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).

  • Publication number: 20100238901
    Abstract: Systems, apparatus, methods and computer program products are provided. In some embodiments, a method for facilitating interference management in an unplanned wireless communication system is provided. The method can include a non-serving base station obtaining information about a user equipment served by a serving base station; and determining signal information based, at least, in part, on the information. The method can also include the non-serving base station disallowing access to the user equipment due to restricted access rules for the non-serving base station. The method can also include the non-serving base station performing interference management of the user equipment served by the serving base station. The interference management can be performed based, at least, in part, on the determined signal information.
    Type: Application
    Filed: March 18, 2010
    Publication date: September 23, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Ashwin Sampath, Sundeep Rangan, Raja Sekhar Bachu
  • Publication number: 20100238888
    Abstract: Systems, apparatus, methods and computer program products are provided. In some embodiments, a method for facilitating interference management in an unplanned wireless communication system is provided. The method can include a non-serving base station synchronizing a non-serving base station downlink subframe to a serving base station downlink subframe, wherein the serving base station downlink subframe is transmitted from a serving base station to a user equipment served by the serving base station. The method can also include the non-serving base station decoding one or more control channel symbols of the serving base station downlink subframe; and determining information for performing interference management associated with the user equipment. The determined information can be based, at least, in part, on the decoded one or more control channel symbols of the serving base station downlink subframe.
    Type: Application
    Filed: March 18, 2010
    Publication date: September 23, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Ashwin Sampath, Sundeep Rangan, Raja Sekhar Bachu
  • Publication number: 20100240382
    Abstract: Systems, apparatus, methods and computer program products are provided. In some embodiments, a method for facilitating interference management in an unplanned wireless communication system is provided. The method can include a non-serving base station: determining information about a user equipment, wherein the user equipment is served by a serving base station; and employing determined information about the user equipment to perform interference management at a non-serving base station. The method can also include the non-serving base station synchronizing to the user equipment using information indicative of the uplink scrambling code for use by the user equipment and information indicative of uplink slot configurations being used by the user equipment. The method can also include the non-serving base station performing interference management on the user equipment served by the serving base station.
    Type: Application
    Filed: March 18, 2010
    Publication date: September 23, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Ashwin Sampath, Sundeep Rangan, Raja Sekhar Bachu
  • Publication number: 20100220626
    Abstract: Methods and apparatus for communicating transmission backlog information are described. Reporting control factors are utilized to expand reporting possibilities for a fixed bit size request report. At least one report control factor is determined as a function of channel quality information, power information, device capability information, and/or quality of service information. A transmission backlog report value is interpreted as a function of a reporting control factor. A wide range of quantization schemes for reporting transmission backlog information are facilitated corresponding to a small bit size report. A communications device can adaptively select a quantization request level closely matched to its current needs such as to provide an accurate representation of its current traffic channel resource needs.
    Type: Application
    Filed: May 12, 2010
    Publication date: September 2, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Arnab Das, Sundeep Rangan, Pablo Anigstein, Murari Srinivasan
  • Publication number: 20100211540
    Abstract: Techniques for efficiently sending reports in a wireless communication system are described. Reports may be sent repetitively in accordance with a reporting format. A terminal receives an assignment of a control channel used to send reports and determines a reporting format to use based on the assignment. The reporting format indicates a specific sequence of reports sent in specific locations of a control channel frame. The terminal generates a set of reports for each reporting interval and arranges the set of reports in accordance with the reporting format. The terminal repetitively sends a plurality of sets of reports in a plurality of reporting intervals. Reports may also be sent adaptively based on operating conditions. An appropriate reporting format may be selected based on the operating conditions of the terminal, which may be characterized by environment (e.g., mobility), capabilities, QoS, and/or other factors.
    Type: Application
    Filed: July 14, 2006
    Publication date: August 19, 2010
    Inventors: Arnab Das, Sundeep Rangan, Pablo Anigstein, Junyi Li, Sathyadev Venkata Uppala, Rajiv Laroia
  • Publication number: 20100190514
    Abstract: Methods and apparatus for efficient two-stage paging wireless communications systems are described. Wireless terminals are assigned to paging groups. A few first paging message information bits are modulated (using non-coherent modulation) into a first paging signal and communicated from a base station to wireless terminals. WTs wake-up, receive the first paging signal and quickly ascertain whether its paging group should expect a second paging signal, if so, the WT is operated to receive the second paging signal; otherwise, the WT goes back to sleep conserving power. The base station modulates (using coherent modulation) a number of second message information bits into a second paging signal and transmits the signal to WTs. From the information in first and second paging signals, a WT can determine that it is the paged WT and process the paging instructions. The intended paged WT can transmit an acknowledgement signal on a dedicated uplink resource.
    Type: Application
    Filed: March 31, 2010
    Publication date: July 29, 2010
    Applicant: QUALCOMM INCORPORATED
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Prashanth Hande
  • Publication number: 20100178942
    Abstract: Methods and apparatus for efficient two-stage paging wireless communications systems are described. Wireless terminals are assigned to paging groups. A few first paging message information bits are modulated (using non-coherent modulation) into a first paging signal and communicated from a base station to wireless terminals. WTs wake-up, receive the first paging signal and quickly ascertain whether its paging group should expect a second paging signal, if so, the WT is operated to receive the second paging signal; otherwise, the WT goes back to sleep conserving power. The base station modulates (using coherent modulation) a number of second message information bits into a second paging signal and transmits the signal to WTs. From the information in first and second paging signals, a WT can determine that it is the paged WT and process the paging instructions. The intended paged WT can transmit an acknowledgement signal on a dedicated uplink resource.
    Type: Application
    Filed: March 23, 2010
    Publication date: July 15, 2010
    Applicant: QUALCOMM INCORPORATED
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Prashanth Hande
  • Patent number: 7756548
    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: September 19, 2005
    Date of Patent: July 13, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Pablo Anigstein, Arnab Das, Sundeep Rangan
  • Publication number: 20100144282
    Abstract: Methods and apparatus for providing channel diversity to wireless terminals (WTs) in a manner that reduces the latency between the time a WT encounters satisfactory channel conditions are described. A plurality of communications channels with different physical characteristics are maintained in a cell by a base station (BS). Each WT monitors multiple channels and maintains multiple channel estimates at the same time so that rapid switching between channels is possible. Channel quality information is conveyed from each WT to the BS. The WT or BS selects a channel based on the measured channel quality. By supporting multiple channels and by introducing periodic variations into the channels in various embodiments, the time before a WT encounters a channel with good or acceptable channel conditions is minimized even if the WT does not change location. Multiple antennas are used at the BS to support numerous channels simultaneously, e.g., by controlling antenna patterns.
    Type: Application
    Filed: December 3, 2009
    Publication date: June 10, 2010
    Applicant: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan
  • Patent number: 7711377
    Abstract: Methods and apparatus for efficient two-stage paging wireless communications systems are described. Wireless terminals are assigned to paging groups. A few first paging message information bits are modulated (using non-coherent modulation) into a first paging signal and communicated from a base station to wireless terminals. WTs wake-up, receive the first paging signal and quickly ascertain whether its paging group should expect a second paging signal, if so, the WT is operated to receive the second paging signal; otherwise, the WT goes back to sleep conserving power. The base station modulates (using coherent modulation) a number of second message information bits into a second paging signal and transmits the signal to WTs. From the information in first and second paging signals, a WT can determine that it is the paged WT and process the paging instructions. The intended paged WT can transmit an acknowledgement signal on a dedicated uplink resource.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: May 4, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Prashanth Hande
  • Publication number: 20100041355
    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: Application
    Filed: October 26, 2009
    Publication date: February 18, 2010
    Applicant: QUALCOMM INCORPORATED
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan, Frank A. Lane, Prashanth Hande
  • Patent number: 7630339
    Abstract: Methods and apparatus for providing channel diversity to wireless terminals (WTs) in a manner that reduces the latency between the time a WT encounters satisfactory channel conditions are described. A plurality of communications channels with different physical characteristics are maintained in a cell by a base station (BS). Each WT monitors multiple channels and maintains multiple channel estimates at the same time so that rapid switching between channels is possible. Channel quality information is conveyed from each WT to the BS. The WT or BS selects a channel based on the measured channel quality. By supporting multiple channels and by introducing periodic variations into the channels in various embodiments, the time before a WT encounters a channel with good or acceptable channel conditions is minimized even if the WT does not change location. Multiple antennas are used at the BS to support numerous channels simultaneously, e.g., by controlling antenna patterns.
    Type: Grant
    Filed: January 23, 2004
    Date of Patent: December 8, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan
  • Patent number: 7610024
    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: November 21, 2005
    Date of Patent: October 27, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Murari Srinivasan, Frank A. Lane, Prashanth Hande
  • Publication number: 20090257351
    Abstract: Methods and apparatus related to communicating and/or using load information in support of decentralized traffic scheduling decisions are described. Individual wireless terminals corresponding to a peer to peer connection which desire to communicate traffic signals make transmitter yielding and/or receiver yielding decisions on a traffic slot by traffic slot basis. Loading information is used to intentionally skew transmitter yielding decisions in response to conditions and/or needs in the system. A link load weight value is generated based on intended transmitter loading related information and/or intended receiver loading related information. Traffic request parameters and/or link load weight values are communicated between wireless communications devices in request and/or request response signaling.
    Type: Application
    Filed: November 10, 2008
    Publication date: October 15, 2009
    Applicant: QUALCOMM Incorporated
    Inventors: Prashanth Hande, Xinzhou Wu, Sundeep Rangan
  • Publication number: 20090248770
    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: Application
    Filed: March 26, 2009
    Publication date: October 1, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Siddharth Ray, Sundeep Rangan
  • Publication number: 20090245442
    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: Application
    Filed: March 16, 2009
    Publication date: October 1, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Ray Siddharth, Sundeep Rangan
  • Publication number: 20090247107
    Abstract: A signal received via a plurality of antennas, and containing an interference component and a desired communication component, is processed to suppress the interference component. The interference component is suppressed based on an inverse of a spatial covariance matrix, which inverse is produced without performing a matrix inversion operation.
    Type: Application
    Filed: March 28, 2009
    Publication date: October 1, 2009
    Applicant: QUALCOMM INCORPORATED
    Inventors: Subhadeep P. Roy, Niranjan N. Ratnakar, Sundeep Rangan
  • Patent number: 7567791
    Abstract: Wireless terminal for use with a multi-mode base station that supports a transmit standby mode and an active mode is described. 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 from the wireless terminal, hand-off signals, etc.
    Type: Grant
    Filed: September 19, 2005
    Date of Patent: July 28, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Pablo Anigstein, Arnab Das, Sundeep Rangan
  • Patent number: 7558245
    Abstract: A method and apparatus for joint time and frequency synchronization for orthogonal frequency division multiplexing (OFDM) systems. A multitone pilot signal is sent in a designated OFDM symbol period. The receiver synchronizes to the pilot signal in a two-stage procedure. The first stage estimates the frequency offset coarsely with a frequency-domain correlation method and estimates the time offset with smoothed time-domain correlation. In a multipath channel, the smoothed time offset estimate is used to locate a cyclic prefix interval which captures the maximum total signal energy. The second stage improves the frequency estimate with a computationally efficient numerical optimization method.
    Type: Grant
    Filed: December 30, 2005
    Date of Patent: July 7, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Rajiv Laroia, Junyi Li, Sundeep Rangan, Hemanth T. Sampath
  • Publication number: 20090170430
    Abstract: System and method for providing a timestamp packetized data interface between an RF unit and a modem. According to one embodiment, the RF unit receives an inbound RF signal, processes and demodulates the inbound RF signal to generate samples, generates a timestamp indicative of when the inbound RF signal was received, packetizes and multiplexes the samples and the timestamp, and sends the multiplexed stream to the modem. The modem generates received data from the samples. If the received data type requires a response to be sent at a particular time, the modem generates symbols from responsive outbound data, generates a timestamp which indicates when the outbound data is to be transmitted, packetizes and multiplexes the symbols and the timestamp, and sends the multiplexed stream to the RF unit. The RF unit generates an outbound RF signal from the symbols, and transmits the outbound signal in accordance with the timestamp.
    Type: Application
    Filed: December 19, 2008
    Publication date: July 2, 2009
    Applicant: QUALCOMM Incorporated
    Inventors: Sundeep Rangan, Frank Lane