Madan, Ozge Koymen, Siddharth Ray
  • Patent number: 8520723
    Abstract: The apparatus and methods described herein are used to provide data between an application and a modem. One method includes providing data in application data units from the application to the modem, transmitting the data from the modem to a receiver, and reporting by the modem to the application, whether each application data unit has been successfully transmitted from the modem to the receiver.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: August 27, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Sundeep Rangan, Prashanth Hande, Niranjan N. Ratnakar, Ozge Koymen, Ritesh K. Madan, Atul Maharshi, Subhadeep P. Roy, Siddharth Ray
  • Patent number: 8514771
    Abstract: A wireless terminal determines the transmission power used for its dedicated control channel at a point in time, and generates a power report indicating a ratio of a maximum wireless terminal transmit power to the transmit power of the dedicated control channel at the point in time. The power report provides a measure of available transmit power for wireless terminal use for other purposes, e.g., uplink traffic channels, after taking into consideration the transmit power used for the dedicated control channel. The point in time has a known time offset from the start of a communications segment in which the power report is transmitted. This allows the base station receiving dedicated control channel uplink signals from the wireless terminal to measure the received signals, receive and process the communicated power report, and correlate information to be used for accurate wireless terminal closed loop power control.
    Type: Grant
    Filed: January 17, 2006
    Date of Patent: August 20, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Arnab Das, Sundeep Rangan
  • Patent number: 8514692
    Abstract: Methods and apparatus for collecting, measuring, reporting and/or using information which can be used for interference control purposes. Wireless terminals measure signals transmitted from one or more base stations, e.g., base station sector transmitters. The measured signals may be, e.g., beacon signals and/or pilot signals. From the measured signals, the wireless terminal generates one or more gain ratios which provide information about the relative gain of the communications channels from different base station sectors to the wireless terminal. This information represents interference information since it provides information about the signal interference that will be caused by transmissions from other base station sectors relative to transmissions made by the base station sector to which the wireless terminal is attached.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: August 20, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan, Prashanth Hande
  • Patent number: 8503938
    Abstract: A wireless terminal receives and measures broadcast reference signals, e.g., beacon and/or pilot signals, transmitted from a plurality of base station attachment points. The wireless terminal monitors for and attempts to recover broadcast loading factor information corresponding to attachment points. The wireless terminal generates and transmits an interference report to a current attachment point, the report based on the results of a measured received reference signal from the current attachment point, a measured received reference signal from each of one or more different attachment points, and uplink loading factor information. In the absence of a successfully recovered broadcast uplink loading factor corresponding to an attachment point, the wireless terminal uses a default value for that loading factor.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: August 6, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan, Prashanth Hande, Arnab Das
  • Patent number: 8477684
    Abstract: Techniques for sending control messages are described. In an aspect, assignment messages may be acknowledged based on either linked or dedicated acknowledgement (ACK) resources. A terminal may receive an assignment message from a base station, determine whether to acknowledge the assignment message, and determine ACK resources to use to acknowledge the assignment message. The ACK resources may be linked to a control block on which the assignment message was received, linked to resources given by the assignment message, or assigned to the terminal. The terminal may send the acknowledgement on the ACK resources. In another aspect, a control message may be acknowledged based on ACK resources determined based on the control message or the control block. The ACK resources may be linked to resources assigned by the control message or linked to the control message. The terminal may send an acknowledgement for the control message on the ACK resources.
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: July 2, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Aamod Khandekar, Alexei Gorokhov, Avneesh Agrawal, Sundeep Rangan, Arnab Das
  • Patent number: 8451961
    Abstract: Various schemes for reducing effects of interference within communication systems are disclosed. A transmitter transmits a signal in a first time interval and a scrambled version of the signal in a second time interval, which does not overlap with the first time interval. A receiver receives a composite signal including a signal transmitted from the desired transmitter as well as signals from interferers in the first or the second time interval. The receiver determines a dominant interferer and obtains knowledge of signal scrambling done by the interferer as well as the desired transmitter by sensing an identification associated with the interferer or the desired transmitter. This knowledge is employed to determine coefficients for combining the received composite signals received in the first and the second time interval in order to recover the desired signal in a manner that maximizes the SNR associated with the desired signal or completely cancels the dominant interference.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: May 28, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Sundeep Rangan, Junyi Li, Thomas Richardson, Saurabh Tavildar
  • Patent number: 8432852
    Abstract: The claimed subject matter relates to systems and methodologies for synchronizing timing between a base station and a wireless terminal. For example, a set of non-contiguous tones may be assigned to the terminal, and may be equally spaced apart from each other across a spectrum of all available tones. A set of contiguous tones may also be assigned to the terminal, which may transmit a timing control signal during a specified transmit time. A base station may receive the signal, which comprises information related to the non-contiguous and contiguous tone sets, and may determine a distance of the terminal to the base station based on measured and anticipated arrival time of the signal. The base station may transmit a timing correction command signal to the terminal based on such information.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: April 30, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Sundeep Rangan, Junyi Li
  • Patent number: 8411646
    Abstract: Systems and methodologies are described that facilitate scheduling uplink transmissions. For instance, a time sharing scheme can be utilized such that differing mobile devices can be scheduled to transmit during differing time slots; however, it is also contemplated that a static scheme can be employed. Pursuant to an illustration, an interference budget can be combined with a time varying weighting factor associated with a base station; the weighting factor can be predefined and/or adaptively adjusted (e.g., based upon a load balancing mechanism). Moreover, the weighted interference budget can be leveraged for selecting mobile devices for uplink transmission (e.g., based at least in part upon path loss ratios of the mobile devices). Further, disparate interference budgets can be utilized by differing channels of a sector at a particular time. Also, for example, a base station can assign a loading factor to be utilized by wireless terminal(s) for generating channel quality report(s).
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: April 2, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Xinzhou Wu, Sundeep Rangan, Prashanth Hande, Arnab Das, Junyi Li
  • Patent number: 8355455
    Abstract: Channel estimates respectively associated with OFDM pilot symbols are used to estimate additional parameters such as change in channel phase over time, change in channel phase over frequency, and frequency selectivity.
    Type: Grant
    Filed: April 28, 2009
    Date of Patent: January 15, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Mohammad M. Mansour, Sundeep Rangan, Siddharth Ray, Vincent Loncke, Pramod K. A. Rao, Joshua L. Koslov
  • Patent number: 8346829
    Abstract: Methods and apparatus which reduce or completely eliminate non-shift based divisions as part of estimating transmitted symbols and/or generating slicing parameters corresponding to two symbol transmission streams in a wireless communication system are described. A linear least squares error estimation filtering module performs symbol estimations and/or slicing parameter generation while avoiding non-shift based division operations. The linear least squares estimation module generates intermediate parameters, and implements equations which facilitate symbol estimation utilizing shift based divisions while avoiding non-shift based divisions.
    Type: Grant
    Filed: March 26, 2009
    Date of Patent: January 1, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Siddharth Ray, Sundeep Rangan
  • Patent number: 8340703
    Abstract: A multi-mode base station includes a transmit standby mode and an active mode. Transmit standby mode of base station operation is a low power/low interference level of operation as compared to active mode. In transmit standby mode at least some of the synchronization signaling such as pilot tone signaling is reduced in power level and/or rate with respect to the active mode. In transmit standby mode, the base station has no active state registered wireless terminals being serviced but may have some sleep state registered wireless terminals being serviced. Mode transitions from active to transmit standby may be in response to: a detected period of inactivity, scheduling information, base station mode change signals, and/or detected wireless terminal state transition. Mode transitions from transmit standby to active may be in response to: scheduling information, access signals, wake-up signals, hand-off signals, wireless terminal state change signals, and/or base station mode change signals.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: December 25, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Pablo Anigstein, Arnab Das, Sundeep Rangan
  • Patent number: 8320928
    Abstract: Systems and methodologies are described that facilitate scheduling uplink transmissions. For instance, a time sharing scheme can be utilized such that differing mobile devices can be scheduled to transmit during differing time slots; however, it is also contemplated that a static scheme can be employed. Pursuant to an illustration, an interference budget can be combined with a time varying weighting factor associated with a base station; the weighting factor can be predefined and/or adaptively adjusted (e.g., based upon a load balancing mechanism). Moreover, the weighted interference budget can be leveraged for selecting mobile devices for uplink transmission (e.g., based at least in part upon path loss ratios of the mobile devices). Further, disparate interference budgets can be utilized by differing channels of a sector at a particular time. Also, for example, a base station can assign a loading factor to be utilized by wireless terminal(s) for generating channel quality report(s).
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: November 27, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Xinzhou Wu, Sundeep Rangan, Prashanth Hande, Arnab Das, Junyi Li
  • Publication number: 20120294258
    Abstract: Certain aspects of the present disclosure relate to a technique of designing a Media Access Control (MAC) scheduler for uplink communication in high rate wireless data systems, such as Long Term Evolution (LTE) wireless communication systems.
    Type: Application
    Filed: July 24, 2012
    Publication date: November 22, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Siddharth Ray, Ritesh K. Madan, Ashwin Sampath, Sundeep Rangan, Arnab Das
  • Patent number: 8311143
    Abstract: Methods and apparatus for avoiding overflow and underflow conditions through the determination of appropriate scaling factors in signal estimation processing in a receiver are described. The receiver estimates transmitted symbols from one or more transmitter device antennas, while avoiding underflow and overflow conditions. A pilot based noise estimate and an estimated expected received signal power, corresponding to a transmit antenna, are used to generate an SNR corresponding to the transmit antenna. The generated SNR is used to determine, e.g., select from a fixed size set of predetermined scale factor values, a scale factor to be used for estimation processing associated with the transmit antenna. In some embodiments, the generated scaling factors are used by a fixed point processing linear least squares error estimation module. Scaling factor determination is performed at a rate which is slower than the rate at which symbols are received from a transmit antenna.
    Type: Grant
    Filed: March 16, 2009
    Date of Patent: November 13, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Siddharth Ray, Sundeep Rangan
  • Patent number: 8265019
    Abstract: Systems and methodologies are described that facilitate dynamically adjusting scheduling priorities in relation to a combination of delay sensitive flows with delay requirements and best effort flows. The systems and methodologies provide optimal and efficient techniques to enable real time adjustment and assignment of bandwidth for a combination of best effort flows and delay sensitive flows. In particular, the bandwidth allocation is adjusted for each data packet such that delay requirements are met and the remaining bandwidth can be assigned to best effort flows.
    Type: Grant
    Filed: October 30, 2008
    Date of Patent: September 11, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Ritesh K. Madan, Arnab Das, Sundeep Rangan, Siddharth Ray