Patents by Inventor Hamid Hemmati

Hamid Hemmati 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: 11542040
    Abstract: The disclosed method for a communication satellite may include (1) simultaneously generating a first transmission beam to a first ground station and a second transmission beam to each of a plurality of second ground stations in sequence according to a schedule, (2) simultaneously receiving a third transmission beam from the first ground station and a fourth transmission beam from each of the second ground stations in sequence according to the schedule, (3) forwarding first data received via the third transmission beam to each of the second ground stations via the second transmission beam, and (4) forwarding second data received via the fourth transmission beam from each of the second ground stations to the first ground station via the first transmission beam. Various other methods and systems are also disclosed.
    Type: Grant
    Filed: November 6, 2019
    Date of Patent: January 3, 2023
    Assignee: Meta Platforms, Inc.
    Inventor: Hamid Hemmati
  • Patent number: 10986381
    Abstract: In one embodiment, a method includes accessing multiple temporally synchronized video streams from multiple cameras operated by a first user. At least one of the cameras is a wireless camera worn on the first user's hand. The video streams are stitched together for presentation to one or more second users. The video streams as stitched together are provided for presentation to one or more second users.
    Type: Grant
    Filed: November 22, 2019
    Date of Patent: April 20, 2021
    Assignee: FACEBOOK, INC.
    Inventors: Hamid Hemmati, Shauhwa Cuan
  • Patent number: 10914052
    Abstract: The disclosed systems for laying underground fiber optic cable may include a drive body, at least one rotational motor, a forward auger element rotatably coupled to the drive body and positioned to be rotated by the at least one rotational motor in a first rotational direction, and a rear auger element rotatably coupled to the drive body and positioned to be rotated by the at least one rotational motor in a second, opposite rotational direction. Various other systems, methods, and devices are also disclosed.
    Type: Grant
    Filed: July 21, 2020
    Date of Patent: February 9, 2021
    Assignee: Facebook, Inc.
    Inventors: Hamid Hemmati, Hamidreza Bolandhemmat
  • Publication number: 20210025128
    Abstract: The disclosed systems for laying underground fiber optic cable may include a drive body, at least one rotational motor, a forward auger element rotatably coupled to the drive body and positioned to be rotated by the at least one rotational motor in a first rotational direction, and a rear auger element rotatably coupled to the drive body and positioned to be rotated by the at least one rotational motor in a second, opposite rotational direction. Various other systems, methods, and devices are also disclosed.
    Type: Application
    Filed: July 21, 2020
    Publication date: January 28, 2021
    Inventors: Hamid Hemmati, Hamidreza Bolandhemmat
  • Patent number: 10594389
    Abstract: Particular embodiments may provide a transceiver in geosynchronous orbit. The transceiver may include a plurality of forward channel receivers. At least one of the forward channel receivers may receive (1) a forward channel laser communication beam transmitted from a ground station and (2) an E-band frequency having a bandwidth of 81-86 GHz. The transceiver may also include a plurality of forward channel transmitters having different frequencies. The forward channel transmitters may transmit user beams to endpoint devices, wherein the user beams are derived from the forward channel laser and MMW communication beams. The transceiver may also include a plurality of return channel receivers, wherein the return channel receivers receive user beams from the endpoint devices. The transceiver may also include at least one return channel transmitter, wherein the return channel transmitter transmits a return channel laser communication beam to a ground station.
    Type: Grant
    Filed: May 21, 2019
    Date of Patent: March 17, 2020
    Assignee: Facebook, Inc.
    Inventors: Hamid Hemmati, Abhishek Tiwari
  • Patent number: 10523976
    Abstract: In one embodiment, a method includes accessing multiple temporally synchronized video streams from multiple cameras operated by a first user. At least one of the cameras is a wireless camera worn on the first user's hand. The video streams are stitched together for presentation to one or more second users. The video streams as stitched together are provided for presentation to one or more second users.
    Type: Grant
    Filed: January 9, 2018
    Date of Patent: December 31, 2019
    Assignee: FACEBOOK, INC.
    Inventors: Hamid Hemmati, Shauhwa Cuan
  • Publication number: 20190363783
    Abstract: Particular embodiments may provide a transceiver in geosynchronous orbit. The transceiver may include a plurality of forward channel receivers. At least one of the forward channel receivers may receive (1) a forward channel laser communication beam transmitted from a ground station and (2) an E-band frequency having a bandwidth of 81-86 GHz. The transceiver may also include a plurality of forward channel transmitters having different frequencies. The forward channel transmitters may transmit user beams to endpoint devices, wherein the user beams are derived from the forward channel laser and MMW communication beams. The transceiver may also include a plurality of return channel receivers, wherein the return channel receivers receive user beams from the endpoint devices. The transceiver may also include at least one return channel transmitter, wherein the return channel transmitter transmits a return channel laser communication beam to a ground station.
    Type: Application
    Filed: May 21, 2019
    Publication date: November 28, 2019
    Inventors: Hamid Hemmati, Abhishek Tiwari
  • Patent number: 10411829
    Abstract: Systems and methods for optical communication through air or space are disclosed. A method includes encoding one or more data frames with a data-link layer forward error correction (FEC) code to produce a plurality of encoded data frames and transmitting the plurality of encoded data frames from a transmitter (TX) to a receiver (RX) at least partially through air or space using a plurality of optical beams. The RX identifies a corrupted encoded data frame and reconstructs the corrupted encoded data frame using a data-link layer FEC decoder operating over a plurality of non-corrupted encoded data frames.
    Type: Grant
    Filed: August 17, 2015
    Date of Patent: September 10, 2019
    Assignee: Facebook, Inc.
    Inventors: Kevin Michael Birnbaum, Kevin Jerome Quirk, Hamid Hemmati, Chien-Chung Chen, Gary Mak
  • Patent number: 10374696
    Abstract: Particular embodiments may provide a transceiver in geosynchronous orbit. The transceiver may include a plurality of forward channel receivers. At least one of the forward channel receivers may receive (1) a forward channel laser communication beam transmitted from a ground station and (2) an E-band frequency having a bandwidth of 81-86 GHz. The transceiver may also include a plurality of forward channel transmitters having different frequencies. The forward channel transmitters may transmit user beams to endpoint devices, wherein the user beams are derived from the forward channel laser and MMW communication beams. The transceiver may also include a plurality of return channel receivers, wherein the return channel receivers receive user beams from the endpoint devices. The transceiver may also include at least one return channel transmitter, wherein the return channel transmitter transmits a return channel laser communication beam to a ground station.
    Type: Grant
    Filed: December 28, 2017
    Date of Patent: August 6, 2019
    Assignee: Facebook, Inc.
    Inventors: Hamid Hemmati, Abhishek Tiwari
  • Publication number: 20190215544
    Abstract: In one embodiment, a method includes accessing multiple temporally synchronized video streams from multiple cameras operated by a first user. At least one of the cameras is a wireless camera worn on the first user's hand. The video streams are stitched together for presentation to one or more second users. The video streams as stitched together are provided for presentation to one or more second users.
    Type: Application
    Filed: January 9, 2018
    Publication date: July 11, 2019
    Inventors: Hamid Hemmati, Shauhwa Cuan
  • Publication number: 20180191428
    Abstract: Particular embodiments may provide a transceiver in geosynchronous orbit. The transceiver may include a plurality of forward channel receivers. At least one of the forward channel receivers may receive (1) a forward channel laser communication beam transmitted from a ground station and (2) an E-band frequency having a bandwidth of 81-86 GHz. The transceiver may also include a plurality of forward channel transmitters having different frequencies. The forward channel transmitters may transmit user beams to endpoint devices, wherein the user beams are derived from the forward channel laser and MMW communication beams. The transceiver may also include a plurality of return channel receivers, wherein the return channel receivers receive user beams from the endpoint devices. The transceiver may also include at least one return channel transmitter, wherein the return channel transmitter transmits a return channel laser communication beam to a ground station.
    Type: Application
    Filed: December 28, 2017
    Publication date: July 5, 2018
    Inventors: Hamid Hemmati, Abhishek Tiwari
  • Publication number: 20170054527
    Abstract: Systems and methods for optical communication through air or space are disclosed. A method includes encoding one or more data frames with a data-link layer forward error correction (FEC) code to produce a plurality of encoded data frames and transmitting the plurality of encoded data frames from a transmitter (TX) to a receiver (RX) at least partially through air or space using a plurality of optical beams. The RX identifies a corrupted encoded data frame and reconstructs the corrupted encoded data frame using a data-link layer FEC decoder operating over a plurality of non-corrupted encoded data frames.
    Type: Application
    Filed: August 17, 2015
    Publication date: February 23, 2017
    Inventors: Kevin Michael Birnbaum, Kevin Jerome Quirk, Hamid Hemmati, Chien-Chung Chen, Gary Mak
  • Publication number: 20070229993
    Abstract: An optical system and associated method are provided. Included is at least one telescope. Further provided is a deformable mirror operable to compensate for optical aberrations resulting from the telescope.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 4, 2007
    Inventors: Hamid Hemmati, Yijiang Chen
  • Patent number: 6347101
    Abstract: A solid state laser includes a high absorption coefficient solid state gain medium such as Nd:YVO4 that is side pumped with a semiconductor laser diode array. The resonant cavity of the solid state laser is positioned so that the TEM00 mode is spaced from the face of the laser through which the laser is pumped by a distance sufficient to reduce diffraction losses but sufficiently near to allow coupling of pump light into the gain mode. The gain medium, the doping level of the gain medium, and the operating temperature of the pump laser are selected to efficiently couple pump light into the gain mode. The pump laser is positioned to side pump the gain medium without collimating or focusing optics between the pump laser and the face of the gain medium. A gap between the pump laser and the gain medium is empirically selected to match the angular extent of the pump laser output light to the height of the gain mode at the position of the gain mode fixed to optimize coupling and diffraction losses.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: February 12, 2002
    Assignee: 3D Systems, Inc.
    Inventors: Xingkun Wu, Jouni P. Partanen, William F. Hug, Hamid Hemmati
  • Patent number: 6157663
    Abstract: A solid-state laser includes a high-absorption coefficient solid-state gain medium such as Nd:YVO.sub.4 that is side pumped with a semiconductor laser diode array. The resonant cavity of the solid-state laser is positioned so that the TEM.sub.00 mode is spaced from the face of the laser through which the laser is pumped by a distance sufficient to reduce diffraction losses but sufficiently near to allow coupling of pump light into the gain mode. The gain medium, the doping level of the gain medium, and the operating temperature of the pump laser are selected to efficiently couple pump light into the gain mode. The pump laser is positioned to side pump the gain medium without collimating or focusing optics between the pump laser and the face of the gain medium. A gap between the pump laser and the gain medium is empirically selected to match the angular extent of the pump laser output light to the height of the gain mode at the position of the gain mode fixed to optimize coupling and diffraction losses.
    Type: Grant
    Filed: April 16, 1998
    Date of Patent: December 5, 2000
    Assignee: 3D Systems, Inc.
    Inventors: Xingkun Wu, Jouni P. Partanen, William F. Hug, Hamid Hemmati
  • Patent number: 5982788
    Abstract: The fabrication of an optical cavity for use in a laser, in a frequency doubling external cavity, or any other type of nonlinear optical device, can be simplified by providing the nonlinear crystal in combination with a surrounding glass having an index of refraction substantially equal to that of the nonlinear crystal. The closed optical path in this cavity is formed in the surrounding glass and through the nonlinear crystal which lies in one of the optical segments of the light path. The light is transmitted through interfaces between the surrounding glass in the nonlinear crystal through interfaces which are formed at the Brewster-angle to minimize or eliminate reflection.
    Type: Grant
    Filed: November 5, 1997
    Date of Patent: November 9, 1999
    Assignee: California Institute of Technology
    Inventor: Hamid Hemmati
  • Patent number: 5408480
    Abstract: An optically driven interactive Q-switch, i.e., a Q-switch that responds to a short pulse of light, for example, from external light-emitting diodes (LEDs) or diode lasers, is provided for producing an output laser pulse from electronic energy stored in a laser medium. Q-switching is thus achieved on demand by electrically pulsing the light source to produce a pulse of light directed onto a Q-switch medium in the laser cavity. Electronic control of the light pulse from the external source will thus provide not only efficient Q-switching frequency but also independent control of output laser pulse width with a fast rise time for each output laser pulse.
    Type: Grant
    Filed: July 15, 1993
    Date of Patent: April 18, 1995
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Hamid Hemmati
  • Patent number: 5347392
    Abstract: An electro-optic resonant cavity is used to achieve phase modulation with lower driving voltages. Laser damage thresholds are inherently higher than with previously used integrated optics due to the utilization of bulk optics. Phase modulation is achieved at higher speeds with lower driving voltages than previously obtained with non-resonant electro-optic phase modulators. The instant scheme uses a data locking dither approach as opposed to the conventional sinusoidal locking schemes. In accordance with a disclosed embodiment, a resonant cavity modulator has been designed to operate at a data rate in excess of 100 Mbps. By carefully choosing the cavity finesse and its dimension, it is possible to control the pulse switching time to within 4 ns and to limit the required switching voltage to within 10 V. Experimentally, the resonant cavity can be maintained on resonance with respect to the input laser signal by monitoring the fluctuation of output intensity as the cavity is switched.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: September 13, 1994
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Chien-Chung Chen, Deborah L. Robinson, Hamid Hemmati
  • Patent number: 4974230
    Abstract: A Ho:YLF crystal including Tm as sensitizers for the activator Ho, is optically pumped with a semiconductor diode laser array to generate 2.1 .mu.m radiation with a pump power to output power of efficiency as high as 68%. The prior-art dual sensitizer system of Er and Tm requires cooling, such as by LN.sub.2, but by using Tm alone and decreasing the concentrations of Tm and Ho, and decreasing the length of the laser rod to about 1 cm, it has been demonstrated that laser operation can be obtained from a temperature of 77.degree. K. with an efficiency as high as 68% up to ambient room temperature with an efficiency at that temperature as high as 9%.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: November 27, 1990
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventor: Hamid Hemmati
  • Patent number: 4664057
    Abstract: A photoprocessing apparatus for processing substrates includes a chamber for holding the substrates and a light source for providing an electromagnetic beam along an axis. A substantially conical reflector is positioned along the axis of the electromagnetic beam to reflect the electromagnetic beam as a plane of light into the chamber. The substrates are arranged in the chamber with respect to the plane of light reflected by the substantially conical reflector, by being either substantially parallel to or substantially normal to the plane of light. If the substrates are substantially parallel to the plane of light and the chamber is filled with a reaction gas, photo-deposition will occur when the plane of light irradiates the reaction gas adjacent to a substrate, so that a film is deposited on the substrate. Other photoprocessing techniques such as photo-etching can be performed when the substrates are arranged normal to the plane of light.
    Type: Grant
    Filed: December 20, 1985
    Date of Patent: May 12, 1987
    Assignee: Allied Corporation
    Inventor: Hamid Hemmati