Patents by Inventor Vikram Chandrasekhar

Vikram Chandrasekhar 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: 9066251
    Abstract: A method of managing Wi-Fi access points (APs) includes selecting between a global optimization and a local optimization of AP parameters based at least in part on one or more factors. The method includes causing a global optimization to be performed in the event that a global optimization is selected, the global optimization comprising: searching for adjustments to a first set of AP parameters that optimize an overall performance associated with a global region, the global region including a first set of APs. The method includes causing a local optimization to be performed in the event that a local optimization is selected, the local optimization comprising: searching for adjustments to a second set of AP parameters that optimize an overall performance associated with a localized region, the localized region including a second set of APs, wherein the second set of APs comprises a subset of the first set of APs.
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: June 23, 2015
    Assignee: wildfire.exchange, inc.
    Inventors: Ritesh K. Madan, Vikram Chandrasekhar, Andrea Goldsmith, Santhosh Krishna
  • Patent number: 9058347
    Abstract: A collection of content objects and a representative content object may be stored in a k-dimensional tree. In one embodiment, a method includes receiving a content object; constructing a first k-dimensional tree in response to determining a second k-dimensional tree is storing information corresponding to a number of content objects that is equal to a number of nodes of the second k-dimensional tree; storing information corresponding to the received content object as a node in the first k-dimensional tree; and moving information corresponding to a stored content object from of each node of the second k-dimensional tree to a corresponding node of the first k-dimensional tree, wherein the corresponding node of the first k-dimensional tree is identified based at least in part on content of the content object.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: June 16, 2015
    Assignee: Facebook, Inc.
    Inventor: Vikram Chandrasekhar
  • Patent number: 9060289
    Abstract: A method of configuring small cell base stations in a cellular network is disclosed. A constraint on a performance-related metric associated with at least a portion of the cellular network is received. In some embodiments, the constraint on the performance-related metric comprises a constraint on a performance-related metric associated with one or more macrocells. Measurement data from one or more small cell base stations is received via a control interface. One or more optimized values of one or more parameters associated with one or more small cell base stations are searched. The searching is based at least in part on the received measurement data and subject to the constraint on the performance-related metric associated with the at least a portion of the cellular network. The one or more optimized values of the one or more parameters to the associated small cell base stations are transmitted.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: June 16, 2015
    Assignee: wildfire.exchange, inc.
    Inventors: Vikram Chandrasekhar, Andrea Goldsmith, Santhosh Krishna, Ritesh K. Madan
  • Patent number: 9053191
    Abstract: In one embodiment, a method includes at time t2, determining a delta set of first objects representing a difference between a first set of first objects at time t1 and a second set of first objects at time t2; comparing the delta set of first objects with a set of second objects represented as a balanced k-dimensional tree; and identifying each second object whose content substantially matches content of at least one first object from the delta set of first objects.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: June 9, 2015
    Assignee: Facebook, Inc.
    Inventor: Vikram Chandrasekhar
  • Publication number: 20150146676
    Abstract: A base station selects a subset of at least one geographically separated antennas for each of the plurality of user equipments. The base station forms at least layer of data stream including modulated symbols, precedes the data stream via multiplication with the NT by preceding matrix where N is the number of said layers and NT is the number of transmit antenna elements and transmits the precoded layers of data stream to the user equipment via the selected geographically separated antennas. The base station signals the subset of the plurality of geographically separated antennas via higher layer Radio Resource Control or via, a down link grant mechanism. The base station optionally does not signal the subset of the plurality of geographically separated antennas to the corresponding mobile user equipment.
    Type: Application
    Filed: February 3, 2015
    Publication date: May 28, 2015
    Inventors: EKO ONGGOSANUSI, VIKRAM CHANDRASEKHAR, RUNHUA CHEN
  • Patent number: 9001756
    Abstract: A wireless transmission system included at least one user equipment and a base station. The base station is operable to form a downlink control information block, modulate the downlink control information, precode the modulated downlink control information, and transmit the precoded, modulated downlink control information on at least one demodulation reference signal antenna port to the at least one user equipment. The precoded, modulated downlink control information is mapped to a set of N1 physical resource block pairs in a subframe from an orthogonal frequency division multiplexing symbol T1 to and orthogonal frequency division multiplexing symbol T2.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: April 7, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Runhua Chen, Eko Onggosanusi, Vikram Chandrasekhar, Anthony Ekpenyong
  • Patent number: 8976773
    Abstract: In an embodiment, a wireless communication system (100, FIG. 1) includes one or more nodes (102-108) and one or more user equipments (UE) (110). A node may apply (502, FIG. 5) a cell-specific spreading code to a cell identifier, which indicates an identity of a cell (113, FIG. 1) serviced by the node. The node may insert (504, FIG. 5), into a frame (200, FIG. 2), at least one synchronization channel symbol, which corresponds to the spread cell identifier, and the node may transmit (506, FIG. 5) the frame over an air interface. A UE may receive (702, FIG. 7) a frame from the air interface. The UE may despread (708) the spread cell identifier, and acquire (712) a cell identifier corresponding to a particular cell.
    Type: Grant
    Filed: July 23, 2012
    Date of Patent: March 10, 2015
    Assignee: Apple Inc.
    Inventors: Ahsan U. Aziz, Vikram Chandrasekhar, James Wesley McCoy
  • Patent number: 8948293
    Abstract: A base station selects a subset of at least one geographically separated antennas for each of the plurality of user equipments. The base station forms at least layer of data stream including modulated symbols, precodes the data stream via multiplication with the NT-by-N precoding matrix where N is the number of said layers and NT is the number of transmit antenna elements and transmits the precoded layers of data stream to the user equipment via the selected geographically separated antennas. The base station signals the subset of the plurality of geographically separated antennas via higher layer Radio Resource Control or via a down link grant mechanism. The base station optionally does not signal the subset of the plurality of geographically separated antennas to the corresponding mobile user equipment.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: February 3, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Eko Onggosanusi, Vikram Chandrasekhar, Runhua Chen
  • Publication number: 20140334325
    Abstract: This invention sets conditions for user equipment responses to channel state indicator request in channel state information that may conflict.
    Type: Application
    Filed: June 24, 2014
    Publication date: November 13, 2014
    Inventors: Vikram Chandrasekhar, Runhua Chen, Anthony Edet Ekpenyong
  • Patent number: 8761062
    Abstract: This invention sets conditions for user equipment responses to channel state indicator request in channel state information that may conflict.
    Type: Grant
    Filed: January 11, 2012
    Date of Patent: June 24, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Vikram Chandrasekhar, Runhua Chen, Anthony Ekpenyong
  • Patent number: 8750887
    Abstract: This invention includes signaling schemes for communicating the PDSCH muting configuration from the eNodeB to its UEs so that they can measure inter-cell CSI if configured. The base station transmits to each served user equipment a number signal indicating a number of allowed muting configurations, parameters for each allowed muting configuration and an enable/disable signal. Each served user equipment mutes or does not mute a physical downlink shared channel according to one of the allowed muting configurations and the state of a corresponding bit of the enable/disable signal.
    Type: Grant
    Filed: July 18, 2011
    Date of Patent: June 10, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Vikram Chandrasekhar, Runhua Chen
  • Publication number: 20140067806
    Abstract: In one embodiment, a method includes at time t2, determining a delta set of first objects representing a difference between a first set of first objects at time t1 and a second set of first objects at time t2; comparing the delta set of first objects with a set of second objects represented as a balanced k-dimensional tree; and identifying each second object whose content substantially matches content of at least one first object from the delta set of first objects.
    Type: Application
    Filed: August 30, 2012
    Publication date: March 6, 2014
    Inventor: Vikram Chandrasekhar
  • Publication number: 20140067870
    Abstract: In one embodiment, an object is stored in a k-dimensional forest that has a plurality of k-dimensional trees and each k-dimensional tree has a different size. If the smallest k-dimensional tree in the k-dimensional forest is not full, then the object is stored as a specific node in the smallest k-dimensional tree. Otherwise, a first k-dimensional tree in the k-dimensional forest is located, which is the smallest k-dimensional tree in the k-dimensional forest that is capable of storing the first object, objects in one or more second k-dimensional trees from the k-dimensional forest that are smaller than the first k-dimensional tree, and objects currently in the first k-dimensional tree. The object is stored as a specific node in the first k-dimensional tree. In addition, the objects in the second k-dimensional trees are moved and stored as specific nodes in the first k-dimensional tree.
    Type: Application
    Filed: August 30, 2012
    Publication date: March 6, 2014
    Inventor: Vikram Chandrasekhar
  • Patent number: 8654734
    Abstract: This invention is a method of wireless communication using candidate multi-cell CSI-RS time-frequency patterns in the invention. This invention avoids collision with antenna ports 0, 1, 2 and 3 used for transmitting cell-specific reference signals and port 5 used for transmitting demodulation reference signals. This invention satisfies the nested property requirement. This invention avoids collision with DM-RS signal for extended cyclic prefix transmission as long as DMRS Rank is less than or equal to 2. For ranks greater than 2, this invention produces patterns that may collide with Rel. 10 DM-RS for extended CP. The invention includes alternative patterns obtained by relabeling and/or reshuffling the CSI-RS antenna port numbers while preserving identical time-frequency resources assigned to CSI-RS in the time-frequency grid.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: February 18, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Vikram Chandrasekhar, Eko N. Onggosanusi, Runhua Chen
  • Publication number: 20140036816
    Abstract: A method of dynamically adjusting Wi-Fi parameters of a plurality of access points (APs) is disclosed. Reports from the plurality of APs are received through an interface. A conflict graph is created by a processor. Creating the conflict graph includes creating a plurality of vertices of the conflict graph, each vertex corresponding to one of the plurality of APs. Creating the conflict graph further includes determining that there is a conflict between at least some of the pairs of APs based at least in part on the received reports. Creating the conflict graph includes connecting an edge between each of the at least some of the pairs of APs. The conflict graph is stored in a memory.
    Type: Application
    Filed: August 5, 2013
    Publication date: February 6, 2014
    Inventors: Ritesh K. Madan, Vikram Chandrasekhar, Andrea Goldsmith, Santhosh Krishna
  • Publication number: 20140036709
    Abstract: A method of detecting a hidden node is disclosed. Reports from a plurality of access points (APs) are received. The method includes determining that transmissions from a second AP are not detected by a first AP based on the received report from the first AP. The method includes determining that transmissions from a client associated with the first AP are detected by the second AP based on the received report from the second AP. The method further includes detecting that the second AP is a hidden node, wherein transmissions from the hidden node interfere with transmissions between the client and the first AP, and wherein the detection is based at least in part on the determination that transmissions from the second AP are not detected by the first AP and the determination that transmissions from the client associated with the first AP are detected by the second AP.
    Type: Application
    Filed: August 5, 2013
    Publication date: February 6, 2014
    Inventors: Ritesh K. Madan, Vikram Chandrasekhar, Andrea Goldsmith, Santhosh Krishna
  • Publication number: 20140036691
    Abstract: A method of managing Wi-Fi access points (APs) includes selecting between a global optimization and a local optimization of AP parameters based at least in part on one or more factors. The method includes causing a global optimization to be performed in the event that a global optimization is selected, the global optimization comprising: searching for adjustments to a first set of AP parameters that optimize an overall performance associated with a global region, the global region including a first set of APs. The method includes causing a local optimization to be performed in the event that a local optimization is selected, the local optimization comprising: searching for adjustments to a second set of AP parameters that optimize an overall performance associated with a localized region, the localized region including a second set of APs, wherein the second set of APs comprises a subset of the first set of APs.
    Type: Application
    Filed: August 5, 2013
    Publication date: February 6, 2014
    Inventors: Ritesh K. Madan, Vikram Chandrasekhar, Andrea Goldsmith, Santhosh Krishna
  • Publication number: 20140036859
    Abstract: This invention is a method of wireless communication between a base station and at least one user equipment. The base station signals a user equipment to produce a burst of a number of sounding reference signals having a predetermined burst duration. The user equipment sounds wireless channel to the base station via a burst of sounding reference signals having the predetermined burst duration. The base station schedules transmission of user equipment in time and frequency domain according to a CQI estimated from the received sounding reference signals.
    Type: Application
    Filed: January 11, 2011
    Publication date: February 6, 2014
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Anthony Ekpenyong, Vikram Chandrasekhar, Runhua Chen, Pierre Bertrand
  • Publication number: 20130281089
    Abstract: A method of configuring small cell base stations in a cellular network is disclosed. A constraint on a performance-related metric associated with at least a portion of the cellular network is received. In some embodiments, the constraint on the performance-related metric comprises a constraint on a performance-related metric associated with one or more macrocells. Measurement data from one or more small cell base stations is received via a control interface. One or more optimized values of one or more parameters associated with one or more small cell base stations are searched. The searching is based at least in part on the received measurement data and subject to the constraint on the performance-related metric associated with the at least a portion of the cellular network. The one or more optimized values of the one or more parameters to the associated small cell base stations are transmitted.
    Type: Application
    Filed: April 22, 2013
    Publication date: October 24, 2013
    Inventors: Vikram Chandrasekhar, Andrea Goldsmith, Santhosh Krishna, Ritesh K. Madan
  • Publication number: 20130272285
    Abstract: A method of managing Wi-Fi access points using a Wi-Fi network manager is disclosed. Measurement data is received from a plurality of Wi-Fi access points via a control interface. Optimized adjustments to one or more Wi-Fi parameters associated with one or more of the plurality of access points are searched based at least in part on a set of network optimization goals and the measurement data received from the plurality of access points. At least some of the optimized adjustments to the one or more Wi-Fi parameters are transmitted to the one or more of the plurality of access points using the control interface.
    Type: Application
    Filed: April 4, 2013
    Publication date: October 17, 2013
    Inventors: Andrea Goldsmith, Vikram Chandrasekhar, Ritesh K. Madan, Santhosh Krishna