Patents by Inventor Vinh-Phuong Le

Vinh-Phuong Le 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: 7873367
    Abstract: Methods and systems are provided for determining the location of a first wireless device (e.g., a mobile unit) within a wireless network comprising a plurality of second wireless devices (e.g., access points). The method includes identifying an overlap area corresponding to the intersection of RF ranges for the one or more second wireless devices then computing a set of signal strength values, each associated with a measure of RF signal strength (e.g., RSSI) received by the plurality of second wireless devices from the first wireless device. A decision metric is evaluated for a plurality of locations within the overlap area based on the set of signal strength values. The location of the first wireless device is determined by selecting, from the plurality of locations, a location having the optimum value of the decision metric within the overlap area. The decision metric may utilize a minimum mean square error (MMSE) calculation.
    Type: Grant
    Filed: June 28, 2007
    Date of Patent: January 18, 2011
    Assignee: Symbol Technologies, Inc.
    Inventors: Ajay Malik, Vinh-Phuong Le, Mahender Vangati
  • Patent number: 7826862
    Abstract: Methods and systems are provided for determining the location of a first wireless device (e.g., a mobile unit) within a wireless network comprising a second wireless device (e.g., an access point). The method includes determining a signal strength contour associated with RF communication between the access point and the mobile unit, and adding a correction factor to the signal strength contour to produce a corrected signal strength contour, wherein the correction factor includes the sums of the differences between the transmit power and the antenna gain associated with the mobile unit and the access point. In an alternate scheme involving stored fingerprint data, a correction factor is introduced based on the differences between antenna gains and transmit power associated with the mobile unit under consideration and the mobile unit used for generating the fingerprint data. The systems and methods disclosed herein are applicable, for example, to networks operating in accordance with 802.
    Type: Grant
    Filed: June 28, 2007
    Date of Patent: November 2, 2010
    Assignee: Symbol Technologies, Inc.
    Inventors: Ajay Malik, Vinh-Phuong Le, Mahender Vangati
  • Publication number: 20090005064
    Abstract: Methods and systems are provided for determining the location of a first wireless device (e.g., a mobile unit) within a wireless network comprising a plurality of second wireless devices (e.g., access points). The method includes identifying an overlap area corresponding to the intersection of RF ranges for the one or more second wireless devices then computing a set of signal strength values, each associated with a measure of RF signal strength (e.g., RSSI) received by the plurality of second wireless devices from the first wireless device. A decision metric is evaluated for a plurality of locations within the overlap area based on the set of signal strength values. The location of the first wireless device is determined by selecting, from the plurality of locations, a location having the optimum value of the decision metric within the overlap area. The decision metric may utilize a minimum mean square error (MMSE) calculation.
    Type: Application
    Filed: June 28, 2007
    Publication date: January 1, 2009
    Applicant: SYMBOL TECHNOLOGIES, INC.
    Inventors: Ajay MALIK, Vinh-Phuong LE, Mahender VANGATI
  • Publication number: 20090005063
    Abstract: Methods and systems are provided for determining the location of a first wireless device (e.g., a mobile unit) within a wireless network comprising a second wireless device (e.g., an access point). The method includes determining a signal strength contour associated with RF communication between the access point and the mobile unit, and adding a correction factor to the signal strength contour to produce a corrected signal strength contour, wherein the correction factor includes the sums of the differences between the transmit power and the antenna gain associated with the mobile unit and the access point. In an alternate scheme involving stored fingerprint data, a correction factor is introduced based on the differences between antenna gains and transmit power associated with the mobile unit under consideration and the mobile unit used for generating the fingerprint data. The systems and methods disclosed herein are applicable, for example, to networks operating in accordance with 802.
    Type: Application
    Filed: June 28, 2007
    Publication date: January 1, 2009
    Applicant: SYMBOL TECHNOLOGIES, INC.
    Inventors: Ajay MALIK, Vinh-Phuong LE, Mahender VANGATI
  • Publication number: 20070254670
    Abstract: Described is a system and method for optimizing throughput in a wireless network. The method comprises providing a predetermined wireless bandwidth on a wireless communication channel to a plurality of wireless nodes. A bandwidth used by a selected wireless node is analyzed. When the bandwidth is outside of a predetermined threshold range, a predetermined action is executed to adjust the bandwidth utilized by the selected wireless node.
    Type: Application
    Filed: May 1, 2006
    Publication date: November 1, 2007
    Inventors: Dean Kawaguchi, Vinh-Phuong Le
  • Publication number: 20070159298
    Abstract: The present invention describes a system for interrogating or updating electronic shelf tags in a store or warehouse without the need for a complicated or expensive infrastructure. In the system, a single portable RFID device is carried by a worker to perform tasks such as organizing goods on the shelves of a store or a warehouse. As the worker traverses the aisles he may use the portable RFID device to scan each RFID tag as it comes within range. Through a wireless connection to a central controller on which pricing information is stored, the portable RFID device is able to verify that the information located in each RFID tag is correct. If the information is not correct, it can be updated with the correct information from the central controller. Alternatively, the RFID device may be self-contained and have all the correct pricing information stored on an internal memory.
    Type: Application
    Filed: January 3, 2006
    Publication date: July 12, 2007
    Inventors: Chris Zegelin, Vinh-Phuong Le
  • Publication number: 20070104157
    Abstract: Described is a method for locationing in a communications network. A wireless access point receives a signal corresponding to activity of a plurality of wireless devices on a predetermined bandwidth. The signal is processed to generate a plurality of subsignals using a predetermined signal processing procedure. An energy level of a particular subsignal of the plurality of subsignals is determined. A location of a corresponding wireless device is determined as a function of the energy level and a predetermined locationing procedure.
    Type: Application
    Filed: November 4, 2005
    Publication date: May 10, 2007
    Inventors: Dean Kawaguchi, Vinh-Phuong Le
  • Publication number: 20070099596
    Abstract: Described is a method for detecting activity on a frequency band. A wireless signal of a predetermined radio frequency band is received. The signal is processed into a plurality of subsignals, each subsignal corresponding to a particular radio frequency channel of the band. An energy level of the corresponding subsignal is determined, and, when the energy level is greater than a predetermined level, the corresponding channel is analyzed.
    Type: Application
    Filed: November 2, 2005
    Publication date: May 3, 2007
    Inventors: Kevin Prest, Vinh-Phuong Le
  • Publication number: 20070025287
    Abstract: Described is a method for determining an existence of a predetermined wireless network coverage condition. A wireless coverage map of a wireless network is generated as a function of a location of at least one access point and a first signal data collected at a plurality of locations within the network. The first signal data includes a first signal strength of a wireless signal communicated between the at least one access point and a wireless device. A second signal data is received. The second signal data includes a second signal strength of a further wireless signal communicated between one of the at least one access point and a further wireless device. The existence of the predetermined wireless network coverage condition is determined as a function of the second signal data and the wireless coverage map.
    Type: Application
    Filed: July 28, 2005
    Publication date: February 1, 2007
    Inventors: David Goren, Vinh-Phuong Le, Benjamin Bekritsky, Guang Zeng