Patents by Inventor Zhifeng Cai

Zhifeng Cai 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: 20240098527
    Abstract: This document describes improvements in range and reliability for wireless mesh networks implementing IEEE 802.11 networking technologies. Reducing the number of spatial streams, N, to a lower value at middle and far distance ranges using an optimized rate control algorithm, preemptively trades off a lower throughput limit for a higher link budget. This higher link budget provides longer range and higher RF link reliability by using an N×N spatial diversity of MIMO RF channels for maximizing link budget instead of network throughput.
    Type: Application
    Filed: February 4, 2022
    Publication date: March 21, 2024
    Applicant: Google LLC
    Inventors: Yu Wen, Zhifeng Cai, Srinivasa Kumar Duvvuri, Raymond Reynolds Hayes, Kevin N. Hayes, Der-Woei Wu
  • Patent number: 11688263
    Abstract: This document describes techniques and devices to detect and classify human and animal presence and/or motion based on changes in the interaction of the human or animal with Wireless Local Area Network (WLAN) radio frequency (RF) signals within or about a building structure, such as a home or office. A first WLAN device transmits a sounding packet to a second WLAN device and receives an acknowledgement (ACK) of receiving the sounding packet by the second WLAN device. The first WLAN device uses the received ACK to determine Channel State Information (CSI) for an RF signal path between the first WLAN device and the second WLAN device, aggregates the determined CSI with additional CSI, and uses the aggregated CSI to determine a presence or a motion within the structure.
    Type: Grant
    Filed: January 8, 2019
    Date of Patent: June 27, 2023
    Assignee: Google LLC
    Inventors: Dongeek Shin, Yu Wen, Zhifeng Cai, Brian Mitchell Silverstein, Raymond Reynolds Hayes, Kevin N. Hayes
  • Publication number: 20220005337
    Abstract: This document describes techniques and devices to detect and classify human and animal presence and/or motion based on changes in the interaction of the human or animal with Wireless Local Area Network (WLAN) radio frequency (RF) signals within or about a building structure, such as a home or office. A first WLAN device transmits a sounding packet to a second WLAN device and receives an acknowledgement (ACK) of receiving the sounding packet by the second WLAN device. The first WLAN device uses the received ACK to determine Channel State Information (CSI) for an RF signal path between the first WLAN device and the second WLAN device, aggregates the determined CSI with additional CSI, and uses the aggregated CSI to determine a presence or a motion within the structure.
    Type: Application
    Filed: January 8, 2019
    Publication date: January 6, 2022
    Applicant: Google LLC
    Inventors: Dongeek Shin, Yu Wen, Zhifeng Cai, Brian Mitchell Silverstein, Raymond Reynolds Hayes, Kevin N. Hayes
  • Patent number: 10791165
    Abstract: This document describes methods, devices, systems, and means for controlling wireless devices using aggregated data from cross-network access points. An access point (AP) provides operational information from a plurality of different types of client devices communicating with the AP to a cloud service and obtains per-client-device-type policy data from the cloud service that is based on aggregated operational information from a plurality of different types of client devices from different AP networks. The AP controls, using a wireless transceiver, a wireless client device that is of a first type, using the per-client-device-type policy data for the first type based on aggregated operational information from a plurality of different types of client devices from different AP networks.
    Type: Grant
    Filed: April 8, 2019
    Date of Patent: September 29, 2020
    Assignee: Google LLC
    Inventors: Ramya Bhagavatula, Srinivasa Kumar Duvvuri, Zhifeng Cai
  • Publication number: 20190312924
    Abstract: This document describes methods, devices, systems, and means for controlling wireless devices using aggregated data from cross-network access points. An access point (AP) provides operational information from a plurality of different types of client devices communicating with the AP to a cloud service and obtains per-client-device-type policy data from the cloud service that is based on aggregated operational information from a plurality of different types of client devices from different AP networks. The AP controls, using a wireless transceiver, a wireless client device that is of a first type, using the per-client-device-type policy data for the first type based on aggregated operational information from a plurality of different types of client devices from different AP networks.
    Type: Application
    Filed: April 8, 2019
    Publication date: October 10, 2019
    Applicant: Google LLC
    Inventors: Ramya Bhagavatula, Srinivasa Kumar Duvvuri, Zhifeng Cai
  • Patent number: 9872232
    Abstract: Methods, apparatuses, and devices are described for wireless communications in which neighborhood area network (NaN) information may be requested and provided in a relatively fast and efficient manner between devices of a NaN. A wireless communication device, such as a station in a wireless communications network, may transmit an active probe request to seek information related to a NaN. The active probe request may be a NaN specific probe request, or may be transmitted from a station as part of an active scan for wireless network infrastructure other than NaN devices (e.g., as part of a scan for an AP in a BSS). An AP or master device of the NaN may receive the probe request and generate a NaN discovery response, which may include information that the requesting device may use for connecting to a device in the NaN.
    Type: Grant
    Filed: October 17, 2014
    Date of Patent: January 16, 2018
    Assignee: QUALCOMM Incorporated
    Inventors: Ashish Kumar Shukla, Alireza Raissinia, Zhifeng Cai, Santosh Paul Abraham
  • Publication number: 20160183113
    Abstract: Mobile devices implement a ranging mechanism that includes a lead responder receiving ranging measurement requests from two different initiators in the same DW cycle. At the beginning of the DW cycle the lead responder broadcasts and/or publishes a channel availability map that includes a list of slots and channels in which to respond to the ranging measurement requests based on a number of ranging operations supported in each slot within the DW cycle and based on an autonomously determined response sequence. If the lead responder responds to all ranging requests by all initiators in a DW cycle, secondary responders can perform ranging in the same or subsequent DW cycles. Upon exhausting all initiators paired with the lead responder, a secondary responder becomes the “active” responder that is chosen based on a prioritization scheme that is universal among the group of devices in the ranging operation.
    Type: Application
    Filed: December 23, 2014
    Publication date: June 23, 2016
    Inventors: Praveen DUA, Zhifeng CAI, Meghna AGRAWAL, Andrew Mackinnon DAVIDSON, Samir KAPOOR, Amod BODAS
  • Patent number: 9286099
    Abstract: A method for balancing virtual machine loads is provided. The method comprises: monitoring load information of each of physical hosts and virtual machines operating on said physical hosts; calculating load index of each of said physical hosts and said virtual machines operating on said physical hosts respectively according to said load information; based on load index of each physical hosts, determining a source physical host on which any virtual machine needs to be migrated so as to reduce the load index of the source physical host; determining a target virtual machine to be migrated on the source physical host based on load index of each virtual machines on the source physical host and respective affinity factor indicating a degree of dependency of a virtual machine on a physical host on which it resides; and migrating the target virtual machine into a destination physical host different than the source physical host.
    Type: Grant
    Filed: November 22, 2012
    Date of Patent: March 15, 2016
    Assignee: HANGZHOU H3C TECHNOLOGIES CO., LTD.
    Inventor: Zhifeng Cai
  • Publication number: 20150293773
    Abstract: A method for use in a computer network comprises a proxy separately establishing a connection with a virtual machine VM running on a first server and establishing a connection with a client to enable the client to access the VM on the first server. Upon the proxy detecting a disconnection with the VM on the first server, it obtains information of a current position of the VM from a management platform, and, once the proxy obtains the information, if the information indicates that the VM is running on a second server, the proxy establishes a connection with the second server based on the obtained information so as to enable the client to access the VM on the second server.
    Type: Application
    Filed: October 28, 2013
    Publication date: October 15, 2015
    Inventors: Zhifeng Cai, Zhonghua Guo
  • Publication number: 20150156709
    Abstract: Methods, apparatuses, and devices are described for wireless communications in which neighborhood area network (NaN) information may be requested and provided in a relatively fast and efficient manner between devices of a NaN. A wireless communication device, such as a station in a wireless communications network, may transmit an active probe request to seek information related to a NaN. The active probe request may be a NaN specific probe request, or may be transmitted from a station as part of an active scan for wireless network infrastructure other than NaN devices (e.g., as part of a scan for an AP in a BSS). An AP or master device of the NaN may receive the probe request and generate a NaN discovery response, which may include information that the requesting device may use for connecting to a device in the NaN.
    Type: Application
    Filed: October 17, 2014
    Publication date: June 4, 2015
    Inventors: Ashish Kumar Shukla, Alireza Raissinia, Zhifeng Cai, Santosh Paul Abraham
  • Patent number: 9043636
    Abstract: A method of fencing in a cluster system including network devices and a management network device is disclosed. Each network device may run an application program and comprises a fence device. A first network device receives a fence operation command from the management network device. The fence operation command contains information of a target network device and information of a target application. The first network device may determine a fence device on the first network device that corresponds to the fence operation command and activates the determined fence device such that the fence device performs a fence operation on the target application program according to the fence operation command.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: May 26, 2015
    Assignee: HANGZHOU H3C TECHNOLOGIES CO., LTD.
    Inventor: Zhifeng Cai
  • Publication number: 20140229949
    Abstract: A method for balancing virtual machine loads is provided. The method comprises: monitoring load information of each of physical hosts and virtual machines operating on said physical hosts; calculating load index of each of said physical hosts and said virtual machines operating on said physical hosts respectively according to said load information; based on load index of each physical hosts, determining a source physical host on which any virtual machine needs to be migrated so as to reduce the load index of the source physical host; determining a target virtual machine to be migrated on the source physical host based on load index of each virtual machines on the source physical host and respective affinity factor indicating a degree of dependency of a virtual machine on a physical host on which it resides; and migrating the target virtual machine into a destination physical host different than the source physical host.
    Type: Application
    Filed: November 22, 2012
    Publication date: August 14, 2014
    Inventor: Zhifeng Cai
  • Patent number: 7363376
    Abstract: An apparatus and method for generating an identifier to facilitate delivery of enhanced data services in a wireless computing environment is presented. In accordance with one aspect of the invention, a method is presented comprising receiving a request to establish a communication session between a subscriber unit in a wireless communication system and a data network access server through a basestation, and selectively generating a communication session identifier to uniquely identify the communication session from a plurality of communication sessions supported by the network access server to enable mobility management within the point-to-point communication session between the basestation and the network access server.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: April 22, 2008
    Assignee: ArrayComm LLC
    Inventors: Christopher Uhlik, Neeraj Sinha, Zhifeng Cai
  • Patent number: 7339908
    Abstract: A system and related methods to facilitate the delivery of enhanced data services in a mobile wireless communications environment is generally described. According to one aspect of the invention, a data networking protocol is introduced generally comprising control commands and attribute-value pairs. The one or more control commands including one or more control commands selectively employed to establish, manage and tear-down a communication session by and between elements of a data network. The one or more attribute-value pair(s) (AVP), selectively employed by a network element to define one or more parameters of an accompanying control command, the AVPs including one or more mobility management AVPs to facilitate exchange of mobility information between at least a subset of the network elements of the data network participating in a point-to-point component of the communication session.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: March 4, 2008
    Assignee: ArrayComm, LLC.
    Inventors: Christopher Uhlik, Zhifeng Cai, Neeraj Sinha
  • Publication number: 20030026220
    Abstract: A system and related methods to facilitate the delivery of enhanced data services in a mobile wireless communications environment is generally described. According to one aspect of the invention, a data networking protocol is introduced generally comprising control commands and attribute-value pairs. The one or more control commands including one or more control commands selectively employed to establish, manage and tear-down a communication session by and between elements of a data network. The one or more attribute-value pair(s) (AVP), selectively employed by a network element to define one or more parameters of an accompanying control command, the AVPs including one or more mobility management AVPs to facilitate exchange of mobility information between at least a subset of the network elements of the data network participating in a point-to-point component of the communication session.
    Type: Application
    Filed: November 14, 2001
    Publication date: February 6, 2003
    Inventors: Christopher Uhlik, Zhifeng Cai, Neeraj Sinha
  • Publication number: 20030028649
    Abstract: An apparatus and method for generating an identifier to facilitate delivery of enhanced data services in a wireless computing environment is presented. In accordance with one aspect of the invention, a method is presented comprising receiving a request to establish a communication session between a subscriber unit in a wireless communication system and a data network access server through a basestation, and selectively generating a communication session identifier to uniquely identify the communication session from a plurality of communication sessions supported by the network access server to enable mobility management within the point-to-point communication session between the basestation and the network access server.
    Type: Application
    Filed: July 31, 2001
    Publication date: February 6, 2003
    Inventors: Christopher Uhlik, Neeraj Sinha, Zhifeng Cai