Patents by Inventor James F. Buckwalter

James F. Buckwalter 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: 11914263
    Abstract: A predistorter for an electro-optical converter includes a plurality of low noise RF amplifiers distributed along a transmission line that receive an RF input. Second order intermodulation injection (IM2) circuitry includes an inductively-degenerated frequency doubler to square and filter IM2 products of the RF input. A Mach-Zehnder Modulator (MZM) is used for electro-optical conversion. Feed forward circuitry injects IM2 to independently propagate RF intermodulation components with velocity matching to the MZM. At least one driver injects the RF input and RF intermodulation components into the MZM.
    Type: Grant
    Filed: March 10, 2020
    Date of Patent: February 27, 2024
    Assignee: The Regents of the University of California
    Inventors: James F. Buckwalter, Navid Hosseinzadeh, Aditya Jain, Roger Helkey
  • Publication number: 20230353105
    Abstract: A passive, tunable on-chip load modulation network for a high-efficiency power amplifier includes a ring transmission line. An output is connected to a first point on the ring transmission line. A first switched input is connected to a second point on the ring transmission line, the second point being located on the ring transmission line to provide a first impedance transformation. A second switched input is connected to a third point on the ring transmission line, the third point being located to provide a second impedance transformation that is unique from the first impedance transformation.
    Type: Application
    Filed: April 25, 2023
    Publication date: November 2, 2023
    Inventors: Cameron Hill, James F. Buckwalter
  • Patent number: 11756848
    Abstract: An electronic assembly has a backside capping layer, a host wafer having a back surface bonded to a top surface of the backside capping layer except for cavities in the wafer formed over areas of the backside capping layer, the cavities having side surfaces of the wafer. Chiplets have backsides bonded directly to at least portion of the areas of the top surface of the backside capping layer. A lateral dielectric material between side surfaces of the chiplets and side surfaces of the wafer, mechano-chemically bonds the side surfaces of the chiplets to the side surfaces of the wafer.
    Type: Grant
    Filed: January 17, 2023
    Date of Patent: September 12, 2023
    Assignee: PseudolithIC, Inc.
    Inventors: Florian Herrault, Isaac Rivera, Daniel S. Green, James F. Buckwalter
  • Patent number: 11652447
    Abstract: Methods and apparatus for implementing a power efficient amplifier device through the use of a main (primary) and auxiliary (secondary) power amplifier are described. The primary and secondary amplifiers operate as current sources providing current to the load. Capacitance coupling is used to couple the primary and secondary amplifier outputs. In some embodiments the combination of primary and secondary amplifiers achieve high average efficiency over the operating range of the device in which the primary and secondary amplifiers are used in combination as an amplifier device. The amplifier device is well suited for implementation using CMOS technology, e.g., N-MOSFETs, and can be implemented in an integrated circuit space efficient manner that is well suited for supporting RF transmissions in the GHz frequency range, e.g., 30 GHz frequency range. The primary amplifier in some embodiments is a CLASS-AB or B amplifier and the secondary amplifier is a CLASS-C amplifier.
    Type: Grant
    Filed: August 13, 2020
    Date of Patent: May 16, 2023
    Assignee: Mixcomm, Inc.
    Inventors: James F. Buckwalter, Kang Ning
  • Publication number: 20220345165
    Abstract: A method for carrier aggregation receives a signal with multiple non-contiguous carrier bands. Frequency converting of the signal to a compressed single intermediate frequency band with a pseudonoise code applied to a local oscillation of each of the multiple non-contiguous carrier bands while maintaining separation of the multiple non-contiguous carrier bands permits reduced complexity digital signal processing to detect spectral power density and demodulate waveforms across multiple channels A receiver includes a pseudorandom noise generator applying a pseudo noise code to the local oscillator generator to produce a unique set of spectral tones in the output signal that sample-specific channels over the multiple non-contiguous carrier bands.
    Type: Application
    Filed: September 3, 2020
    Publication date: October 27, 2022
    Inventors: James F. Buckwalter, Hussam Alshammary
  • Publication number: 20220239384
    Abstract: A method for switching interval modulation includes modulating an RF input data signal while generating and inserting additional pulses in transitions of the data signal. The additional pulses are structured to shift transition noise into higher order harmonics. Higher order harmonics are easily filtered. The generating is conducted in the digital domain. The additional pulses can be used to simplify the transmit chain through optical modulators and improve the signal integrity over long distances, can be applied at the output of a transmitter to filter power amplifier distortion, and can be appplied to non-linear RF over fiber for a distributed MIMO system.
    Type: Application
    Filed: May 14, 2020
    Publication date: July 28, 2022
    Inventors: Cameron Hill, James F. Buckwalter
  • Publication number: 20220187675
    Abstract: A predistorter for an electro-optical converter includes a plurality of low noise RF amplifiers distributed along a transmission line that receive an RF input. Second order intermodulation injection (IM2) circuitry includes an inductively-degenerated frequency doubler to square and filter IM2 products of the RF input. A Mach-Zehnder Modulator (MZM) is used for electro-optical conversion. Feed forward circuitry injects IM2 to independently propagate RF intermodulation components with velocity matching to the MZM. At least one driver injects the RF input and RF intermodulation components into the MZM.
    Type: Application
    Filed: March 10, 2020
    Publication date: June 16, 2022
    Inventors: James F. Buckwalter, Navid Hosseinzadeh, Aditya Jain, Roger Helkey
  • Publication number: 20210050818
    Abstract: Methods and apparatus for implementing a power efficient amplifier device through the use of a main (primary) and auxiliary (secondary) power amplifier are described. The primary and secondary amplifiers operate as current sources providing current to the load. Capacitance coupling is used to couple the primary and secondary amplifier outputs. In some embodiments the combination of primary and secondary amplifiers achieve high average efficiency over the operating range of the device in which the primary and secondary amplifiers are used in combination as an amplifier device. The amplifier device is well suited for implementation using CMOS technology, e.g., N-MOSFETs, and can be implemented in an integrated circuit space efficient manner that is well suited for supporting RF transmissions in the GHz frequency range, e.g., 30 GHz frequency range. The primary amplifier in some embodiments is a CLASS-AB or B amplifier and the secondary amplifier is a CLASS-C amplifier.
    Type: Application
    Filed: August 13, 2020
    Publication date: February 18, 2021
    Inventors: James F. Buckwalter, Kang Ning
  • Patent number: 10333477
    Abstract: A circuit topology including stacked power amplifiers (e.g., class D PA cells) in a ladder arranged in a house-of-cards topology such that the number of stacked-domains follows a decaying triangular series N, N?1, N?2, . . . , N?i from a fixed ladder to an ith ladder to provide a 1:(i+1) voltage conversion ratio, each stacked domain outputs its power via a flying domain power amplifier cell, and each ladder balances stacked domains of a prior ladder and combines power from all prior ladders.
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: June 25, 2019
    Assignee: The Regents of the University of California
    Inventors: Loai Galal Bahgat Salem, James F. Buckwalter, Patrick P. Mercier
  • Publication number: 20180097486
    Abstract: A circuit topology including stacked power amplifiers (e.g., class D PA cells) in a ladder arranged in a house-of-cards topology such that the number of stacked-domains follows a decaying triangular series N, N?1, N?2, . . . , N?i from a fixed ladder to an ith ladder to provide a 1:(i+1) voltage conversion ratio, each stacked domain outputs its power via a flying domain power amplifier cell, and each ladder balances stacked domains of a prior ladder and combines power from all prior ladders.
    Type: Application
    Filed: September 7, 2017
    Publication date: April 5, 2018
    Inventors: Loai Galal Bahgat Salem, James F. Buckwalter, Patrick P. Mercier
  • Patent number: 7961778
    Abstract: In the context of high-speed serial links, data-dependent jitter compensation techniques performed using phase pre-distortion. Broadly contemplated is an expansion of the notion of pre-emphasis beyond conventional amplitude compensation of ISI, whereby phase pre-emphasis for compensating data-dependent jitter (DDJ) is introduced. DDJ can be addressed by exploiting the relationship between the data sequence and the timing deviation. Phase pre-emphasis improves the signal integrity with little additional power consumption in the transmitter and with no cross-talk penalty.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: June 14, 2011
    Assignee: International Business Machines Corporation
    Inventors: James F. Buckwalter, Daniel J. Friedman, Mounir Meghelli
  • Publication number: 20080298530
    Abstract: In the context of high-speed serial links, data-dependent jitter compensation techniques performed using phase pre-distortion. Broadly contemplated is an expansion of the notion of pre-emphasis beyond conventional amplitude compensation of ISI, whereby phase pre-emphasis for compensating data-dependent jitter (DDJ) is introduced. DDJ can be addressed by exploiting the relationship between the data sequence and the timing deviation. Phase pre-emphasis improves the signal integrity with little additional power consumption in the transmitter and with no cross-talk penalty.
    Type: Application
    Filed: July 22, 2008
    Publication date: December 4, 2008
    Applicant: International Business Machines Corporation
    Inventors: James F. Buckwalter, Daniel J. Friedman, Mounir Meghelli