Patents by Inventor Dongsoo Koh

Dongsoo Koh 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: 9118367
    Abstract: Embodiments provide transmitter topologies that improve the power efficiency and bandwidth of RF transmitters for high transmission power applications. In an embodiment, the common-emitter/source PA of conventional topologies is replaced with a current-input common-base/gate PA, which is stacked on top on an open-collector/drain current-output transmitter. The common-base/gate PA protects the output of the transmitter from large output voltage swings. The low input impedance of the common-base/gate PA makes the PA less susceptible to frequency roll-off, even in the presence of large parasitic capacitance produced by the transmitter. At the same time, the low input impedance of the common-base/gate PA reduces the voltage swing at the transmitter output and prevents the transmitter output from being compressed or modulated. In an embodiment, the DC output current of the transmitter is reused to bias the PA, which results in power savings compared to conventional transmitter topologies.
    Type: Grant
    Filed: March 22, 2013
    Date of Patent: August 25, 2015
    Assignee: Broadcom Corporation
    Inventors: Ray (Ramon) Gomez, Leonard Dauphinee, Massimo Brandolini, Jianhong Xiao, Dongsoo Koh, Young Shin, Chonghua Zhong, Reza Rahman Khan
  • Publication number: 20130235953
    Abstract: Embodiments provide transmitter topologies that improve the power efficiency and bandwidth of RF transmitters for high transmission power applications. In an embodiment, the common-emitter/source PA of conventional topologies is replaced with a current-input common-base/gate PA, which is stacked on top on an open-collector/drain current-output transmitter. The common-base/gate PA protects the output of the transmitter from large output voltage swings. The low input impedance of the common-base/gate PA makes the PA less susceptible to frequency roll-off, even in the presence of large parasitic capacitance produced by the transmitter. At the same time, the low input impedance of the common-base/gate PA reduces the voltage swing at the transmitter output and prevents the transmitter output from being compressed or modulated, In an embodiment, the DC output current of the transmitter is reused to bias the PA, which results in power savings compared to conventional transmitter topologies.
    Type: Application
    Filed: March 22, 2013
    Publication date: September 12, 2013
    Applicant: Broadcom Corporation
    Inventors: Ray (Ramon) GOMEZ, Leonard Dauphinee, Massimo Brandolini, Jianhong Xiao, Dongsoo Koh, Young Shin, Chonghua Zhong, Reza Rahman Khan
  • Patent number: 8417200
    Abstract: Embodiments provide transmitter topologies that improve the power efficiency and bandwidth of RF transmitters for high transmission power applications. In an embodiment, the common-emitter/source PA of conventional topologies is replaced with a current-input common-base/gate PA, which is stacked on top on an open-collector/drain current-output transmitter. The common-base/gate PA protects the output of the transmitter from large output voltage swings. The low input impedance of the common-base/gate PA makes the PA less susceptible to frequency roll-off, even in the presence of large parasitic capacitance produced by the transmitter. At the same time, the low input impedance of the common-base/gate PA reduces the voltage swing at the transmitter output and prevents the transmitter output from being compressed or modulated. In an embodiment, the DC output current of the transmitter is reused to bias the PA, which results in power savings compared to conventional transmitter topologies.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 9, 2013
    Assignee: Broadcom Corporation
    Inventors: Ray (Ramon) Gomez, Leonard Dauphinee, Massimo Brandolini, Jianhong Xiao, Dongsoo Koh, Young Shin, Chonghua Zhong, Rezaur Rahman Khan
  • Publication number: 20130084816
    Abstract: Embodiments provide transmitter topologies that improve the power efficiency and bandwidth of RF transmitters for high transmission power applications. In an embodiment, the common-emitter/source PA of conventional topologies is replaced with a current-input common-base/gate PA, which is stacked on top on an open-collector/drain current-output transmitter. The common-base/gate PA protects the output of the transmitter from large output voltage swings. The low input impedance of the common-base/gate PA makes the PA less susceptible to frequency roll-off, even in the presence of large parasitic capacitance produced by the transmitter. At the same time, the low input impedance of the common-base/gate PA reduces the voltage swing at the transmitter output and prevents the transmitter output from being compressed or modulated. In an embodiment, the DC output current of the transmitter is reused to bias the PA, which results in power savings compared to conventional transmitter topologies.
    Type: Application
    Filed: September 30, 2011
    Publication date: April 4, 2013
    Applicant: Broadcom Corporation
    Inventors: Ray (Ramon) Gomez, Leonard Dauphinee, Massimo Brandolini, Jianhong Xiao, Dongsoo Koh, Young Shin, Chonghua Zhong, Rezaur Rahman Khan
  • Patent number: 7542741
    Abstract: A system for compensating gain control variations in a power amplifier comprises a power control element configured to receive a power control signal and an instantaneous envelope power reference signal, an adder configured to combine the power control signal and the instantaneous envelope power reference signal to obtain a modified power level signal, and a mapping function configured to receive the modified power level signal and configured to alter a control input to a variable gain amplifier, the variable gain amplifier controlling an adjustable input to the power amplifier.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: June 2, 2009
    Assignee: Skyworks Solutions, Inc.
    Inventors: Dmitriy Rozenblit, Tirdad Sowlati, Dongsoo Koh
  • Publication number: 20070207749
    Abstract: A system for compensating gain control variations in a power amplifier comprises a power control element configured to receive a power control signal and an instantaneous envelope power reference signal, an adder configured to combine the power control signal and the instantaneous envelope power reference signal to obtain a modified power level signal, and a mapping function configured to receive the modified power level signal and configured to alter a control input to a variable gain amplifier, the variable gain amplifier controlling an adjustable input to the power amplifier.
    Type: Application
    Filed: January 31, 2006
    Publication date: September 6, 2007
    Inventors: Dmitriy Rozenblit, Tirdad Sowlati, Dongsoo Koh
  • Patent number: 6927637
    Abstract: An exemplary tuning circuit is coupled to, a voltage controlled oscillator. The tuning circuit comprises a lock detect monitoring circuit, a VTUNE monitoring circuit and an autotuner circuit. The lock detect monitoring circuit is coupled to a phase locked loop of the voltage controlled oscillator and is configured to determine a state of the phase locked loop. The VTUNE monitoring circuit is coupled to a loop filter of the voltage controlled oscillator and is configured to determine the fine tuning voltage generated by the loop filter. The autotuner circuit is connected to the lock detect monitoring circuit and the VTUNE monitoring circuit and is configured to provide coarse tuning of the voltage controlled oscillator based on the fine tuning voltage and the state of the phase locked loop.
    Type: Grant
    Filed: June 21, 2003
    Date of Patent: August 9, 2005
    Assignee: Skyworks Solutions, Inc.
    Inventors: Dongsoo Koh, Peter Good