Patents by Inventor Farshid Alizadeh-Shabdiz

Farshid Alizadeh-Shabdiz 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: 20110012784
    Abstract: The disclosed subject matter generally relates to hybrid positioning systems and methods, more specifically, systems and methods of integrating a wireless local area network (WLAN) based positioning system (WLAN-PS) and a satellite positioning system (SPS) to improve accuracy of location estimates by selecting the best set of measurements from both systems.
    Type: Application
    Filed: July 16, 2009
    Publication date: January 20, 2011
    Applicant: SKYHOOK WIRELESS, INC.
    Inventor: Farshid ALIZADEH-SHABDIZ
  • Publication number: 20110012780
    Abstract: The disclosed subject matter generally relates to hybrid positioning systems and methods and, more specifically, systems and methods of detecting moved WLAN assess points using a wireless local area network based positioning system (WLAN-PS) and a satellite-based positioning system (SPS) with at least two satellites measurement.
    Type: Application
    Filed: July 16, 2009
    Publication date: January 20, 2011
    Applicant: SKYHOOK WIRELESS, INC.
    Inventor: Farshid ALIZADEH-SHABDIZ
  • Patent number: 7856234
    Abstract: The invention features a method of estimating an expected error of a position estimate for use in a WLAN positioning system that estimates the position of a WLAN-enabled device. The WLAN-enabled device receives signals transmitted by a WLAN access point in range of the WLAN-enabled device. The method estimates the position of the WLAN-enabled device based on the received signals from the WLAN access point in range of the WLAN enabled device. The method also estimates an expected error of the position estimate based on characteristics of the WLAN access point in range of the WLAN enabled device, wherein the expected error predicts a relative accuracy of the position estimate.
    Type: Grant
    Filed: January 22, 2007
    Date of Patent: December 21, 2010
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Edward J. Morgan
  • Patent number: 7835754
    Abstract: A method for estimating the speed and bearing of a Wi-Fi enabled device using WLAN radio signals in a WLAN based location service is provided. A method used to estimate a speed of travel of a Wi-Fi enabled device comprises the Wi-Fi enabled device receiving signals transmitted by Wi-Fi access points in range of the Wi-Fi enabled device, and using the signals to estimate the speed of and/or direction of travel of the Wi-Fi enabled device.
    Type: Grant
    Filed: May 8, 2006
    Date of Patent: November 16, 2010
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Edward J. Morgan, Kaveh Pahlavan
  • Patent number: 7818017
    Abstract: A location beacon database and server, method of building location beacon database, and location based service using same. Wi-Fi access points are located in a target geographical area to build a reference database of locations of Wi-Fi access points. At least one vehicle is deployed including at least one scanning device having a GPS device and a Wi-Fi radio device and including a Wi-Fi antenna system. The target area is traversed in a programmatic route to avoid arterial bias. The programmatic route includes substantially all drivable streets in the target geographical area and solves an Eulerian cycle problem of a graph represented by said drivable streets. While traversing the target area, periodically receive the GPS coordinates of the GPS device.
    Type: Grant
    Filed: December 4, 2007
    Date of Patent: October 19, 2010
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Russel K. Jones, Edward J. Morgan, Michael G. Shean
  • Patent number: 7768963
    Abstract: Systems and methods of improving sampling of WLAN packet information to improve estimates of Doppler frequency of a WLAN positioning device. A device estimates the position of itself. The device includes a WLAN radio module for receiving WLAN signals transmitted by WLAN APs in range of said device, extraction logic for extracting information from said received WLAN signals to identify the WLAN APs, and logic to cooperate with a WLAN-based positioning system to estimate the position of the device based at least in part on the extracted information identifying the WLAN APs in the range of said device. The WLAN radio module includes logic for measuring multiple received signal strength indicator (RSSI) values for sufficiently long WLAN packets to increase the sampled rate of RSSI of WLAN packets from WLAN APs and to thereby improve an estimate of the Doppler frequency of said device.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: August 3, 2010
    Assignee: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Patent number: 7769396
    Abstract: A location beacon database and server, method of building location beacon database, and location based service using same. Wi-Fi access points are located in a target geographical area to build a reference database of locations of Wi-Fi access points. At least one vehicle is deployed including at least one scanning device having a GPS device and a Wi-Fi radio device and including a Wi-Fi antenna system. The target area is traversed in a programmatic route to avoid arterial bias. The programmatic route includes substantially all drivable streets in the target geographical area and solves an Eulerian cycle problem of a graph represented by said drivable streets. While traversing the target area, periodically receive the GPS coordinates of the GPS device.
    Type: Grant
    Filed: December 4, 2007
    Date of Patent: August 3, 2010
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Russel K. Jones, Edward J. Morgan, Michael G. Shean
  • Publication number: 20100052983
    Abstract: This disclosure describes systems and methods for maintaining clock bias accuracy in a hybrid positioning system. In some embodiments, the method to maintain the stability of an internal clock of an satellite positioning system receiver by using WLAN access points (APs) can include maintaining the internal clock accuracy of a satellite positioning system receiver by using one or more WLAN APs as a reference.
    Type: Application
    Filed: June 5, 2009
    Publication date: March 4, 2010
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090312036
    Abstract: The present disclosure relates to systems and methods for improving the accuracy of expected error estimations in hybrid cellular and WLAN location determination. In some embodiments, the method can include providing a WLAN based location estimate and an expected error estimate for the WLAN based location estimate, providing a cellular based location estimate and an expected error estimate for the cellular based location estimate, and determining the expected error of the location determination by evaluating the consistency of the cellular based location estimate to the WLAN based location estimate. In some embodiments, the location estimate with the lower expected error can be selected as the location determination of the WLAN and cellular enabled device. In some embodiments, the consistency of the estimates can include the distance between the cellular based location estimate and the WLAN based location estimate.
    Type: Application
    Filed: June 16, 2009
    Publication date: December 17, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090310585
    Abstract: The disclosed subject matter relates to a method and system for increasing the accuracy of a WLAN based position estimate using cellular positioning information. In some embodiments, the method can include determining a set of possible WLAN location solutions for a WLAN and cellular enabled device based on one or more WLAN access points, obtaining cellular measurements from at least one cell tower, and determining the best WLAN location solution from the set of possible WLAN location solutions using the cellular measurements. In one embodiment, the method can include using the cellular measurements from the at least one cell tower to provide a cellular based location estimate for the WLAN and cellular enabled device.
    Type: Application
    Filed: June 16, 2009
    Publication date: December 17, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090312035
    Abstract: The present disclosure relates to systems and methods for determining the location of a WLAN and cellular position system enabled device using a WLAN position estimate to select the best cellular positioning system location. The method can include estimating a position of the WLAN and cellular enabled device using a WLAN positioning system and an expected error estimate for the WLAN based position estimate, determining a set of possible cellular based position estimates for the WLAN and cellular enabled device using cellular measurements obtained from at least one cell tower, determining an uncertainty area around the WLAN location estimate based on the expected error of the WLAN location estimate, and determining the device location by selecting cellular based location estimates located within the uncertainty area.
    Type: Application
    Filed: June 16, 2009
    Publication date: December 17, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090303119
    Abstract: This disclosure describes systems and methods for using environmental information in a hybrid positioning system. Some embodiments relate to a method for determining the position of a WLAN and satellite positioning system enabled device using characteristics of the environment in which the device is located, the method can include detecting WLAN APs in range of the device, obtaining environmental characteristics from a reference database based on the WLAN APs detected by the device, and determining whether to use the WLAN or satellite positioning system based on the environmental characteristics.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090303120
    Abstract: This disclosure describes a method and system for determining position using a WLAN-PS estimated position as an initial position. In some embodiments, the method can include calculating a WLAN position estimate of the WLAN and satellite enabled device and using the WLAN position estimate as an initial position in satellite position system to determine the location of the WLAN and satellite enabled device.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090303115
    Abstract: This disclosure describes methods and systems for stationary user detection in a hybrid location system. In some embodiments, the method for determining whether a satellite enabled device is stationary by measuring the Doppler frequency of received satellite signals can include acquiring satellite measurements from at least two satellites, wherein the satellite measurements include Doppler frequency measurements, acquiring a rough estimate of location of the satellite enabled device and calculating an internal frequency offset of satellite enabled device.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090303121
    Abstract: This disclosure describes a system and method for using a satellite positioning system to filter WLAN access points in a hybrid positioning system. In some embodiments, the method can include detecting WLAN APs in range of the WLAN and satellite enabled device, obtaining satellite measurements from at least two satellites to provide a plurality of possible satellite locations of the device, and providing a weight for each AP based on the distance from the WLAN APs to the possible satellite locations of the device.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid ALIZADEH-SHABDIZ
  • Publication number: 20090303112
    Abstract: This disclosure describes a system and method for refining a WLAN-PS estimated location using satellite measurements. In some embodiments, the disclosure relates to a method of determining the location of a WLAN and satellite enabled device by using two or more satellite measurements to refine an initial WLAN based location determination. The method can include estimating a position of the WLAN and satellite enabled device using a WLAN positioning system, gathering satellite location measurements from at least two satellites, determining an uncertainty area around the WLAN location estimate based on the expected error of the WLAN location estimate, wherein the uncertainty area has a plurality of possible location solutions, and determining the device location estimate inside the WLAN location uncertainty that best satisfies the satellite measurements.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090303113
    Abstract: This disclosure describes methods and systems for improving the accuracy of expected error estimation in a hybrid positioning system. In some embodiments, the method of determining an expected error in a location determination of a WLAN and satellite enabled device can include determining a WLAN location estimate and an expected error estimate for the WLAN location estimate, obtaining measurements from at least two satellites, and determining the expected error of the location determination by evaluating the consistency of the satellite positioning system measurements to the WLAN positioning system location estimation.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090303114
    Abstract: This disclosure describes a method and system for determining location using a hybrid satellite and WLAN positioning system by selecting the best WLAN-PS solution. In some embodiments, the method of increasing the accuracy of a WLAN based position estimate using satellite positioning information can include determining a set of possible WLAN location solutions for a WLAN and satellite enabled device based on one or more WLAN access points, obtaining satellite information for the WLAN and satellite enabled device from at least two different satellites, and using the satellite information from the at least two different satellites to determine the best WLAN location solution from the set of possible WLAN location solutions.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 10, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventor: Farshid Alizadeh-Shabdiz
  • Publication number: 20090252138
    Abstract: A method for estimating the speed and bearing of a Wi-Fi enabled device using WLAN radio signals in a WLAN based location service is provided. A method used to estimate a speed of travel of a Wi-Fi enabled device comprises the Wi-Fi enabled device receiving signals transmitted by Wi-Fi access points in range of the Wi-Fi enabled device, and using the signals to estimate the speed of and/or direction of travel of the Wi-Fi enabled device.
    Type: Application
    Filed: June 18, 2009
    Publication date: October 8, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Kaveh Pahlavan, Edward J. Morgan
  • Publication number: 20090175189
    Abstract: Methods and systems for classifying WLAN access points according to the quality of estimation of characteristics of the WLAN access points are provided. The classifications may be used to scale a reference database and quantify an expected error of estimation of the characteristics of the access points. WLAN access points may be classified based on their impact on a user's position, speed of travel, and direction of travel estimation accuracy in a WLAN positioning system. A method for determining a quality of estimation of characteristics of a Wi-Fi access point comprises a Wi-Fi enabled scanning device measuring a number of received signal strength (RSS) samples of the Wi-Fi signal transmitted by the Wi-Fi access point. A total distance traveled by the Wi-Fi enabled scanning device while measuring the number of RSS samples is estimated and used to estimate the quality of estimation of characteristics of the Wi-Fi access point.
    Type: Application
    Filed: March 16, 2009
    Publication date: July 9, 2009
    Applicant: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Kaveh Pahlavan, Nicolas Brachet