Patents by Inventor Dubravko Babic

Dubravko Babic 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: 20220393931
    Abstract: A modulated RF carrier produced at the output of the polar transmitter's switch-mode power amplifier (SMPA) is conveyed to an output filter network comprising a harmonic low-pass filter (LPF) connected in parallel with an absorptive high-pass filter (HPF). Together the harmonic LPF and absorptive HPF pass the fundamental component of the modulated RF carrier to the polar transmitter's load while also absorbing higher harmonic components that would otherwise be undesirably reflected back toward the output of the SMPA.
    Type: Application
    Filed: May 31, 2022
    Publication date: December 8, 2022
    Inventors: Fran Kostelac, Ante Brizic, Dubravko Babic
  • Patent number: 9692517
    Abstract: This application discloses apparatuses and methods for controlling a multi-longitudinal mode device seeded or wavelength locked to a spectrum-sliced external wavelength by either self-seeding or broadband light-source seeding through an array-waveguide grating.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: June 27, 2017
    Assignee: University of Zagreb, Faculty of Electrical Engineering and Computing
    Inventors: Marko Sprem, Dubravko Babic
  • Publication number: 20170180051
    Abstract: This application discloses apparatuses and methods for controlling a multi-longitudinal mode device seeded or wavelength locked to a spectrum-sliced external wavelength by either self-seeding or broadband light-source seeding through an array-waveguide grating.
    Type: Application
    Filed: March 6, 2017
    Publication date: June 22, 2017
    Applicant: University of Zagreb, Faculty of Electrical Engine ering and Computing
    Inventors: Marko Sprem, Dubravko Babic
  • Patent number: 9667026
    Abstract: A connected optical waveguide structure comprises n four-port optical couplers, where n is greater than one; and n waveguide loops, each loop having a corresponding perimeter; wherein each of the n perimeters is different from each of the other n?1 perimeters. In one embodiment, for any pair of the n loops, the ratio of the larger perimeter to the smaller perimeter is greater than five halves (5/2).
    Type: Grant
    Filed: September 1, 2015
    Date of Patent: May 30, 2017
    Assignee: University of Zagreb
    Inventors: Tin Komljenovic, Dubravko Babic, Zvonimir Sipus
  • Patent number: 9628175
    Abstract: This application discloses apparatuses and methods for selecting and tuning of a select mode of a multi-longitudinal mode device seeded or wavelength locked to a spectrum-sliced external wavelength by either self-seeding or broadband light-source seeding through an array-waveguide grating.
    Type: Grant
    Filed: July 25, 2015
    Date of Patent: April 18, 2017
    Inventors: Marko Sprem, Dubravko Babic
  • Patent number: 9614622
    Abstract: A fiber-optic transmitter comprises a transmitter optical port, an optical circulator, a semiconductor optical amplifier, and a two-port modulation-averaging structure. The optical circulator has at least three ports, a first one of the three circulator ports being optically coupled to the transmitter optical port. The semiconductor optical amplifier has an input optical port, an output optical port, and an electrical input port. The two-port modulation-averaging structure is optically coupled between the input optical port and a third one of the three circulator ports.
    Type: Grant
    Filed: September 22, 2015
    Date of Patent: April 4, 2017
    Inventors: Dubravko Babic, Tin Komljenovic, Zvonimir Sipus
  • Publication number: 20170063022
    Abstract: A connected optical waveguide structure comprises n four-port optical couplers, where n is greater than one; and n waveguide loops, each loop having a corresponding perimeter; wherein each of the n perimeters is different from each of the other n?1 perimeters. In one embodiment, for any pair of the n loops, the ratio of the larger perimeter to the smaller perimeter is greater than five halves (5/2).
    Type: Application
    Filed: September 1, 2015
    Publication date: March 2, 2017
    Applicant: University of Zagreb, Faculty of Electrical Engineering and Computing
    Inventors: Tin Komljenovic, Dubravko Babic, Zvonimir Sipus
  • Publication number: 20170026116
    Abstract: This application discloses apparatuses and methods for selecting and tuning of a select mode of a multi-longitudinal mode device seeded or wavelength locked to a spectrum-sliced external wavelength by either self-seeding or broadband light-source seeding through an array-waveguide grating.
    Type: Application
    Filed: July 25, 2015
    Publication date: January 26, 2017
    Applicant: University of Zagreb, Faculty of Electrical Engineering and Computing
    Inventors: Marko Sprem, Dubravko Babic
  • Patent number: 9490756
    Abstract: A phase-stiff radio frequency power amplifier (RFPA) is disclosed. The high phase-stiffness property of the RFPA obviates the need for a circulator or other isolation device in applications where the RFPA is used to implement the high-power amplifier in a transmit-receive module (TRM) configured for use in a phased array. The phase-stiff RFPA is designed to operate in switch-mode, resulting in high energy efficiency. Together, the high energy efficiency and high phase-stiffness attributes of the RFPA afford the ability to construct a phased array having a SWaP (Size, Weight and Power) performance that far surpasses that which can be possibly achieved in a phased array constructed from conventional TRMs.
    Type: Grant
    Filed: January 18, 2016
    Date of Patent: November 8, 2016
    Assignee: Eridan Communications, Inc.
    Inventor: Dubravko Babic
  • Publication number: 20160036531
    Abstract: A fiber-optic transmitter comprises a transmitter optical port, an optical circulator, a semiconductor optical amplifier, and a two-port modulation-averaging structure. The optical circulator has at least three ports, a first one of the three circulator ports being optically coupled to the transmitter optical port. The semiconductor optical amplifier has an input optical port, an output optical port, and an electrical input port. The two-port modulation-averaging structure is optically coupled between the input optical port and a third one of the three circulator ports.
    Type: Application
    Filed: September 22, 2015
    Publication date: February 4, 2016
    Inventors: Dubravko Babic, Tin Komljenovic, Zvonimir Sipus
  • Publication number: 20150279945
    Abstract: Methods for manufacturing semiconductor wafer structures are described which exhibit improved lifetime and reliability. The methods comprise transferring an active semiconductor layer structure from a native non-lattice-matched semiconductor growth substrate to a working substrate, wherein strain-matching layers, and optionally a portion of the active semiconductor layer structure, are removed. In certain embodiment, the process of attaching the active semiconductor layer structure to the working substrate includes annealing at an elevated temperature for a specified time.
    Type: Application
    Filed: October 25, 2013
    Publication date: October 1, 2015
    Inventors: Daniel Francis, Dubravko Babic, Firooz Nasser-Faili, Felix Ejeckham, Quentin Diduck, Joseph Smart, Kristopher Matthews, Frank Lowe
  • Patent number: 8945966
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: February 3, 2015
    Assignee: Element Six Technologies US Corporation
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic
  • Publication number: 20140141595
    Abstract: Methods for integrating wide-gap semiconductors, and specifically, gallium nitride epilayers with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure that comprises at least one layer made out of gallium nitride. Methods for manufacturing GaN-on-diamond wafers with low bow and high crystalline quality are disclosed along with preferred choices for manufacturing GaN-on-diamond wafers and chips tailored to specific applications.
    Type: Application
    Filed: January 24, 2014
    Publication date: May 22, 2014
    Applicant: ELEMENT SIX TECHNOLOGIES US CORPORATION
    Inventors: Dubravko Babic, Firooz Nasser-Faili, Daniel Francis, Quentin Diduck, Felix Ejeckam
  • Publication number: 20130183798
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Application
    Filed: September 10, 2012
    Publication date: July 18, 2013
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic
  • Patent number: 8283672
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Grant
    Filed: June 12, 2009
    Date of Patent: October 9, 2012
    Assignee: Group4 Labs, Inc.
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic
  • Patent number: 8283189
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: October 9, 2012
    Assignee: Group4 Labs, Inc.
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic
  • Patent number: 7943485
    Abstract: Method for producing composite wafers with thin high-quality semiconductor films atomically attached to synthetic diamond wafers is disclosed. Synthetic diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited on bulk semiconductor wafer which has been prepared to allow separation of the thin semiconductor film from the remaining bulk semiconductor wafer. The remaining semiconductor wafer is available for reuse. The synthetic diamond substrate serves as heat spreader and a mechanical substrate.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: May 17, 2011
    Assignee: Group4 Labs, LLC
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Firooz Faili, Dubravko Babic
  • Publication number: 20100105166
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Application
    Filed: September 29, 2009
    Publication date: April 29, 2010
    Applicant: Group4 Labs, LLC
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic
  • Publication number: 20100001293
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Application
    Filed: June 12, 2009
    Publication date: January 7, 2010
    Applicant: Group4 Labs, LLC
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic
  • Patent number: 7595507
    Abstract: Methods for integrating wide-gap semiconductors with synthetic diamond substrates are disclosed. Diamond substrates are created by depositing synthetic diamond onto a nucleating layer deposited or formed on a layered structure including at least one layer of gallium nitride, aluminum nitride, silicon carbide, or zinc oxide. The resulting structure is a low stress process compatible with wide-gap semiconductor films, and may be processed into optical or high-power electronic devices. The diamond substrates serve as heat sinks or mechanical substrates.
    Type: Grant
    Filed: April 12, 2006
    Date of Patent: September 29, 2009
    Assignee: Group4 Labs LLC
    Inventors: Daniel Francis, Felix Ejeckam, John Wasserbauer, Dubravko Babic