Patents by Inventor Mohammad Heidari

Mohammad Heidari 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: 10114123
    Abstract: The present disclosure relates to a method for determining the position of a WLAN positioning system (WPS) and satellite positioning system (SPS) enabled device. The method can include determining an initial WPS position of the device using WPS, calculating an error region around the initial WPS position of the device, dividing the error region into a plurality of points, obtaining satellite measurements from at least two satellites in view of the device, determining a variation in a receiver clock bias for each point within the error region based on the satellite measurements from at least two satellites, selecting the point with the lowest variation in the receiver clock bias, and determining whether or not to use the point with the lowest variation in receiver clock bias to refine the initial WPS position of the device.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: October 30, 2018
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Mohammad A. Heidari
  • Patent number: 10018151
    Abstract: Methods and apparatus to vary reverse thrust of aircraft engines are disclosed. An example cascade apparatus disclosed herein includes a cascade frame having a first end, a second end, and a fixed structure extending between the first end and second end, where the cascade frame defines a slot. A cascade forms a reverse thrust flow path and at least a portion of the cascade is slidably coupled to the frame via the slot. The cascade slides relative the frame between a first position to produce a first reverse thrust and a second position to produce a second reverse thrust, where the first reverse thrust is different than the second reverse thrust.
    Type: Grant
    Filed: January 14, 2015
    Date of Patent: July 10, 2018
    Assignee: The Boeing Company
    Inventors: Omid B. Nakhjavani, Anthony K. Gilbert, Andrew Na, Mohammad A. Heidari
  • Patent number: 9439041
    Abstract: In a system facilitating the calibration of a map-point grid for an indoor location determination, the grid includes several map points, each having a radio frequency (RF) data fingerprint being associated therewith. At least one of: (i) RF signal data from several RF sources, (ii) a user specified location indication, and (ii) tracking data from a sensor, the tracking data indicating a user's movement relative to a base map point, are received. The map-point grid is updated based on, at least in part, at least one of (i) adjusted RF data, the received RF data being adjusted using systematic analysis thereof, (ii) the tracking data, and (iii) the location indication. A user's location may be determined based on the fingerprints associated with the map-point grid, and sensor data.
    Type: Grant
    Filed: July 1, 2013
    Date of Patent: September 6, 2016
    Assignee: Lighthouse Signal Systems, LLC
    Inventors: Parviz Parvizi, Mohammad Heidari
  • Publication number: 20160201601
    Abstract: Methods and apparatus to vary reverse thrust of aircraft engines are disclosed. An example cascade apparatus disclosed herein includes a cascade frame having a first end, a second end, and a fixed structure extending between the first end and second end, where the cascade frame defines a slot. A cascade forms a reverse thrust flow path and at least a portion of the cascade is slidably coupled to the frame via the slot. The cascade slides relative the frame between a first position to produce a first reverse thrust and a second position to produce a second reverse thrust, where the first reverse thrust is different than the second reverse thrust.
    Type: Application
    Filed: January 14, 2015
    Publication date: July 14, 2016
    Inventors: Omid B. Nakhjavani, Anthony K. Gilbert, Andrew Na, Mohammad A. Heidari
  • Patent number: 8890746
    Abstract: Methods and systems of hybrid positioning are provided for increasing the reliability and accuracy of location estimation. According to embodiments of the invention, the quality of reported locations from specific sources of location is assessed. Satellite and non-satellite positioning systems provide initial positioning estimates. For each positioning system relevant information is collected and based on the collected information each system is assigned appropriate weight.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: November 18, 2014
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Mohammad A. Heidari
  • Publication number: 20140306842
    Abstract: The present disclosure relates to a method for determining the position of a WLAN positioning system (WPS) and satellite positioning system (SPS) enabled device. The method can include determining an initial WPS position of the device using WPS, calculating an error region around the initial WPS position of the device, dividing the error region into a plurality of points, obtaining satellite measurements from at least two satellites in view of the device, determining a variation in a receiver clock bias for each point within the error region based on the satellite measurements from at least two satellites, selecting the point with the lowest variation in the receiver clock bias, and determining whether or not to use the point with the lowest variation in receiver clock bias to refine the initial WPS position of the device.
    Type: Application
    Filed: January 27, 2014
    Publication date: October 16, 2014
    Applicant: Skyhook Wireless, Inc.
    Inventors: Farshid ALIZADEH-SHABDIZ, Mohammad A. HEIDARI
  • Publication number: 20140018095
    Abstract: In a system facilitating the calibration of a map-point grid for an indoor location determination, the grid includes several map points, each having a radio frequency (RF) data fingerprint being associated therewith. At least one of: (i) RF signal data from several RF sources, (ii) a user specified location indication, and (ii) tracking data from a sensor, the tracking data indicating a user's movement relative to a base map point, are received. The map-point grid is updated based on, at least in part, at least one of (i) adjusted RF data, the received RF data being adjusted using systematic analysis thereof, (ii) the tracking data, and (iii) the location indication. A user's location may be determined based on the fingerprints associated with the map-point grid, and sensor data.
    Type: Application
    Filed: July 1, 2013
    Publication date: January 16, 2014
    Inventors: Parviz Parvizi, Mohammad Heidari
  • Publication number: 20130162481
    Abstract: In a system facilitating the calibration of a map-point grid for an indoor location, the grid includes several map points, each having a radio frequency (RF) data fingerprint associated therewith. RF data are received from a device associated with a user, and a map point is identified or determined based on, at least in part, the received RF data. A reliability of a fingerprint to be associated with the map point is computed based on, at least in part, a comparison of a parameter associated with the map point with reference data associated with the indoor location such as topology of the location, and speed and orientation of the user. A fingerprint is associated with the first map point based on, at least in part, the first RF data and the computed reliability. The computation of the reliability may also be based on additional RF data and location determination based thereon and/or user feedback. An existing fingerprint may be adjusted based on the received RF data.
    Type: Application
    Filed: December 5, 2012
    Publication date: June 27, 2013
    Inventors: Parviz Parvizi, Mohammad Heidari
  • Patent number: 8350758
    Abstract: Systems and methods are disclosed herein for determining a user's location within an indoor environment. In particular, the system receives a location request including a set of radio frequency signal data collected by a mobile device inside of an indoor environment. Using this data set, the system first selects a map from a plurality of maps stored in a map database. The system then processes the data to identify the user's location on the selected map. The system uses yield information associated with the received signals in determining the map that the user is on, the user's location on the map, or both the map and the user's location to filter out transient signals and identify those signals that are reliably indicative of the user's location.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: January 8, 2013
    Assignee: Lighthouse Signal Systems LLC
    Inventors: Parviz Parvizi, Mohammad Heidari
  • Patent number: 8322038
    Abstract: A method for manufacturing a bearing housing comprising: selecting a configuration for housing and manufacturing the housing the configuration. The selected housing configuration comprises a bearing section and a base having a cylindrical shape. The bearing section and base are substantially aligned centrally along an axis. A plurality of members extends between the bearing section and the base. The plurality of members has a length and a width, and, in the configuration, each of the plurality of members has a side that is substantially non-perpendicular with respect to the bearing section and the base. At least one of the plurality of members extends at an angle from the bearing section to the base; the plurality of members having a curve relative to the axis; and the width of the plurality of members decreasing or increasing along the length of the plurality of members.
    Type: Grant
    Filed: April 20, 2009
    Date of Patent: December 4, 2012
    Assignee: The Boeing Company
    Inventors: Mohammad A. Heidari, Adrian Stanescu
  • Patent number: 8279114
    Abstract: The disclosed subject matter relates to a method for determining the position of a device in a hybrid positioning system. The method includes determining an initial position estimate of a device using a non-satellite positioning system, obtaining satellite measurements from less than four satellites, wherein the measurements include each satellite's position with respect to the initial position estimate, determining a dilution of precision (DOP) based on the satellite measurements, if the DOP is small, refining the initial position estimate using the satellite measurements, and if the DOP is large, providing the initial estimate as a final position estimate for the device. In some embodiments, the non-satellite positioning system is a WLAN positioning system. In some embodiments, the method includes obtaining satellite measurements from two satellites or three satellites.
    Type: Grant
    Filed: October 2, 2009
    Date of Patent: October 2, 2012
    Assignee: Skyhook Wireless, Inc.
    Inventors: Farshid Alizadeh-Shabdiz, Mohammad A. Heidari
  • Publication number: 20120112958
    Abstract: Methods and systems of hybrid positioning are provided for increasing the reliability and accuracy of location estimation. According to embodiments of the invention, the quality of reported locations from specific sources of location is assessed. Satellite and non-satellite positioning systems provide initial positioning estimates. For each positioning system relevant information is collected and based on the collected information each system is assigned appropriate weight.
    Type: Application
    Filed: November 3, 2011
    Publication date: May 10, 2012
    Inventors: Farshid ALIZADEH-SHABDIZ, Mohammad A. Heidari
  • Publication number: 20110080318
    Abstract: The disclosed subject matter relates to a method for determining a Dilution of Precision Metric (DOP) with less than four satellites in a hybrid positioning system. In some embodiments, the method includes determining an initial position estimate of a device using a non-satellite positioning system, obtaining satellite measurements from less than four satellites, wherein the measurements include each satellite's position with respect to the initial position estimate, constructing a geometry matrix corresponding to the measurements from the less than four satellites using each satellite's position and the initial position estimate, multiplying the geometry matrix by its transpose to construct an H matrix, determining an inverse of the H matrix, and determining the DOP based on a sum of the diagonal elements of the inverse H matrix. In some embodiments, the non-satellite positioning system is a WLAN positioning system.
    Type: Application
    Filed: October 2, 2009
    Publication date: April 7, 2011
    Applicant: SKYHOOK WIRELESS, INC.
    Inventors: Farshid ALIZADEH-SHABDIZ, Mohammad HEIDARI
  • Publication number: 20110080317
    Abstract: The disclosed subject matter relates to a method for determining the position of a device in a hybrid positioning system. The method includes determining an initial position estimate of a device using a non-satellite positioning system, obtaining satellite measurements from less than four satellites, wherein the measurements include each satellite's position with respect to the initial position estimate, determining a dilution of precision (DOP) based on the satellite measurements, if the DOP is small, refining the initial position estimate using the satellite measurements, and if the DOP is large, providing the initial estimate as a final position estimate for the device. In some embodiments, the non-satellite positioning system is a WLAN positioning system. In some embodiments, the method includes obtaining satellite measurements from two satellites or three satellites.
    Type: Application
    Filed: October 2, 2009
    Publication date: April 7, 2011
    Applicant: Skyhook Wireless, Inc.
    Inventors: Farshid ALIZADEH-SHABDIZ, Mohammad HEIDARI
  • Publication number: 20110074626
    Abstract: The present disclosure relates to a method for determining the position of a WLAN positioning system (WPS) and satellite positioning system (SPS) enabled device. The method can include determining an initial WPS position of the device using WPS, calculating an error region around the initial WPS position of the device, dividing the error region into a plurality of points, obtaining satellite measurements from at least two satellites in view of the device, determining a variation in a receiver clock bias for each point within the error region based on the satellite measurements from at least two satellites, selecting the point with the lowest variation in the receiver clock bias, and determining whether or not to use the point with the lowest variation in receiver clock bias to refine the initial WPS position of the device.
    Type: Application
    Filed: September 29, 2009
    Publication date: March 31, 2011
    Applicant: Skyhook Wireless, Inc.
    Inventors: Farshid ALIZADEH-SHABDIZ, Mohammad HEIDARI
  • Publication number: 20070024329
    Abstract: Embodiments of the present invention include circuits and methods for dividing signals. In one embodiment the present invention includes a divider circuit comprising at least one first divider input receiving an in-phase (I+) signal, at least one second divider input receiving a complement of the in-phase (I?) signal, at least one third divider input receiving a quadrature (Q+) signal, and at least one fourth divider input receiving a complement of the quadrature (Q?) signal. In one embodiment, the lock range of a divider is improved by providing a first bias current greater than a second bias current.
    Type: Application
    Filed: June 1, 2005
    Publication date: February 1, 2007
    Applicant: WiLinx, Inc.
    Inventors: Mohammad Heidari, Ahmad Mirzaei, Masoud Djafari, Rahim Bagheri
  • Publication number: 20070024330
    Abstract: Embodiments of the present invention include circuits and methods for dividing high frequency signals. In one embodiment the present invention includes a divider circuit comprising a differential circuit having first and second inputs to receive a first differential signal, a first frequency control input and first and second differential outputs, wherein the differential circuit has a first bias current. The divider circuit further includes a cross-coupled circuit having outputs coupled to the differential circuit outputs and a second frequency control input, wherein the cross-coupled circuit has a second bias current. Embodiments of the present invention may include circuits for controlling the relationship between bias currents and circuit parameters that vary with process or temperature or both.
    Type: Application
    Filed: June 1, 2005
    Publication date: February 1, 2007
    Applicant: WiLinx, Inc.
    Inventors: Ahmad Mirzaei, Mohammad Heidari, Masoud Djafari, Rahim Bagheri
  • Publication number: 20070026816
    Abstract: Embodiments of the present invention include a frequency synthesizer comprising a first plurality of dividers receiving a first signal having a first frequency and generating a first plurality of divided signals and a frequency combination network including a plurality of mixers, the frequency combination network receiving one or more of the first plurality of divided signals and generating a plurality of synthesized signals having different frequencies. The frequency combination network may further include additional dividers and multiplexers for more flexibility in synthesizing different frequencies. In one embodiment, the frequency combination network is coupled to dividers in the feedback path of a phase locked loop. The present invention is particularly advantageous for synthesizing frequencies above one (1) gigahertz.
    Type: Application
    Filed: June 1, 2005
    Publication date: February 1, 2007
    Applicant: WiLinx, Inc.
    Inventors: Mohammad Heidari, Ahmad Mizaei, Masoud Djafari, Mike Choi, Filipp Baron, Alireza Mehrnia, Rahim Bagheri
  • Patent number: 5172325
    Abstract: The invention described here provides a method for obtaining the "best" solution to balancing engine vibration where one or more corrective weights are applied to accessible stage of an engine, while other unbalanced stages remain inaccessible, and hence, no balancing weights can be applied there. The method involves placing balancing weights at accessible stages only, but taking into account vibration at such stages which is created by unbalances at the inaccessible stages. The method is practiced by calculating the angular limits for placing a corrective weight onto an engine stage, followed by calculating the minimum and maximum weight magnitude to be placed on the stage so that overall engine vibration remains below a certain desired level (D). Thereafter, the optimum weight and angular position is determined by minimizing D via a procedure of incremental calculations.
    Type: Grant
    Filed: August 2, 1990
    Date of Patent: December 15, 1992
    Assignee: The Boeing Company
    Inventor: Mohammad A. Heidari