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: 10375582
    Abstract: A mobile device transmits data over a shared spectrum in an uplink channel to a base station in a contention-based access scheme. The mobile device obtains data to be wirelessly transmitted over the shared spectrum in the uplink channel to the base station. The uplink channel is formatted with a frame/subframe structure with a predetermined timing. The mobile device determines whether the shared spectrum is free for transmission according to a listen before transmit procedure. When the shared spectrum is free for transmission, the mobile device contends with other mobile device to gain access to the uplink channel. After gaining access to the uplink channel, the mobile device transmits the data over the shared spectrum in the uplink channel to the base station.
    Type: Grant
    Filed: May 29, 2018
    Date of Patent: August 6, 2019
    Assignee: Cisco Technology, Inc.
    Inventors: Vikram Chandrasekhar, Kedar Shirali, Qing Zhao, Rajesh Pazhyannur
  • Publication number: 20190104489
    Abstract: A method of operating a base station (BS) for a coexistence operation in a wireless communication system is provided. The method comprises performing a first measurement of first signals received from neighbor BSs over channels that are shared with the neighbor BSs before receipt of a spectrum access grant from a network entity; generating a registration request comprising a first measurement report based on the first measurement of the first signals; transmitting, to the network entity, the registration request comprising the first measurement report of the first signals; receiving the spectrum access grant from the network entity; and performing a second measurement of second signals received from the neighbor BSs over the channels that are shared with the neighbor BSs after receiving the spectrum access grant from the network entity.
    Type: Application
    Filed: September 26, 2018
    Publication date: April 4, 2019
    Inventors: Pengda Huang, Hao Chen, Chance Tarver, Boon Loong Ng, Vikram Chandrasekhar, Jianzhong Zhang
  • Publication number: 20190069285
    Abstract: A UE includes a transceiver configured to receive, from a base station, a higher layer parameter that is set as enabled or disabled. The higher layer parameter is explicitly or implicitly determined to be disabled by Boolean parameters or DL DCI format types. The UE also includes a controller configured to, based on identifying that the higher layer parameter is set as enabled either on per CORESET basis or on per DCI format basis, assume that, for receiving a PDSCH, an indication state is present in a DL DCI transmitted by a PDCCH on a CORESET, wherein the indication state indicates an associated PDSCH QCL parameter. A transceiver receives the associated PDSCH using the QCL parameter from the base station.
    Type: Application
    Filed: August 7, 2018
    Publication date: February 28, 2019
    Inventors: Vikram Chandrasekhar, Boon Loong Ng, Young-Han Nam
  • Publication number: 20190021119
    Abstract: A method of a user equipment (UE) for control resource set (CORESET) configuration in a wireless communication system is provided. The method comprises receiving, from a base station (BS), system information, determining whether the system information includes a random access channel (RACH) CORESET configuration, determining a CORSET to use for transmitting data based on whether the RACH CORESET configuration is included in the system information, and receiving, from the BS, the data based on the determined CORESET over an RACH.
    Type: Application
    Filed: July 10, 2018
    Publication date: January 17, 2019
    Inventors: Boon Loong Ng, Young-Han Nam, Vikram Chandrasekhar
  • Patent number: 10171194
    Abstract: A system and method are provided wherein one or more femtocell base stations are deployed within a range of a cellular base station and utilize substantially the same frequency band as the cellular base station. Each femtocell base station may be configured to employ one or more interference avoidance techniques such that coexistence between the cellular and the corresponding femtocell base station is enabled. The interference avoidance techniques employed may include use of randomized time or frequency hopping; randomly selecting a predetermined number, or identifying one or more unutilized, frequency subchannels for signal transmission; using two or more transmit, and two or more receive antennas; nulling one or more transmissions in a direction of a nearby cellular base station user; handing off at least one cellular user to one of the femtocell base stations and vice versa; and/or reducing the transmission power of at least one femtocell base station.
    Type: Grant
    Filed: June 19, 2015
    Date of Patent: January 1, 2019
    Assignee: Board of Regents, The University of Texas System
    Inventors: Jeffrey G. Andrews, Vikram Chandrasekhar
  • Patent number: 10165589
    Abstract: An example method is provided in one example embodiment and includes receiving performance metric information from a plurality of small cell radios, wherein the performance metric information includes, at least in part, a number of user equipment that are to be scheduled on a first type and a second type of subframes for each small cell radio; determining resource allocation parameters for the plurality of small cell radios; exchanging interference information between two or more small cell radios of the plurality of small cell radios that includes an indication of whether a particular small cell radio is interfering with or is interfered by another small cell radio of the two or more small cell radios; and scheduling downlink resource transmissions on the first type and the second type of subframes for user equipment served by the two or more small cell radios.
    Type: Grant
    Filed: November 10, 2017
    Date of Patent: December 25, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ritesh K. Madan, Vikram Chandrasekhar, Rohit Umesh Nabar, Kedar Durgadas Shirali, Qing Zhao
  • Patent number: 10159048
    Abstract: A method is provided in one example embodiment and may include calculating, by one or more of a plurality of small cell radios, one or more sets of candidate power control parameters using a first interference constraint for uplink user equipment (UE) transmissions for UE served by the one or more of the plurality of small cell radios; determining, at a central management entity, whether an average of a sum of an expected interference for UE associated with the plurality of small cell radios violates a second interference constraint for any of the one or more sets of candidate power control parameters; and generating one or more messages for each of the plurality of small cell radios identifying one or more particular sets of power control parameters that provide for meeting the second interference constraint.
    Type: Grant
    Filed: June 17, 2017
    Date of Patent: December 18, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ritesh K. Madan, Rohit Umesh Nabar, Vikram Chandrasekhar, Kedar Durgadas Shirali, Qing Zhao
  • Patent number: 10154415
    Abstract: An example method is provided in one example embodiment and includes receiving at least one performance metric from each of a plurality of cells, the at least performance metric associated with a downlink transmission from the cell to one or more user equipment devices associated with the cell. The method further includes determining a fraction of resources for allocation within a fractional frequency reuse portion of a frequency spectrum based upon the received at least one performance metric, and determining a fraction of the resources for allocation within a reuse one portion of the frequency spectrum based upon the determined fraction of resources for allocation within the fractional frequency reuse portion of the frequency spectrum.
    Type: Grant
    Filed: August 4, 2015
    Date of Patent: December 11, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Ritesh K. Madan, Rohit Umesh Nabar, Vikram Chandrasekhar, Kedar Durgadas Shirali
  • Patent number: 10148337
    Abstract: A method of a user equipment (UE) for beam management in a wireless communication system is provided. The method comprises receiving, from a base station (BS), a radio resource control (RRC) signaling and a medium access control channel element (MAC CE) signaling including a beam indicator over a downlink channel for the beam management, identifying the beam indicator based on the RRC signaling and the MAC CE signaling, and determining the beam indicator for a physical downlink control channel (PDCCH), a common physical downlink shared channel (PDSCH), and a fallback unicast PDSCH.
    Type: Grant
    Filed: January 22, 2018
    Date of Patent: December 4, 2018
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Boon Loong Ng, Vikram Chandrasekhar, Young-Han Nam, Jaewon Kim
  • Publication number: 20180324678
    Abstract: Apparatuses and methods for synchronization signal (SS) block index and timing indication in wireless communication systems. A method of operating a user equipment (UE) includes receiving, from a base station (BS), sets of higher-layer configuration information. When configured for mobility measurement on SS and physical broadcast channel (PBCH) (SS/PBCH) blocks, the UE identifies, based on one of the sets of higher-layer configuration information, a first set of SS/PBCH blocks configured for the mobility measurement; and measures and reports mobility measurement quantities for the first set of SS/PBCH blocks. When configured for receiving a physical downlink shared channel (PDSCH), the UE identifies, based on another of the sets of higher-layer configuration information, a second set of SS/PBCH blocks configured for the UE; and receives the PDSCH with rate matching around a SS/PBCH block included in the second set of SS/PBCH blocks.
    Type: Application
    Filed: May 3, 2018
    Publication date: November 8, 2018
    Inventors: Hao Chen, Young-Han Nam, Chao He, Vikram Chandrasekhar, Hongbo Si, Boon Loong Ng
  • Publication number: 20180324607
    Abstract: A distributed Wi-Fi system includes a first Wi-Fi access point communicatively coupled to a modem/router for connectivity to the Internet and to a cloud controller via the Internet; and at least one additional Wi-Fi access point with wireless backhaul connections to the modem/router via the first Wi-Fi access point, wherein the first Wi-Fi access point and the at least one additional access point cooperatively form a single Wi-Fi network; wherein the cloud controller is configured to receive inputs related to operation of the single Wi-Fi network, perform an optimization based on the inputs with an objective function, and provide operational parameters for the single Wi-Fi network based on the optimization.
    Type: Application
    Filed: July 11, 2018
    Publication date: November 8, 2018
    Inventors: Balaji Rengarajan, William McFarland, Qinghai Gao, Andrea Goldsmith, Vikram Chandrasekhar, Ritesh K. Madan, Santhosh Krishna
  • Patent number: 10120889
    Abstract: In one embodiment, a method includes receiving a content object; and determining whether a list configured to store information of a pre-determined number of stored content objects is full. Each content object is represented as a vector of elements. The method also includes identifying a corresponding node of a k-dimensional tree for each of the stored content objects and the received content object based on determining one or more median vectors from the vectors of the content objects. Each node of the k-dimensional tree is configured to store the vector of a particular one of the content objects. The method also includes moving information corresponding to the vector of one or more of the stored content objects and the received content object from the list to the corresponding node of the k-dimensional tree.
    Type: Grant
    Filed: May 5, 2015
    Date of Patent: November 6, 2018
    Assignee: Facebook, Inc.
    Inventor: Vikram Chandrasekhar
  • Patent number: 10104689
    Abstract: A first wireless device determines the duration of a clear channel assessment interval based on feedback signals before transmitting data to a second wireless device. The first wireless device receives feedback signals, such as acknowledgement (ACK) and negative acknowledgement (NAK) signals, from one or more second wireless devices. The first wireless device determines a ratio of NAK/ACK signals in the feedback signals for a predetermined amount of time. The first wireless device determines whether the wireless medium is free by monitoring for wireless signals during a clear channel assessment interval. The duration of the clear channel assessment interval is based on the ratio of NAK/ACK signals. If the wireless medium is free for the duration of the clear channel assessment, the first wireless device wirelessly transmits data to at least one of the second wireless devices.
    Type: Grant
    Filed: March 1, 2016
    Date of Patent: October 16, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Rajesh Pazhyannur, Vikram Chandrasekhar, Raymond Yuk Chor Kwan
  • Publication number: 20180288625
    Abstract: A mobile device transmits data over a shared spectrum in an uplink channel to a base station in a contention-based access scheme. The mobile device obtains data to be wirelessly transmitted over the shared spectrum in the uplink channel to the base station. The uplink channel is formatted with a frame/subframe structure with a predetermined timing. The mobile device determines whether the shared spectrum is free for transmission according to a listen before transmit procedure. When the shared spectrum is free for transmission, the mobile device contends with other mobile device to gain access to the uplink channel. After gaining access to the uplink channel, the mobile device transmits the data over the shared spectrum in the uplink channel to the base station.
    Type: Application
    Filed: May 29, 2018
    Publication date: October 4, 2018
    Inventors: Vikram Chandrasekhar, Kedar Shirali, Qing Zhao, Rajesh Pazhyannur
  • Publication number: 20180262313
    Abstract: A method of user equipment (UE) is provided. The method comprises receiving, from a base station (BS), configuration information indicating one or more of first sets of CSI-RS configuration parameters; determining channel state information-reference signal (CSI-RS) resources per frequency in a wireless communication system including a plurality of cells; and determining the first sets of CSI-RS configuration parameters for the cells, respectively, each of the first sets of CSI-RS configuration parameters including a physical cell identifier for the respective cell.
    Type: Application
    Filed: March 6, 2018
    Publication date: September 13, 2018
    Inventors: Young-Han Nam, Hao Chen, Boon Loong Ng, Vikram Chandrasekhar
  • Publication number: 20180234145
    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: Application
    Filed: April 17, 2018
    Publication date: August 16, 2018
    Inventors: Eko Onggosanusi, Vikram Chandrasekhar, Runhua Chen
  • Publication number: 20180234146
    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: Application
    Filed: April 17, 2018
    Publication date: August 16, 2018
    Inventors: Eko Onggosanusi, Vikram Chandrasekhar, Runhua Chen
  • Publication number: 20180219606
    Abstract: A method of a user equipment (UE) for beam management in a wireless communication system is provided. The method comprises receiving, from a base station (BS), a radio resource control (RRC) signaling and a medium access control channel element (MAC CE) signaling including a beam indicator over a downlink channel for the beam management, identifying the beam indicator based on the RRC signaling and the MAC CE signaling, and determining the beam indicator for a physical downlink control channel (PDCCH), a common physical downlink shared channel (PDSCH), and a fallback unicast PDSCH.
    Type: Application
    Filed: January 22, 2018
    Publication date: August 2, 2018
    Inventors: Boon Loong Ng, Vikram Chandrasekhar, Young-Han Nam, Jaewon Kim
  • Patent number: 10033447
    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: February 3, 2015
    Date of Patent: July 24, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Eko Onggosanusi, Vikram Chandrasekhar, Runhua Chen
  • Patent number: 10028151
    Abstract: A mobile device obtains data to be wirelessly transmitted over a shared spectrum in an uplink channel to a base station. The uplink channel is formatted with a frame/subframe structure with a predetermined timing. The mobile device determines whether the shared spectrum is free for transmission according to a Listen Before Transmit procedure. When the shared spectrum is free for transmission, the mobile device selects a start time in the uplink channel that mitigates interference from other mobile devices in proximity to the mobile device. Beginning at the start time, the mobile device transmits the data over the shared spectrum in the uplink channel to the base station.
    Type: Grant
    Filed: August 3, 2016
    Date of Patent: July 17, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Vikram Chandrasekhar, Kedar Shirali, Qing Zhao, Rajesh Pazhyannur