Patents by Inventor Christina Vlachou

Christina Vlachou 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: 11402489
    Abstract: Embodiments are directed to passive multi-person location tracking utilizing signal polarization. An embodiment of a system includes multiple receivers, including a first receiver at a first location and a second receiver at a second location, each receiver including one or more receiver antennas to receive polarized radio signals; a transmitter located at a third location to transmit polarized radio signals, the transmitter including antennas for a first signal at a first polarization direction and a second signal at a second, different polarization direction; and a processing system to receive channel state information from each receiver, and to track a plurality of individuals utilizing the received channel state information, wherein the tracking of the plurality of individuals is based at least in part on analysis of a polarization parameter and a set of location parameters generated for each of multiple reflection paths based on the channel state information.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: August 2, 2022
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Sangki Yun, Kyu-Han Kim, Christina Vlachou
  • Patent number: 11202297
    Abstract: Systems and methods described herein provide a centralized solution for interference mitigation that focuses on efficient spectrum management. Wireless Access Points (APs) collect interference measurements for wireless channels and generate corresponding interferer airtime estimates. The APs also determine Packet Error Rates (PERs) for wireless client devices currently being served via the channels by the APs. The APs send the interferer airtime measurements and the PERs to a centralized controller. If an interferer airtime estimate and a PER for a particular channel satisfy predefined threshold conditions, the controller modifies an allocation of wireless bandwidth for an AP that is currently using the channel and sends a message to the AP indicating how the allocation has been modified.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: December 14, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Ioannis Pefkianakis, Kyu-Han Kim
  • Patent number: 11181628
    Abstract: Examples provide accurate localization of an object by using a network device. Examples include determining distances between transmitter and receiver antennas of a network device, transmitting, by the transmitter antenna, a wireless signal having a transmit power, receiving, by the receiver antennas, a reflected signal that reflects off of an object, receiving, by the receiver antennas, a static signal that does not reflect off of the object, and processing the static and reflected signals and determining the location of the object, based on the distances between the transmitter and the receiver antennas and the transmit power.
    Type: Grant
    Filed: October 31, 2018
    Date of Patent: November 23, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Sangki Yun, Kyu-Han Kim, Raghav Hampapur Venkatnarayan, Christina Vlachou
  • Patent number: 11153029
    Abstract: Embodiments are directed to interference-aware link-rate adaptation for wireless communication. An embodiment of a storage medium includes instructions to operations including receiving data regarding wireless signals received by an access point, the access point to provide Wi-Fi communication, the wireless signals being communicated in an unlicensed radio spectrum; performing spectral analysis of the received wireless signals to identify a channel of an LTE (Long-Term Evolution) signal; and upon determining that energy level of the LTE signal is below an energy detection (ED) level and that the channel is a primary Wi-Fi channel for the access point, adapting a link rate for the access point based on channel state information for the channel.
    Type: Grant
    Filed: July 3, 2019
    Date of Patent: October 19, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Patent number: 11076307
    Abstract: A method of adjusting a communication link of a client device of a wireless local area network is described. The method includes monitoring two or more communication links between two or more client devices and a network device in a wireless local area network. The two or more client devices including a first client device and a second client device. The method also includes detecting a degradation in a first communication link between the first client device and the network device. The communication link degradation is not detected in a second communication link between the second client device and the network device. The method further includes determining the degradation in the first communication link is caused at least in part by interference from cellular network communications.
    Type: Grant
    Filed: April 25, 2018
    Date of Patent: July 27, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Swetank Kumar Saha, Kyu-Han Kim
  • Patent number: 11051206
    Abstract: Example method includes receiving, at an access point (AP), a plurality of virtual reality (VR) data from each of a plurality untethered mobile devices associated with a multi-user VR environment, receiving, at the AP, an indication of an atomic data block size for data to be transmitted to one or more of the plurality of untethered mobile devices, reducing, by the AP and based on the indication, a transmission duration of a VR data block to be transmitted to one or more of the plurality of untethered mobile devices.
    Type: Grant
    Filed: October 31, 2018
    Date of Patent: June 29, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20210181332
    Abstract: Embodiments are directed to passive multi-person location tracking utilizing signal polarization. An embodiment of a system includes multiple receivers, including a first receiver at a first location and a second receiver at a second location, each receiver including one or more receiver antennas to receive polarized radio signals; a transmitter located at a third location to transmit polarized radio signals, the transmitter including antennas for a first signal at a first polarization direction and a second signal at a second, different polarization direction; and a processing system to receive channel state information from each receiver, and to track a plurality of individuals utilizing the received channel state information, wherein the tracking of the plurality of individuals is based at least in part on analysis of a polarization parameter and a set of location parameters generated for each of multiple reflection paths based on the channel state information.
    Type: Application
    Filed: December 17, 2019
    Publication date: June 17, 2021
    Inventors: Sangki Yun, Kyu-Han Kim, Christina Vlachou
  • Patent number: 11038741
    Abstract: Embodiments are directed to multi-user virtual reality over wireless networks. An embodiment of a storage medium includes instructions for receiving a request at a network device for a virtual reality (VR) operation, the VR operation to serve VR client devices utilizing a wireless communication network; obtaining statistics regarding the wireless communication network and the VR client devices, the statistics including data transmission rates and data transmission quality; exposing the statistics to a server to assist with optimization of the wireless communication network; and facilitating optimization of the wireless communication network for multi-user VR operation based at least in part on the statistics.
    Type: Grant
    Filed: October 1, 2019
    Date of Patent: June 15, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Patent number: 10998988
    Abstract: Examples include classifying high frequency radio signals. Some examples include receiving a fast Fourier transform (FFT) of a high frequency radio signal, determining a first signal strength at a first guard frequency bin, determining a second signal strength at a second guard frequency bin, and determining a third signal strength at a direct current carrier frequency bin. Examples also include classifying the high frequency radio signal based on the first signal strength, the second signal strength, and the third signal strength.
    Type: Grant
    Filed: October 2, 2019
    Date of Patent: May 4, 2021
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20210099334
    Abstract: Embodiments are directed to multi-user virtual reality over wireless networks. An embodiment of a storage medium includes instructions for receiving a request at a network device for a virtual reality (VR) operation, the VR operation to serve VR client devices utilizing a wireless communication network; obtaining statistics regarding the wireless communication network and the VR client devices, the statistics including data transmission rates and data transmission quality; exposing the statistics to a server to assist with optimization of the wireless communication network; and facilitating optimization of the wireless communication network for multi-user VR operation based at least in part on the statistics.
    Type: Application
    Filed: October 1, 2019
    Publication date: April 1, 2021
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20210006348
    Abstract: Embodiments are directed to interference-aware link-rate adaptation for wireless communication. An embodiment of a storage medium includes instructions to operations including receiving data regarding wireless signals received by an access point, the access point to provide Wi-Fi communication, the wireless signals being communicated in an unlicensed radio spectrum; performing spectral analysis of the received wireless signals to identify a channel of an LTE (Long-Term Evolution) signal; and upon determining that energy level of the LTE signal is below an energy detection (ED) level and that the channel is a primary Wi-Fi channel for the access point, adapting a link rate for the access point based on channel state information for the channel.
    Type: Application
    Filed: July 3, 2019
    Publication date: January 7, 2021
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Patent number: 10846042
    Abstract: Example method includes: rendering, by a network device, a plurality of frames for a multi-user Virtual Reality (VR) environment at a first quality and a second quality, storing, at the network device, the plurality of frames at the first quality and the second quality, transmitting, from the network device and to an untethered mobile device, a first frame of the plurality of frames at the first quality using Wi-Fi, determining, by the network device, that an available bandwidth to the untethered mobile device does not satisfy a threshold, and transmitting, by the network device and in response to determining, a subsequent frame at the second quality using Wi-Fi.
    Type: Grant
    Filed: October 31, 2018
    Date of Patent: November 24, 2020
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Xing Liu, Kyu-Han Kim
  • Patent number: 10771171
    Abstract: Examples include classifying high frequency radio signals. Some examples include receiving a fast Fourier transform (FFT) of a high frequency radio signal, determining a first signal strength at a first guard frequency bin, determining a second signal strength at a second guard frequency bin, and determining a third signal strength at a direct current carrier frequency bin. Examples also include classifying the high frequency radio signal based on the first signal strength, the second signal strength, and the third signal strength.
    Type: Grant
    Filed: September 28, 2017
    Date of Patent: September 8, 2020
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20200133610
    Abstract: Example method includes: rendering, by a network device, a plurality of frames for a multi-user Virtual Reality (VR) environment at a first quality and a second quality, storing, at the network device, the plurality of frames at the first quality and the second quality, transmitting, from the network device and to an untethered mobile device, a first frame of the plurality of frames at the first quality using Wi-Fi, determining, by the network device, that an available bandwidth to the untethered mobile device does not satisfy a threshold, and transmitting, by the network device and in response to determining, a subsequent frame at the second quality using Wi-Fi.
    Type: Application
    Filed: October 31, 2018
    Publication date: April 30, 2020
    Inventors: Christina Vlachou, Xing Liu, Kyu-Han Kim
  • Publication number: 20200137622
    Abstract: Example method includes receiving, at an access point (AP), a plurality of virtual reality (VR) data from each of a plurality untethered mobile devices associated with a multi-user VR environment, receiving, at the AP, an indication of an atomic data block size for data to be transmitted to one or more of the plurality of untethered mobile devices, reducing, by the AP and based on the indication, a transmission duration of a VR data block to be transmitted to one or more of the plurality of untethered mobile devices.
    Type: Application
    Filed: October 31, 2018
    Publication date: April 30, 2020
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20200132823
    Abstract: Examples provide accurate localization of an object by using a network device. Examples include determining distances between transmitter and receiver antennas of a network device, transmitting, by the transmitter antenna, a wireless signal having a transmit power, receiving, by the receiver antennas, a reflected signal that reflects off of an object, receiving, by the receiver antennas, a static signal that does not reflect off of the object, and processing the static and reflected signals and determining the location of the object, based on the distances between the transmitter and the receiver antennas and the transmit power.
    Type: Application
    Filed: October 31, 2018
    Publication date: April 30, 2020
    Inventors: Sangki Yun, Kyu-Han Kim, Raghav Hampapur Venkatnarayan, Christina Vlachou
  • Publication number: 20200107214
    Abstract: Systems and methods described herein provide a centralized solution for interference mitigation that focuses on efficient spectrum management. Wireless Access Points (APs) collect interference measurements for wireless channels and generate corresponding interferer airtime estimates. The APs also determine Packet Error Rates (PERs) for wireless client devices currently being served via the channels by the APs. The APs send the interferer airtime measurements and the PERs to a centralized controller. If an interferer airtime estimate and a PER for a particular channel satisfy predefined threshold conditions, the controller modifies an allocation of wireless bandwidth for an AP that is currently using the channel and sends a message to the AP indicating how the allocation has been modified.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 2, 2020
    Inventors: Christina Vlachou, Ioannis Pefkianakis
  • Patent number: 10608757
    Abstract: Examples include classifying high frequency radio signals. Some examples include receiving a fast Fourier transform (FFT) of a high frequency radio signal, determining a first signal strength at a first guard frequency bin, determining a second signal strength at a second guard frequency bin, and determining a third signal strength at a direct current carrier frequency bin. Examples also include classifying the high frequency radio signal based on the first signal strength, the second signal strength, and the third signal strength.
    Type: Grant
    Filed: September 28, 2017
    Date of Patent: March 31, 2020
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20200036458
    Abstract: Examples include classifying high frequency radio signals. Some examples include receiving a fast Fourier transform (FFT) of a high frequency radio signal, determining a first signal strength at a first guard frequency bin, determining a second signal strength at a second guard frequency bin, and determining a third signal strength at a direct current carrier frequency bin. Examples also include classifying the high frequency radio signal based on the first signal strength, the second signal strength, and the third signal strength.
    Type: Application
    Filed: October 2, 2019
    Publication date: January 30, 2020
    Inventors: Christina Vlachou, Kyu-Han Kim
  • Publication number: 20190335347
    Abstract: A method of adjusting a communication link of a client device of a wireless local area network is described. The method includes monitoring two or more communication links between two or more client devices and a network device in a wireless local area network. The two or more client devices including a first client device and a second client device. The method also includes detecting a degradation in a first communication link between the first client device and the network device. The communication link degradation is not detected in a second communication link between the second client device and the network device. The method further includes determining the degradation in the first communication link is caused at least in part by interference from cellular network communications.
    Type: Application
    Filed: April 25, 2018
    Publication date: October 31, 2019
    Inventors: Christina Vlachou, Swetank Kumar Saha, Kyu-Han Kim