Patents by Inventor Wang Rae Kim

Wang Rae Kim 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: 11384189
    Abstract: The present invention provides a graft copolymer comprising (A) a seed comprising units derived from an alkyl methacrylate monomer; (B) a core formed on the seed and comprising units derived from an alkyl acrylate monomer; and (C) a shell formed on the core and comprising units derived from one or more one or more selected from the group consisting of an aromatic vinyl-based monomer, a vinyl cyanide-based monomer and an alkyl methacrylate monomer, wherein an average particle diameter of the core is 40 to 90 nm, and a graft ratio of the shell is 10 to 30%, and a thermoplastic resin composition and a thermoplastic resin molded article including the same.
    Type: Grant
    Filed: September 12, 2018
    Date of Patent: July 12, 2022
    Assignee: LG CHEM, LTD.
    Inventors: Min Jung Kim, Bong Keun Ahn, Yong Yeon Hwang, Wang Rae Joe, Jang Won Park
  • Patent number: 11377515
    Abstract: A method for preparing a graft copolymer includes the steps of: 1) preparing a seed by adding one or more selected from the group consisting of an alkyl (meth)acrylate-based monomer, an aromatic vinyl-based monomer, and a vinyl cyan-based monomer and carrying out polymerization; 2) preparing a core in the presence of the seed by adding an alkyl (meth)acrylate-based monomer and carrying out polymerization; and 3) preparing a shell in the presence of the core by adding an aromatic vinyl-based monomer and a vinyl cyan-based monomer and carrying out polymerization, wherein an activator including a compound represented by Chemical Formula 1 is added in the step 3). In Chemical Formula 1, R1 and R2 are each independently hydrogen, a C1-C10 alkyl group, or *-(C=O)OM2, provided that R1 and R2 are not both hydrogen, and M1 and M2 are each independently an alkali metal.
    Type: Grant
    Filed: August 28, 2019
    Date of Patent: July 5, 2022
    Assignee: LG CHEM, LTD.
    Inventors: Bong Keun Ahn, Min Jung Kim, Wang Rae Joe, Yong Yeon Hwang, Jang Won Park, Ji Yoon Jeon
  • Patent number: 7340005
    Abstract: A signal transmission apparatus comprises a plurality of look-up tables (LUTs) corresponding to operation areas of a nonlinear transmission device, an operational characteristic calculator, a LUT selector, and a predistorter. The LUTs are adapted to store gain values of input signal magnitudes. The LUT selector selects a LUT corresponding to a calculated operational characteristic. The selected LUT generates a gain value output signal. The predistorter generates a predistorted signal from the gain value output signal and an input signal. The predistorted signal is input to a nonlinear transmission device.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: March 4, 2008
    Assignee: LG Electronics Inc.
    Inventors: Wang-Rae Kim, Kwang-Eun Ahn, Woo-Sik Kim
  • Patent number: 7034612
    Abstract: An apparatus and method that compensates for pre-distortion of a power amplifier includes a digital pre-distorter controller which generates a power/phase compensation coefficient, a temperature compensation coefficient and a frequency compensation coefficient, a look-up table which stores the coefficients, a pre-distorter kernel which pre-compensates an input signal based on the temperature compensation coefficient from the look-up table, and a correction filter which compensates an output signal of the kernel based on the frequency compensation coefficient from the look-up table. If desired, an input signal may be pre-distorted based on only one of the temperature and frequency compensation coefficients along with the power/phase compensation coefficient. Nonlinear characteristics of the power amplifier are accurately checked and distortion due to the nonlinear characteristics are compensated for.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: April 25, 2006
    Assignee: LG Electronics Inc.
    Inventor: Wang-Rae Kim
  • Patent number: 6853691
    Abstract: A vector modulator is disclosed which includes a first amplitude invariant phase shifter for shifting a phase of a received signal at fixed intervals within a preset first shifting range and a quadrature hybrid coupler for separating an output of the first amplitude invariant phase shifter into at least two different channel signals having a 90° phase difference to each other. A second amplitude invariant phase shifter shifts a phase of a first channel signal among outputs of the quadrature hybrid coupler by a fixed amplitude within a prescribed second shifting range and a third amplitude invariant phase shifter shifts a phase of a second channel signal among outputs of the quadrature hybrid coupler by a fixed amplitude within a prescribed third shifting range.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: February 8, 2005
    Assignee: LG Information & Communications, Ltd.
    Inventor: Wang Rae Kim
  • Publication number: 20040252783
    Abstract: A signal transmission apparatus comprises a plurality of look-up tables (LUTs) corresponding to operation areas of a nonlinear transmission device, an operational characteristic calculator, a LUT selector, and a predistorter. The LUTs are adapted to store gain values of input signal magnitudes. The LUT selector selects a LUT corresponding to a calculated operational characteristic. The selected LUT generates a gain value output signal. The predistorter generates a predistorted signal from the gain value output signal and an input signal. The predistorted signal is input to a nonlinear transmission device.
    Type: Application
    Filed: June 3, 2004
    Publication date: December 16, 2004
    Applicant: LG Electronics Inc.
    Inventors: Wang-Rae Kim, Kwang-Eun Ahn, Woo-Sik Kim
  • Publication number: 20040017257
    Abstract: An apparatus and method that compensates for pre-distortion of a power amplifier includes a digital pre-distorter controller which generates a power/phase compensation coefficient, a temperature compensation coefficient and a frequency compensation coefficient, a look-up table which stores the coefficients, a pre-distorter kernel which pre-compensates an input signal based on the temperature compensation coefficient from the look-up table, and a correction filter which compensates an output signal of the kernel based on the frequency compensation coefficient from the look-up table. If desired, an input signal may be pre-distorted based on only one of the temperature and frequency compensation coefficients along with the power/phase compensation coefficient. Nonlinear characteristics of the power amplifier are accurately checked and distortion due to the nonlinear characteristics are compensated for.
    Type: Application
    Filed: July 18, 2003
    Publication date: January 29, 2004
    Applicant: LG ELECTRONICS INC.
    Inventor: Wang-Rae Kim
  • Patent number: 6600368
    Abstract: A predistortion linearizer of a power amplifier capable of improving the nonlinearity of the power amplifier by compensating changes in the power amplifier's nonlinear characteristics according to the lapse of time or an external environment and easily implementing the reverse characteristics of the power amplifier's nonlinear characteristics is disclosed. The predistortion linearizer of the power amplifier as disclosed includes a control unit for controlling a gain and phase of an input signal so that they are the reverse of the power amplifier's nonlinear characteristics, and a unit for compensating changes in the power amplifier's distortion characteristics according to the lapse of time or an external environment, upon receipt of the output of the control unit.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: July 29, 2003
    Assignee: LG Electronics Inc.
    Inventor: Wang Rae Kim
  • Publication number: 20020181611
    Abstract: An AQM error compensating apparatus includes: a predistorter for distorting a signal so as to have the opposite characteristics of nonlinear distortion characteristics of a digital input signal; an error compensating unit for compensating I/Q digital signals outputted from the predistorter according to an error correction signal; a digital/analog converter for converting the I/Q digital signals of the error compensating unit into I/Q analog signals; a modulator for frequency-modulating the I/Q analog signals outputted from the digital/analog converter; a power amplifier for amplifying the output signal of the modulator to a directional coupler; a down-converter for down-converting a feedback signal inputted from the directional coupler; an analog/digital converter for converting the output signal of the down-converter into a digital signal; and a controller for comparing the output signal of the analog/digital converter with the I/Q digital signals inputted from the predistorter, and applying an extracted err
    Type: Application
    Filed: May 31, 2002
    Publication date: December 5, 2002
    Applicant: LG Electronics Inc.
    Inventor: Wang Rae Kim
  • Publication number: 20020034260
    Abstract: An adaptive predistortion transmitter is disclosed. The transmitter includes a predistortion unit that distorts a digital input signal to have a non-linear characteristic opposite to that of the whole transmitter. A radio frequency converter converts an output signal of the predistortion unit into a radio frequency signal and an HPA amplifies the radio frequency converter. An error detector detects a non-linear characteristic change of the whole transmitter, by comparing the digital input signal and the output signal of the HPA, and controls an operation of the predistortion unit. The predistortion unit is implemented in consideration of the non-linear characteristic of the whole transmitter, including the up-converter and the HPA. Thus, the non-linear characteristic of the transmitter can be effectively improved. In addition, since the predistortion unit and a direct IF up-converter are implemented in one chip, the design structure of the whole transmitter can be simplified.
    Type: Application
    Filed: September 14, 2001
    Publication date: March 21, 2002
    Applicant: LG Electronics Inc.
    Inventor: Wang Rae Kim
  • Publication number: 20010004223
    Abstract: A predistortion linearizer of a power amplifier capable of improving the nonlinearity of the power amplifier by compensating changes in the power amplifier's nonlinear characteristics according to the lapse of time or an external environment and easily implementing the reverse characteristics of the power amplifier's nonlinear characteristics is disclosed. The predistortion linearizer of the power amplifier as disclosed includes a control unit for controlling a gain and phase of an input signal so that they are the reverse of the power amplifier's nonlinear characteristics, and a unit for compensating changes in the power amplifier's distortion characteristics according to the lapse of time or an external environment, upon receipt of the output of the control unit.
    Type: Application
    Filed: December 20, 2000
    Publication date: June 21, 2001
    Applicant: LG Electronics, Inc.
    Inventor: Wang Rae Kim
  • Patent number: 6169451
    Abstract: A system for sensing the operating state of a tower top amplifier for mobile communication system, includes a plurality of tower top amplifiers each connected to communication antennas; and an operating state management part monitoring the operating state of each tower top amplifier. The operating state management part monitors the operating state of each tower top amplifier by the use of a single power supply line connected between itself and each tower top amplifier. In a method of sensing the operating state of a tower top amplifier for mobile communication system, the operating state of each tower top amplifier is monitored by using an amount of consumed DC power applied to the respective tower top amplifiers. This method includes the steps of measuring a potential difference of a given section of the DC power applied to each tower top amplifier; and comparing a result obtained by the measuring step and determining the normal or abnormal states of the tower top amplifiers.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: January 2, 2001
    Assignee: LG Information & Communications Ltd.
    Inventor: Wang Rae Kim