Patents by Inventor Jae Ick Choi

Jae Ick Choi 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: 20090201220
    Abstract: Provided are a high impedance surface structure using an AMC (artificial magnetic conductor) and an antenna and an electromagnetic device using the high impedance surface structure. The high impedance surface structure includes: a ground layer formed of a first conductor layer; a first dielectric layer formed on the ground layer; and an HIS (high impedance surface) layer formed of second conductor layers and a second dielectric layer on the first dielectric layer, wherein the second conductor layers are interdigitated with one another and vias connecting the second conductor layers to the ground layer are not formed.
    Type: Application
    Filed: December 4, 2006
    Publication date: August 13, 2009
    Inventors: Dong-Ho Kim, Jae-Ick Choi, Dong-Uk Sim, Jong-Hwa Kwon
  • Publication number: 20090153275
    Abstract: Provided is a tunable magnetic field amplifying device capable of easily adjusting resonance frequencies and tuning usable bands by using discrete elements to vary electric properties of elements that are used for amplifying a magnetic field of a specific microwave band. The tunable magnetic field amplifying device includes a Swiss roll formed by winding a metal sheet coated with a dielectric in a spiral cylinder shape once or several times; and a tunable capacitor connected between an inner sheet of and an outer sheet of the metal sheet for tuning a resonance frequency.
    Type: Application
    Filed: July 30, 2008
    Publication date: June 18, 2009
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Wangjoo Lee, Dong-Ho Kim, Jae-Ick Choi
  • Publication number: 20090135077
    Abstract: Provided is a multi-band internal antenna of a symmetry structure having stub, in which a size of the internal antenna can be reduced by stacking loop antennas, a broadband characteristic can be obtained in a high frequency band by connecting the stub to a top patch of the antenna, and a reduced SAR and an omni-directional radiation pattern can be obtained by configuring an antenna patch in a symmetry structure.
    Type: Application
    Filed: July 4, 2005
    Publication date: May 28, 2009
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Byung-Chan Kim, Jae-Ick Choi, Byung-Je Lee, Byung-Woon Jung, Han-Phil Rhyu, Byung-Gil Yu
  • Publication number: 20090027279
    Abstract: A method of reducing electromagnetic field using metamaterial and a portable or wearable terminal having a structure for reducing an electromagnetic field using a metamaterial are provided. The method includes deciding a body contacting part of the portable or wearable terminal; and disposing an electromagnetic field reducing unit formed of metamaterial between an antenna and the decided body contacting part, wherein the metamaterial including a conductor and a dielectric adjusts a permittivity.
    Type: Application
    Filed: September 18, 2008
    Publication date: January 29, 2009
    Inventors: Hyung-Do Choi, Dong-Ho Kim, Dong-Uk Sim, Jae-Ick Choi, Ae-Kyoung Lee
  • Publication number: 20080079638
    Abstract: A method of reducing electromagnetic field using metamaterial and a terminal having a structure for reducing an electromagnetic field using a metamaterial are provided. The method includes the steps of: deciding a body contacting part of a portable terminal or a wearable terminal; and disposing an electromagnetic field absorption member formed of metamaterial between an antenna and the decided body contacting part.
    Type: Application
    Filed: December 27, 2006
    Publication date: April 3, 2008
    Inventors: Hyung-Do Choi, Dong-Ho Kim, Dong-Uk Sim, Jae-Ick Choi, Ae-Kyoung Lee
  • Patent number: 7106264
    Abstract: The present invention provides a broadband slot array antenna that can be implemented with lower cost by using a single dielectric layer and a metal layer, and makes easy to implement an active integrated antenna. The broadband slot antenna includes: a dielectric layer under which a microstrip feedline is formed; a ground formed on the dielectric layer and electromagnetically coupled with the microstrip antenna through a slot; and a reflection plane placed under the microstrip feedline in order to prevent board surface waves from being radiated and enhance antenna gain.
    Type: Grant
    Filed: August 27, 2003
    Date of Patent: September 12, 2006
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jong Moon Lee, Yong Heui Cho, Jae Ick Choi, Sig Pyo Cheol, Jong-Suk Chae
  • Patent number: 7099631
    Abstract: The present invention relates to a structure of an antenna and its shielding structure for a mobile phone which may significantly reduce the hazardous electromagnetic wave transmitted to the user's body. The present invention arranges a monopole antenna inside of the mobile phone housing, and installs an electromagnetic wave absorber between the antenna and the circuit board. The electromagnetic wave absorber can absorb the electromagnetic wave reflected form conductive plate constituting the circuit board. Thus, the adverse effect of the reflected electromagnetic wave to the performance of antenna is prevented and the amount of the electromagnetic wave to which the users is exposed can be significantly reduced as well.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: August 29, 2006
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Tae Yune Lee, Je Hoon Yun, Jae Ick Choi, Jong Hwa Kwon, Hyun Ho Park
  • Patent number: 7057572
    Abstract: A horn antenna system having a strip line feeding structure of which size is reduced while cross polarized characteristics are kept. The horn antenna system, includes: a first horn antenna unit having a first horn antenna and a first ground made of metal, for radiating a signal; a second horn antenna unit having a second horn antenna and a second ground made of metal, for reflecting the signal to allow the second horn antenna unit to radiate the signal; and a feeding unit located between the first horn antenna unit and the second horn antenna unit, for feeding the energy to the first horn antenna unit and the second horn antenna unit, wherein the feeding unit is a stripe line.
    Type: Grant
    Filed: November 3, 2003
    Date of Patent: June 6, 2006
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Tae Yune Lee, Nak Seon Seong, Ji-Hoon Bae, Jong Suk Chae, Jae Ick Choi
  • Patent number: 6965345
    Abstract: Provided is a method for designing multiband antenna using a genetic algorithm unit linked to an electromagnetic wave analyzing unit and to a computer-readable recording medium for recording a program that implements the method. The multiband antenna designing method can design an antenna having an optimal structure by combining a genetic algorithm, one of global optimization techniques, with a full electromagnetic wave analyzing program Quick Finite Difference Time Domain (QFDTD).
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: November 15, 2005
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ji-Hoon Bae, Cheol-Sig Pyo, You-Chung Chung, Jeong-Il Kim, Jae-Ick Choi, Chang-Joo Kim
  • Patent number: 6946995
    Abstract: The present invention provides a microstrip patch antenna and array antenna using dielectric superstrate in order to enhance the antenna gain by stacking radiating patches and dielectric layers. The microstrip patch antenna using a dielectric superstrate for having high gain and wide bandwidth, includes: a lower patch antenna layer having a dielectric layer and a ground plane for radiating energy by exciting current by a feedline; a upper patch antenna layer having dielectric film electromagnetically coupled by the lower radiating patch; a foam layer for distancing the upper patch antenna layer from the lower patch antenna layer; and a dielectric superstrate located by being predeteremined distant from the upper patch antenna layer.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: September 20, 2005
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Won Kyu Choi, Sig Pyo Cheol, Jong Moon Lee, Young Keun Yoon, Yong Heui Cho, Jong-Suk Chae, Jae Ick Choi
  • Publication number: 20050088343
    Abstract: Provided is a method for designing multiband antenna using a genetic algorithm unit linked to an electromagnetic wave analyzing unit and to a computer-readable recording medium for recording a program that implements the method. The multiband antenna designing method can design an antenna having an optimal structure by combining a genetic algorithm, one of global optimization techniques, with a full electromagnetic wave analyzing program Quick Finite Difference Time Domain (QFDTD).
    Type: Application
    Filed: April 22, 2004
    Publication date: April 28, 2005
    Inventors: Ji-Hoon Bae, Cheol-Sig Pyo, You-Chung Chung, Jeong-Il Kim, Jae-Ick Choi, Chang-Joo Kim
  • Publication number: 20040169604
    Abstract: The present invention provides a broadband slot array antenna that can be implemented with lower cost by using a single dielectric layer and a metal layer, and makes easy to implement an active integrated antenna. The broadband slot antenna includes: a dielectric layer under which a microstrip feedline is formed; a ground formed on the dielectric layer and electromagnetically coupled with the microstrip antenna through a slot; and a reflection plane placed under the microstrip feedline in order to prevent board surface waves from being radiated and enhance antenna gain.
    Type: Application
    Filed: August 27, 2003
    Publication date: September 2, 2004
    Inventors: Jong Moon Lee, Yong Heui Cho, Jae Ick Choi, Sig Pyo Cheol, Jong-Suk Chae
  • Publication number: 20040104852
    Abstract: The present invention provides a microstrip patch antenna and array antenna using dielectric superstrate in order to enhance the antenna gain by stacking radiating patches and dielectric layers. The microstrip patch antenna using a dielectric superstrate for having high gain and wide bandwidth, includes: a lower patch antenna layer having a dielectric layer and a ground plane for radiating energy by exciting current by a feedline; a upper patch antenna layer having dielectric film electromagnetically coupled by the lower radiating patch; a foam layer for distancing the upper patch antenna layer from the lower patch antenna layer; and a dielectric superstrate located by being predeteremined distant from the upper patch antenna layer.
    Type: Application
    Filed: August 8, 2003
    Publication date: June 3, 2004
    Inventors: Won Kyu Choi, Sig Pyo Cheol, Jong Moon Lee, Young Keun Yoon, Yong Heui Cho, Jong-Suk Chae, Jae Ick Choi
  • Publication number: 20040095286
    Abstract: A horn antenna system having a strip line feeding structure of which size is reduced while cross polarized characteristics are kept. The horn antenna system, includes: a first horn antenna unit having a first horn antenna and a first ground made of metal, for radiating a signal; a second horn antenna unit having a second horn antenna and a second ground made of metal, for reflecting the signal to allow the second horn antenna unit to radiate the signal; and a feeding unit located between the first horn antenna unit and the second horn antenna unit, for feeding the energy to the first horn antenna unit and the second horn antenna unit, wherein the feeding unit is a stripe line.
    Type: Application
    Filed: November 3, 2003
    Publication date: May 20, 2004
    Inventors: Tae Yune Lee, Nak Seon Seong, Ji-Hoon Bae, Jong Suk Chae, Jae Ick Choi
  • Publication number: 20040023682
    Abstract: The present invention relates to a structure of an antenna and its shielding structure for a mobile phone which may significantly reduce the hazardous electromagnetic wave transmitted to the user's body. The present invention arranges a monopole antenna inside of the mobile phone housing, and installs an electromagnetic wave absorber between the antenna and the circuit board. The electromagnetic wave absorber can absorb the electromagnetic wave reflected form conductive plate constituting the circuit board. Thus, the adverse effect of the reflected electromagnetic wave to the performance of antenna is prevented and the amount of the electromagnetic wave to which the users is exposed can be significantly reduced as well.
    Type: Application
    Filed: March 4, 2003
    Publication date: February 5, 2004
    Inventors: Tae Yune Lee, Je Hoon Yun, Jae Ick Choi, Jong Hwa Kwon, Hyun Ho Park
  • Patent number: 6683566
    Abstract: Disclosed is an electronic active phase control array antenna having two beams which comprises: a first array unit for performing phase shifting on radio waves received via satellite communication, combining them, and generating first beams on the basis of a first phase delay control value according to a first beam frequency; and a second array unit for performing phase shifting on the output value phase-shifted by the first array unit on the basis of a second phase delay control value for compensating for the phase delay difference according to a second beam frequency shifted through the first array unit, and generating second beams.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: January 27, 2004
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Soon-Ik Jeon, Seong-Ho Son, Jae-Ick Choi
  • Publication number: 20030122709
    Abstract: Disclosed is an electronic active phase control array antenna having two beams which comprises: a first array unit for performing phase shifting on radio waves received via satellite communication, combining them, and generating first beams on the basis of a first phase delay control value according to a first beam frequency; and a second array unit for performing phase shifting on the output value phase-shifted by the first array unit on the basis of a second phase delay control value for compensating for the phase delay difference according to a second beam frequency shifted through the first array unit, and generating second beams.
    Type: Application
    Filed: June 28, 2002
    Publication date: July 3, 2003
    Inventors: Soon-Ik Jeon, Seong-Ho Son, Jae-Ick Choi
  • Patent number: 6438361
    Abstract: An apparatus, method and readable medium capable of automatically selecting a channel of a broadband frequency and calibrating a frequency change using approximated frequency mapping function are disclosed. The apparatus comprises a frequency band dividing part; a frequency converting part; a first controlling part; and a second controlling part. The second controlling part selects a coefficient of an approximated frequency mapping function for a channel corresponding to a channel conversion selection signal from outside from previously stored coefficients of approximated frequency mapping function for the divided frequency.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: August 20, 2002
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Young Jun Chong, Jae Young Kim, Sung Choon Kang, Jae Ick Choi, Jae Hong Park
  • Patent number: 6232837
    Abstract: Provided with an optimal control method for an adaptive feedforward linear amplifier that includes an adaptive controller connected to first and second PLLs (Phase Locked Loops) respectively determining frequency bands for a main signal component and a distortion signal component. The adaptive controller adaptively controls control voltages of a first variable phase shifter and a first variable attenuator constituting a main signal cancellation loop and control voltages of a second variable phase shifter and a second variable attenuator constituting an error signal cancellation loop.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: May 15, 2001
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ki Suk Yoo, Sang Gee Kang, Jae Ick Choi, Jong Suk Chae
  • Patent number: 6124832
    Abstract: This invention relates to a structure of an active antenna system of a mobile and a satellite navigation method using the system. The present invention provides a structure of an active antenna system of a mobile and a satellite tracking method using the system, in which beams are formed and then directed by using sub-array concept, the tracking accuracy becomes to high by using double beam satellite tracking mode for tracking the satellite, tracking loss is reduced and positions are more accurately tracked during movement using an absolute steering sensing mode.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: September 26, 2000
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Soon Ik Jeon, Soon Young Eom, Cheol Sig Pyo, Jae Ick Choi, Choon Sik Yim