Patents by Inventor Karthikeyan Sundaresan

Karthikeyan Sundaresan 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: 11971473
    Abstract: A product locating system is provided. The system includes at least one Radio Frequency (RF) backscatter transmitter configured to emit a main carrier RF signal that forms an excitation signal. The system further includes a passive RF backscatter tag associated with a product and configured to generate an Ultra-Wideband (UWB) signal from the excitation signal. The system also includes at least one RF backscatter receiver configured to simultaneously receive both the excitation signal from the at least one RF backscatter transmitter and the UWB signal from the passive RF backscatter tag, and compute the time-difference-of-arrival (TDoA) therebetween. TDoA information from multiple RF backscatter receivers, including the at least one RF backscatter receiver, is aggregated to compute the location of the product to which the passive RF backscatter tag is attached.
    Type: Grant
    Filed: January 25, 2021
    Date of Patent: April 30, 2024
    Assignee: NEC Corporation
    Inventors: Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20230345207
    Abstract: A method for assessing viability of a WiFi fine tune measurement (FTM) based ranging protocol for enterprise-grade localization with heterogeneity across operational parameters is presented. The method includes enabling a plurality of access points to range with a plurality mobile devices handled by a plurality of users within an enterprise environment, tracking a mobile device of the plurality of mobile devices using onboard sensors as the mobile device travels within the enterprise environment, measuring a plurality of ranges with at least three access points of the plurality of access points at various points along a trajectory, and combining information related to the plurality of ranges and the trajectory to predict a range offset of the mobile device such that the mobile device itself self-calibrates all its range offsets on-demand.
    Type: Application
    Filed: March 13, 2023
    Publication date: October 26, 2023
    Inventors: Ramanujan Sheshadri, Karthikeyan Sundaresan, Shivang Aggarwal
  • Patent number: 11620462
    Abstract: A method for product tagging is presented including emitting, by at least one RF backscatter transmitter, a dual-tone Radio Frequency (RF) signal embedded within a standardized RF signal on a frequency channel, reflecting and frequency shifting, by a passive RF backscatter tag associated with a product, the dual-tone RF signal to a different frequency channel, and reading, by at least one RF backscatter receiver, the product on the different frequency channel by detecting a distributed ambient backscatter signal generated by a reflection and frequency shifting of the dual-tone RF signal by the passive RF backscatter tag.
    Type: Grant
    Filed: March 16, 2021
    Date of Patent: April 4, 2023
    Assignee: NEC Corporation
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan, Mohammad Rostami
  • Patent number: 11595934
    Abstract: Methods and systems for localization within an environment include determining a topology estimate of nodes located in a dynamic indoor environment, based on distances measured between the nodes. Rigid k-core sub-graphs of the topology estimate are generated to determine relative localizations of the nodes. Relative localizations are transformed into absolute localizations to generate a map of positions of the nodes within the environment. A feature of the map is deployed to a device in the environment.
    Type: Grant
    Filed: March 26, 2021
    Date of Patent: February 28, 2023
    Inventors: Ayon Chakraborty, Karthikeyan Sundaresan, Sampath Rangarajan, Md. Shaifur Rahman
  • Publication number: 20220381870
    Abstract: Methods and systems for determining a device position include determining a first position estimate using radio-based range information. A second position estimate is determined using visual odometry information. The first position estimate and the second position estimate are fused based on radio environmental conditions and visual environmental conditions to determine a final position estimate. Resources are deployed based on the final position estimate.
    Type: Application
    Filed: May 26, 2022
    Publication date: December 1, 2022
    Inventors: Karthikeyan Sundaresan, Ramanujan Sheshadri, Mallesham Dasari
  • Publication number: 20220338158
    Abstract: Methods and systems for identifying device positions include measuring radio signal strength information between devices. Inertial information is measured for the devices. The radio signal strength information and the inertial information are fused to determine relative locations between the devices. The relative locations are oriented to a fixed anchor node. Elevation is estimated for the plurality of devices using pressure sensor information.
    Type: Application
    Filed: April 18, 2022
    Publication date: October 20, 2022
    Inventors: Ramanujan Sheshadri, Karthikeyan Sundaresan, Md. Shaifur Rahman
  • Publication number: 20220229187
    Abstract: A method is provided for beam management. The method includes obtaining, by a Light Detection and Radar (LiDAR) sensor having one or more LiDAR cameras performing ray-tracing, out-of-band infrared measurements of a surrounding environment. The method further includes selecting, by a base station, a transmission and reception beam pair for use in the surrounding environment from a plurality of available transmission and reception beam pairs responsive to the out-of-band measurements of the surrounding environment.
    Type: Application
    Filed: January 13, 2022
    Publication date: July 21, 2022
    Inventors: Eugene Chai, Karthikeyan Sundaresan, Mohammad Khojastepour, Timothy Woodford
  • Patent number: 11388564
    Abstract: Aspects of the present disclosure describe systems, methods, and structures infrastructure-free RF tracking in dynamic indoor environments.
    Type: Grant
    Filed: August 21, 2020
    Date of Patent: July 12, 2022
    Inventors: Ayon Chakraborty, Karthikeyan Sundaresan, Sampath Mateo Rangarajan, Md.Shaifur Rahman
  • Patent number: 11356172
    Abstract: Systems and methods implementing a multi-unmanned aerial vehicle (UAV) wireless communication network are provided. The system includes application UAVs that wirelessly provide applications. The system includes relay UAVs that connect the application UAVs to a ground station. The ground station connects to a wireless backhaul network. Processor devices determine mobility for the application UAVs based on application-specific objectives. The processor devices also determine mobility for the relay UAVs based on forming and maintaining the wireless backhaul network.
    Type: Grant
    Filed: March 12, 2020
    Date of Patent: June 7, 2022
    Inventors: Eugene Chai, Sampath Rangarajan, Karthikeyan Sundaresan, Ramanujan Sheshadri
  • Publication number: 20220103246
    Abstract: Systems and methods implementing a multi-unmanned aerial vehicle (UAV) wireless communication network are provided. The system includes application UAVs that wirelessly provide applications. The system includes relay UAVs that connect the application UAVs to a ground station. The ground station connects to a wireless backhaul network. Processor devices determine mobility for the application UAVs based on application-specific objectives. The processor devices also determine mobility for the relay UAVs based on forming and maintaining the wireless backhaul network.
    Type: Application
    Filed: March 12, 2020
    Publication date: March 31, 2022
    Inventors: Eugene Chai, Sampath Rangarajan, Karthikeyan Sundaresan, Ramanujan Sheshadri
  • Patent number: 11169518
    Abstract: Systems and methods for localizing and tracking mobile objects are provided. A method includes determining an initial location of a node in a multi-hop network based on multi-lateration from an unmanned aerial vehicle. The method also includes applying an adaptive aperture to address a non-uniform velocity of the node based on the turn and a velocity vector. A determination whether localization for the node can be implemented using first hop nodes in the multi-hop network is made. In response to a determination that localization cannot be implemented using the first hop nodes, inertial sensor measurements associated with the node are accessed and the inertial sensor measurements are integrated with the adaptive aperture to improve localization accuracy.
    Type: Grant
    Filed: April 22, 2020
    Date of Patent: November 9, 2021
    Inventors: Ayon Chakraborty, Karthikeyan Sundaresan, Sampath Rangarajan, Ashutosh Dhekne
  • Publication number: 20210311504
    Abstract: Systems and methods for automatically constructing a 3-dimensional (3D) model of a feature using a drone. The method includes generating a reconnaissance flight path that minimizes battery usage by the drone, and conducting a discovery flight that uses the reconnaissance flight path. The method further includes transmitting reconnaissance laser sensor data from the drone to a processing system for target identification, and selecting a target feature for 3D model construction based on the reconnaissance laser sensor data. The method further includes scanning the target feature using a laser sensor, transmitting laser sensor data for the target feature having a minimum point density from the drone to the processing system for 3D model construction, and constructing the 3D model from the minimum point density laser sensor data.
    Type: Application
    Filed: April 1, 2021
    Publication date: October 7, 2021
    Inventors: Eugene Chai, Karthikeyan Sundaresan, Sampath Rangarajan
  • Publication number: 20210306977
    Abstract: Methods and systems for localization within an environment include determining a topology estimate of nodes located in a dynamic indoor environment, based on distances measured between the nodes. Rigid k-core sub-graphs of the topology estimate are generated to determine relative localizations of the nodes. Relative localizations are transformed into absolute localizations to generate a map of positions of the nodes within the environment. A feature of the map is deployed to a device in the environment.
    Type: Application
    Filed: March 26, 2021
    Publication date: September 30, 2021
    Inventors: Ayon Chakraborty, Karthikeyan Sundaresan, Sampath Rangarajan, Md. Shaifur Rahman
  • Publication number: 20210294993
    Abstract: A method for product tagging is presented including emitting, by at least one RF backscatter transmitter, a dual-tone Radio Frequency (RF) signal embedded within a standardized RF signal on a frequency channel, reflecting and frequency shifting, by a passive RF backscatter tag associated with a product, the dual-tone RF signal to a different frequency channel, and reading, by at least one RF backscatter receiver, the product on the different frequency channel by detecting a distributed ambient backscatter signal generated by a reflection and frequency shifting of the dual-tone RF signal by the passive RF backscatter tag.
    Type: Application
    Filed: March 16, 2021
    Publication date: September 23, 2021
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan, Mohammad Rostami
  • Patent number: 11089432
    Abstract: Systems and methods for localizing and tracking mobile objects are provided. The method includes determining an initial location of a node based on multi-lateration from an unmanned aerial vehicle and determining a velocity vector associated with the node based on multi-lateration. The method also includes detecting when the node turns. An adaptive aperture is applied to address a non-uniform velocity of the node based on the turn and the velocity vector.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: August 10, 2021
    Inventors: Karthikeyan Sundaresan, Ayon Chakraborty, Sampath Rangarajan, Ashutosh Dhekne
  • Publication number: 20210231792
    Abstract: A product locating system is provided. The system includes at least one Radio Frequency (RF) backscatter transmitter configured to emit a main carrier RF signal that forms an excitation signal. The system further includes a passive RF backscatter tag associated with a product and configured to generate an Ultra-Wideband (UWB) signal from the excitation signal. The system also includes at least one RF backscatter receiver configured to simultaneously receive both the excitation signal from the at least one RF backscatter transmitter and the UWB signal from the passive RF backscatter tag, and compute the time-difference-of-arrival (TDoA) therebetween. TDoA information from multiple RF backscatter receivers, including the at least one RF backscatter receiver, is aggregated to compute the location of the product to which the passive RF backscatter tag is attached.
    Type: Application
    Filed: January 25, 2021
    Publication date: July 29, 2021
    Inventors: Karthikeyan Sundaresan, Sampath Rangarajan
  • Patent number: 11054843
    Abstract: A computer-implemented method, system, and computer program product are provided for positioning an unmanned autonomous vehicle (UAV) in a long term evolution radio access network. The method includes acquiring, by a processor-device, a position of the UAV with a global position system. The method also includes determining, by the processor-device, physical distances from the UAV to each of a plurality of user equipment (UE) responsive to a time-of-flight from the UAV to each of the plurality of UE. The method additionally includes generating, by the processor-device, radio environment maps for each of the plurality of UE with signal-to-noise ratios (SNR) from each of the plurality of UEs to the UAV. The method further includes selecting, by the processor-device, a determined position for the UAV as a position with a minimum SNR in the REMs. The method also includes commanding the UAV to move to the determined position.
    Type: Grant
    Filed: March 1, 2019
    Date of Patent: July 6, 2021
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan, Mohammad Khojastepour, Ayon Chakraborty
  • Publication number: 20210185491
    Abstract: Aspects of the present disclosure describe systems, methods, and structures infrastructure-free RF tracking in dynamic indoor environments.
    Type: Application
    Filed: August 21, 2020
    Publication date: June 17, 2021
    Applicant: NEC LABORATORIES AMERICA, INC
    Inventors: Ayon CHAKRABORTY, Karthikeyan SUNDARESAN, Sampath Mateo RANGARAJAN, Md.Shaifur RAHMAN
  • Publication number: 20210067899
    Abstract: Systems and methods for localizing and tracking mobile objects are provided. The method includes determining an initial location of a node based on multi-lateration from an unmanned aerial vehicle and determining a velocity vector associated with the node based on multi-lateration. The method also includes detecting when the node turns. An adaptive aperture is applied to address a non-uniform velocity of the node based on the turn and the velocity vector.
    Type: Application
    Filed: September 12, 2019
    Publication date: March 4, 2021
    Inventors: Karthikeyan Sundaresan, Ayon Chakraborty, Sampath Rangarajan, Ashutosh Dhekne
  • Patent number: 10936927
    Abstract: A product tagging system is provided. The product tagging system includes at least one RF backscatter transmitter configured to emit (i) a main carrier RF signal, and (ii) Radio Frequency (RF) signals on two frequencies whose summation forms a twin carrier RF signal. The product tagging system further includes a passive RF backscatter tag associated with a product and configured to reflect and frequency shift the main carrier RF signal to a different frequency using the twin carrier RF signal. The product tagging system also includes at least one RF backscatter receiver configured to read the product on the different frequency by detecting a distributed ambient backscatter signal generated by a reflection and frequency shifting of the main carrier RF signal by the passive RF backscatter tag.
    Type: Grant
    Filed: January 15, 2020
    Date of Patent: March 2, 2021
    Inventors: Karthikeyan Sundaresan, Eugene Chai, Sampath Rangarajan, Mohammad Rostami