Patents by Inventor Sang Gug Lee

Sang Gug Lee 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: 11665032
    Abstract: A method and apparatus for modulating/demodulating an FSK signal capable of overcoming a trade-off relationship between a modulation index and a spectral efficiency are disclosed. An apparatus for modulating/demodulating a frequency deviation keying (FSK) signal includes a channel selection-modulator, a phase locked loop, and an output unit. The channel selection-modulator modulates an FSK signal by setting a frequency channel to be used. The phase locked loop generates a desired output frequency ‘fout’ compared to a reference frequency ‘fREF’ by adjusting a frequency division ratio (N+n) with respect to a frequency of the modulated FSK signal. The output unit amplifies the FSK signal having the generated output frequency ‘fout’ and radiating the amplified FSK signal through an antenna. Here, each of the frequency channels is divided into two or more tones, and different frequency channels are allocated between the tones divided into two or more tones.
    Type: Grant
    Filed: September 25, 2019
    Date of Patent: May 30, 2023
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Eui-Rim Jeong, Jinho Ko, Keun-Mok Kim
  • Publication number: 20230029579
    Abstract: A power management integrated circuit includes a reconfigurable converter connected to a rechargeable battery and a control circuit. The reconfigurable converter includes an indcutor to accumulate energy based on an input voltage from a thermoelectric device, provides a wireless sensor node connected to an output node with an output voltage based on the input voltage and an internal input voltage of the rechargeable battery, operates in one of operation modes based on an available power provided from the thermoelectric device and a power consumption by the wireless sensor node and drives the wireless sensor node in response to the wireless sensor node consuming a current greater than a maximum current generated by the thermoelectric device. The control circuit to control the reconfigurable converter based on the input voltage, a first voltage of a first switching node, a second voltage of a second switching node and the output voltage.
    Type: Application
    Filed: April 26, 2022
    Publication date: February 2, 2023
    Applicant: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Sang-Gug Lee, Young-Seok Noh, Jeong-Il Seo, Won-Jong Choi
  • Publication number: 20220393651
    Abstract: Provided is a high-gain amplifier based on double-gain boosting including a first gain amplification unit including a first amplifier, a second amplifier, and a an interstage matching network connected between the first amplifier and the second amplifier and performing primary amplification; and a second gain amplification unit connected in parallel with the first gain amplification unit and performing secondary boosting.
    Type: Application
    Filed: June 2, 2021
    Publication date: December 8, 2022
    Inventors: Sang Gug Lee, Dae Woong Park, Dzuhri Radityo Utomo, Byeong Hun Yun
  • Publication number: 20220239535
    Abstract: A method and apparatus for modulating/demodulating an FSK signal capable of overcoming a trade-off relationship between a modulation index and a spectral efficiency are disclosed. An apparatus for modulating/demodulating a frequency deviation keying (FSK) signal includes a channel selection-modulator, a phase locked loop, and an output unit. The channel selection-modulator modulates an FSK signal by setting a frequency channel to be used. The phase locked loop generates a desired output frequency ‘fout’ compared to a reference frequency ‘fREF’ by adjusting a frequency division ratio (N+n) with respect to a frequency of the modulated FSK signal. The output unit amplifies the FSK signal having the generated output frequency ‘fout’ and radiating the amplified FSK signal through an antenna. Here, each of the frequency channels is divided into two or more tones, and different frequency channels are allocated between the tones divided into two or more tones.
    Type: Application
    Filed: September 25, 2019
    Publication date: July 28, 2022
    Applicant: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug LEE, Eui-Rim JEONG, Jinho KO, Keun-Mok KIM
  • Publication number: 20190372809
    Abstract: There is provided a wireless receiver. The wireless receiver includes an IQ modulator configured to generate an in-phase signal and a quadrature-phase signal from input signals modulated by a frequency modulation scheme and a modulation scheme converter configured to convert a modulation scheme of the in-phase signal and the quadrature-phase signal outputted from the IQ modulator into an amplitude modulation scheme. Further, the wireless receiver includes a bandpass filter configured to pass bandpass signals in which the modulation scheme is converted into the amplitude modulation scheme by the modulation scheme converter.
    Type: Application
    Filed: September 7, 2018
    Publication date: December 5, 2019
    Inventors: Sang Gug LEE, Hyun Gi SEOK, Oh Yong JUNG, Keun Mok KIM, Kyung Sik CHOI, Seok Kyun HAN
  • Patent number: 10199917
    Abstract: A current mode hysteretic buck converter employing an auto-selectable frequency locking circuit is disclosed. The auto-selectable frequency locking type buck converter include a current mode hysteretic buck converter for converting an input DC voltage into a lower DC voltage, and a frequency locking unit for locking a switching frequency of the current mode hysteretic buck converter wherein the switching frequency is locked through adjusting a locking value of the switching frequency to be a predetermined value according to a size of a load. The buck converter is, based on the current mode hysteretic control, related to a circuit that locks the switching frequency of the converter to reduce the difficulty of designing electromagnetic interference (EMI) filters in the converter. In addition, the buck converter can improve the efficiency at light load by adjusting the switching frequency which is locked according to the load current.
    Type: Grant
    Filed: August 30, 2017
    Date of Patent: February 5, 2019
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Jeong-Il Seo, Baek-Min Lim
  • Patent number: 10161804
    Abstract: An electromagnetic wave generator includes a 2DEG plate, a first resistor, a second resistor, a source and a floating plate and a dielectric body. The 2DEG plate is configured to form a 2DEG channel. The first resistor is connected to one side node of the 2DEG plate. The second resistor is connected to an opposite side node of the 2DEG plate. The source is disposed between the second resistor and a ground and configured to apply electric power to the 2DEG plate. The floating plate is configured to generate an electromagnetic wave using electric dipoles formed by the 2DEG channel. The dielectric body is formed between the 2DEG plate and the floating plate.
    Type: Grant
    Filed: December 30, 2014
    Date of Patent: December 25, 2018
    Assignee: UNIST (ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY)
    Inventors: Kyung Rok Kim, Jong Ryul Park, Sung Ho Kim, Sang Gug Lee
  • Patent number: 9985466
    Abstract: Disclosed is an optimized battery charging method based on thermodynamic information of a battery. Thermodynamic information on a material structure of a battery, for instance, entropy of the battery is extracted. Boundary points at which state transitions of the battery material are determined using the thermodynamic information extracted. Phases of the battery are identified based on the boundary points determined. The most appropriate charging patterns adapted to each of the phases identified are determined. A charging algorithm for charging the battery can be constructed by combining the most appropriate charging patterns determined. This charging algorithm is applied to the charging of the battery.
    Type: Grant
    Filed: February 16, 2016
    Date of Patent: May 29, 2018
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Guillaume Thenaisie
  • Publication number: 20180123440
    Abstract: A current mode hysteretic buck converter employing an auto-selectable frequency locking circuit is disclosed. The auto-selectable frequency locking type buck converter include a current mode hysteretic buck converter for converting an input DC voltage into a lower DC voltage, and a frequency locking unit for locking a switching frequency of the current mode hysteretic buck converter wherein the switching frequency is locked through adjusting a locking value of the switching frequency to be a predetermined value according to a size of a load. The buck converter is, based on the current mode hysteretic control, related to a circuit that locks the switching frequency of the converter to reduce the difficulty of designing electromagnetic interference (EMI) filters in the converter. In addition, the buck converter can improve the efficiency at light load by adjusting the switching frequency which is locked according to the load current.
    Type: Application
    Filed: August 30, 2017
    Publication date: May 3, 2018
    Applicant: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Jeong-Il Seo, Baek-Min Lim
  • Patent number: 9923453
    Abstract: A power management device according to example embodiments includes a self-startup circuit including an oscillator and a voltage multiplier to generate a start-up voltage in a first start-up period based on an input voltage, a boost converter to alternately charge the start-up voltage and an output voltage within a start-up voltage range during a second start-up period and to charge only the output voltage during an operation period, a controller to control the self-startup circuit and the boost converter based on a magnitude of the start-up voltage, a voltage charger including a start-up voltage capacitor and an output voltage capacitor, and a shared inductor connected between the input node and a common input node. The shared inductor operates as a part of the oscillator during the first start-up period and a part of the boost converter during the second start-up and operation periods.
    Type: Grant
    Filed: May 24, 2017
    Date of Patent: March 20, 2018
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Baek-Min Lim, Jeong-Il Seo, Young-Seok Noh, Hyun-Mo Gu
  • Patent number: 9748932
    Abstract: A phase locked loop includes a signal receiver configured to generate a mixed signal based on the received signal and an oscillator signal, and a frequency control circuit configured to compare the mixed signal to a reference signal, and adjust the oscillator signal based on a result of the comparing.
    Type: Grant
    Filed: August 24, 2015
    Date of Patent: August 29, 2017
    Assignees: Samsung Electronics Co., Ltd., Korea Advanced Institute of Science and Technology
    Inventors: Jaesup Lee, Sang-Gug Lee, Jae-Seung Lee, Seok-Kyun Han
  • Publication number: 20170229891
    Abstract: Disclosed is an optimized battery charging method based on thermodynamic information of a battery. Thermodynamic information on a material structure of a battery, for instance, entropy of the battery is extracted. Boundary points at which state transitions of the battery material are determined using the thermodynamic information extracted. Phases of the battery are identified based on the boundary points determined. The most appropriate charging patterns adapted to each of the phases identified are determined. A charging algorithm for charging the battery can be constructed by combining the most appropriate charging patterns determined. This charging algorithm is applied to the charging of the battery.
    Type: Application
    Filed: February 16, 2016
    Publication date: August 10, 2017
    Inventors: Sang-Gug LEE, Guillaume THENAISIE
  • Publication number: 20170146608
    Abstract: Disclosed is a method of dynamically extracting entropy of battery. At every measurement of a SOC of a battery estimated in a BMS, a temperature of the battery is measured and an OCV of the battery is estimated and then stored. Entropy of the current state of the battery can be obtained through calculation using the temperature value and the OCV value newly stored. SOH and SOC of the battery are updated based on the entropy value newly calculated. The conventional BMS estimates SOH through internal resistance of the battery without using the entropy, but the method allows thermodynamically and analytically understanding the internal state of the battery by using the entropy, and conceiving precisely the battery state by monitoring SOH as well as SOS.
    Type: Application
    Filed: February 16, 2016
    Publication date: May 25, 2017
    Inventors: SANG-GUG LEE, Guillaume Thenaisie
  • Publication number: 20170133860
    Abstract: For wireless power transfer, an energy field is formed by a power transmitter in a space near a transmission coil to provide a transmission power in the space of the energy field. A transferred power is receiver by a power receiver through a reception coil in the space of the energy field. An amount of the transferred power is reduced by the power receiver by performing a regulating operation using a switching frequency when the transferred power is excessive. The power transmitter detects a switching frequency signal having the switching frequency that is induced in the transmission coil when the power receiver performs the regulating operation. The power transmitter controls adjustment of the transmission power in response to the detection of the switching frequency signal. The transmission power is adjusted without a data communication for adjustment of the transmission power between the power transmitter and the power receiver.
    Type: Application
    Filed: February 3, 2016
    Publication date: May 11, 2017
    Inventors: Sang-Gug Lee, Ngan Hoang, Guillaume Thenaisie, Jeong-Seon Lee
  • Patent number: 9625322
    Abstract: Provided is an antenna module that comprises an antenna comprising a radiation patch for transmitting or receiving the terahertz wave, and a first ground disposed away from the radiation patch, the first ground having a hole, an integrated circuit board having a signal processing unit configured to generate the terahertz wave or to process the terahertz wave received through the antenna, the integrated circuit board being disposed under the antenna and a via configured to connect the radiation patch with the signal processing unit, the via passing through the hole.
    Type: Grant
    Filed: October 8, 2014
    Date of Patent: April 18, 2017
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Sun-A Kim, Kyoung-Young Choi, Dae-Woong Park, Seok-Kyun Han
  • Publication number: 20170052071
    Abstract: An electromagnetic wave generator includes a 2DEG plate, a first resistor, a second resistor, a source and a floating plate and a dielectric body. The 2DEG plate is configured to form a 2DEG channel. The first resistor is connected to one side node of the 2DEG plate. The second resistor is connected to an opposite side node of the 2DEG plate. The source is disposed between the second resistor and a ground and configured to apply electric power to the 2DEG plate. The floating plate is configured to generate an electromagnetic wave using electric dipoles formed by the 2DEG channel. The dielectric body is formed between the 2DEG plate and the floating plate.
    Type: Application
    Filed: December 30, 2014
    Publication date: February 23, 2017
    Inventors: Kyung Rok Kim, Jong Ryul Park, Sung Ho Kim, Sang Gug Lee
  • Patent number: 9461600
    Abstract: The present invention provides a power gain-boosting technique for an amplifier in order to compensate for the decrease of Gmag in a transistor at high frequencies. A power gain-boosting technique of the present invention comprises the steps of: finding the Maximum Unilateral Gain or Mason's Invariant U of a transistor; designing a linear, lossless, reciprocal network embedding the transistor so that the final equivalent S-, Y-, or Z-parameters satisfy the condition: S ? 21 S 12 = Y 2 ? ? 1 Y 1 ? ? 2 = Z 2 ? ? 1 Z 1 ? ? 2 = - [ ( 2 ? U - 1 ) + 2 ? U ? ( U - 1 ) ] ; embedding the transistor into the linear, lossless, reciprocal network; and constructing simultaneous conjugate matching.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: October 4, 2016
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Bao Lam Huu, Suna Kim, Jeong Seon Lee
  • Publication number: 20160248429
    Abstract: A phase locked loop includes a signal receiver configured to generate a mixed signal based on the received signal and an oscillator signal, and a frequency control circuit configured to compare the mixed signal to a reference signal, and adjust the oscillator signal based on a result of the comparing.
    Type: Application
    Filed: August 24, 2015
    Publication date: August 25, 2016
    Applicants: KOREA ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Jaesup Lee, Sang-Gug Lee, Jae-Seung Lee, Seok-Kyun Han
  • Publication number: 20160209268
    Abstract: Provided is a terahertz receiver for high data rate including: a detector including a field effect transistor (FET) configured to convert a terahertz wave signal received by a receiving antenna to an electric current; and a measuring device configured to read out an electric current output from the detector.
    Type: Application
    Filed: February 5, 2015
    Publication date: July 21, 2016
    Inventors: Sang-Gug LEE, Sun-A KIM, Dae-Woong PARK, Seok-Kyun HAN
  • Patent number: 9341709
    Abstract: Provided is an image sensing device that includes a detector configured to detect a terahertz wave signal received by a receiving antenna, a voltage-controlled oscillator configured to output an oscillation frequency according to an output voltage of the detector, and a frequency digital converter configured to convert the oscillation frequency output from the voltage-controlled oscillator to a digital signal.
    Type: Grant
    Filed: September 18, 2014
    Date of Patent: May 17, 2016
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Sang-Gug Lee, Sun-A Kim, Kyoung-Young Choi, Dae-Woong Park, Seok-Kyun Han