Patents by Inventor Tatsuya Fukunaga

Tatsuya Fukunaga 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: 7561012
    Abstract: A pair of balanced terminals is connected to a pair of interdigital-coupled quarter-wave resonators in an electronic device. This electronic device has a first resonance mode that resonates at a first resonance frequency f1 higher than a resonance frequency f0 in each of the pair of quarter-wave resonators when establishing no interdigital-coupling, and a second resonance mode that resonates at a second resonance frequency f2 lower than the resonance frequency f0. The second resonance frequency f2 of a low frequency is set as an operating frequency. This provides an electronic device and a filter that facilitate miniaturization and enable a balanced signal to be transmitted with superior balance characteristics.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: July 14, 2009
    Assignee: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Patent number: 7541896
    Abstract: A stacked resonator and a filter are provided which are capable of achieving miniaturization and minimum loss, and also capable of transmitting a balanced signal with superior balance characteristics. There are provided a pair of quarter-wave resonators which are interdigital-coupled to each other. One quarter-wave resonator is constructed of a plurality of conductor lines which are stacked and arranged so as to establish a comb-line coupling. By the stacked arrangement so as to establish a comb-line coupling of the plurality of conductor lines, the conductor thickness of this quarter-wave resonator can be increased virtually thereby reducing the conductor loss. Similarly, the other quarter-wave resonator is constructed of a plurality of conductor lines stacked and arranged so as to establish a comb-line coupling, and hence the conductor thickness of this quarter-wave resonator can be increased virtually thereby reducing the conductor loss.
    Type: Grant
    Filed: March 1, 2007
    Date of Patent: June 2, 2009
    Assignee: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Patent number: 7525401
    Abstract: A stacked filter includes an array of resonant sections, the resonant sections adjacent each other being electromagnetically coupled, a first resonator electromagnetically coupled to the resonant section on one end of the array of the resonant sections, and a second resonator electromagnetically coupled to the resonant section on the other end thereof. Each of the resonant sections has a pair of interdigital coupled quarter-wave resonators, and a passing frequency as a filter is set to a value f2 lower than a frequency f0 determined by a physical length ?0/4 of the quarter-wave resonator. The first and second resonators have a physical length of ?2/4, where ?2 is a wavelength corresponding to the passing frequency f2. The stacked filter enables miniaturization and sufficient impedance matching with external circuits in a broad band, resulting in excellent filter characteristics in the broad band.
    Type: Grant
    Filed: September 24, 2007
    Date of Patent: April 28, 2009
    Assignee: TDK Corporation
    Inventors: Toshiyuki Abe, Tatsuya Fukunaga
  • Publication number: 20090085693
    Abstract: A filter being small and having a narrowband filter characteristic is achieved using interdigital-coupled resonators. A first resonator and a second resonator are configured using interdigital-coupled quarter-wavelength resonators respectively. In addition, the first resonator and the second resonator are disposed so as to extend along directions intersecting with each other at a predetermined angle ?. Thus, coupling between the resonators is reduced compared with, for example, a case that the first resonator and the second resonator are, as a whole, disposed in parallel to each other. The angle ?, with which the first resonator and the second resonator are disposed respectively, is adjusted, thereby coupling between the resonators may be made into a desired state. Thus, a desired narrowband filter characteristic is obtained.
    Type: Application
    Filed: September 24, 2008
    Publication date: April 2, 2009
    Applicant: TDK CORPORATION
    Inventor: Tatsuya Fukunaga
  • Patent number: 7495533
    Abstract: The present invention provides a waveguide for the TM mode having a simpler configuration. The waveguide has: a pair of main ground electrodes (2a) and (2b) disposed so as to face each other in parallel with each other with a dielectric block (4) in between; and a pair of side walls (3a) and (3b), each constructed of a plurality of sub ground electrodes (11) provided between the pair of main ground electrodes (2a) and (2b), the sub ground electrodes (11) stacked in parallel with the main ground electrodes (2a) and (2b) with a interval along a direction orthogonal to the main ground electrodes (2a) and (2b). Electromagnetic waves in the TM mode may propagate in a region (5) surrounded by the pair of main ground electrodes (2a) and (2b) and the pair of side walls (3a) and (3b).
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: February 24, 2009
    Assignee: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Patent number: 7495528
    Abstract: The present invention provides a triplexer circuit obtaining an impedance matching in each of frequency bands with a simple configuration and separating a signal excellently. Three filters are connected in parallel with each other and, for signals in a pass frequency band of one of the filters, the other two filters form a parallel resonant circuit. In this case, the total impedance of the whole parallel resonant circuit becomes infinite (?) and the other two filters can be made open to the pass frequency band of the one filter. With the simple configuration in which the three filters are connected in parallel with each other, an impedance matching is obtained in each of the frequency bands, and excellent signal separation can be performed.
    Type: Grant
    Filed: May 18, 2006
    Date of Patent: February 24, 2009
    Assignee: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Publication number: 20090021324
    Abstract: The present invention provides an RF module capable of converting electromagnetic waves in the TE mode to balanced electromagnetic waves in the TEM mode without adjustment and outputting the balanced electromagnetic waves while easily realizing miniaturization. The RF module includes: a waveguide (3) in which a half-wavelength TE mode resonator (2) is formed; an E plane coupling window (4) formed in a wall portion (3a) orthogonal to an H plane out of wall portions (3a) to (3e) constructing the TE mode resonator (2) in the waveguide (3); an output line (5a) provided at the edge on the side of the wall portion (3d) parallel with the H plane on the E plane coupling window (4), and magnetically coupled to electromagnetic waves in the TE mode resonator (2); and another output line (5b) provided at the edge on the side of the wall portion (3e) parallel with the H plane in the E plane coupling window (4), and magnetically coupled to the electromagnetic waves.
    Type: Application
    Filed: September 15, 2008
    Publication date: January 22, 2009
    Applicant: TDK CORPORATION
    Inventors: Tatsuya Fukunaga, Masaaki Ikeda, Kiyoshi Hatanaka
  • Patent number: 7439829
    Abstract: The present invention provides an RF module capable of converting electromagnetic waves in the TE mode to balanced electromagnetic waves in the TEM mode without adjustment and outputting the balanced electromagnetic waves while easily realizing miniaturization. The RF module includes: a waveguide (3) in which a half-wavelength TE mode resonator (2) is formed; an E plane coupling window (4) formed in a wall portion (3a) orthogonal to an H plane out of wall portions (3a) to (3e) constructing the TE mode resonator (2) in the waveguide (3); an output line (5a) provided at the edge on the side of the wall portion (3d) parallel with the H plane on the E plane coupling window (4), and magnetically coupled to electromagnetic waves in the TE mode resonator (2); and another output line (5b) provided at the edge on the side of the wall portion (3e) parallel with the H plane in the E plane coupling window (4), and magnetically coupled to the electromagnetic waves.
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: October 21, 2008
    Assignee: TDK Corporation
    Inventors: Tatsuya Fukunaga, Masaaki Ikeda, Kiyoshi Hatanaka
  • Patent number: 7403085
    Abstract: The present invention provides an RF module capable of outputting balanced electromagnetic waves without requiring adjustment and easily realizing miniaturization. The RF module includes: a waveguide (3) having an area which is surrounded by a pair of ground electrodes (6) and (7) provided so as to face each other and through holes (8) for making electric conduction between the pair of ground electrodes (6) and (7) and in which electromagnetic waves in the TE mode can propagate and a one-wavelength resonator (11) is formed; and a pair of output lines (4a) and (4b) connected to portions corresponding to half-wavelength resonance regions (A) and (B) of the one-wavelength resonator (11) in the ground electrode (6).
    Type: Grant
    Filed: March 31, 2004
    Date of Patent: July 22, 2008
    Assignee: TDK Corporation
    Inventors: Tatsuya Fukunaga, Masaaki Ikeda, Kiyoshi Hatanaka
  • Publication number: 20080079517
    Abstract: A stacked filter includes an array of resonant sections, the resonant sections adjacent each other being electromagnetically coupled, a first resonator electromagnetically coupled to the resonant section on one end of the array of the resonant sections, and a second resonator electromagnetically coupled to the resonant section on the other end thereof. Each of the resonant sections has a pair of interdigital coupled quarter-wave resonators, and a passing frequency as a filter is set to a value f2 lower than a frequency f0 determined by a physical length ?0/4 of the quarter-wave resonator. The first and second resonators have a physical length of ?2/4, where ?2 is a wavelength corresponding to the passing frequency f2. The stacked filter enables miniaturization and sufficient impedance matching with external circuits in a broad band, resulting in excellent filter characteristics in the broad band.
    Type: Application
    Filed: September 24, 2007
    Publication date: April 3, 2008
    Applicant: TDK CORPORATION
    Inventors: Toshiyuki Abe, Tatsuya Fukunaga
  • Publication number: 20070205851
    Abstract: A stacked resonator and a filter are provided which are capable of achieving miniaturization and minimum loss, and also capable of transmitting a balanced signal with superior balance characteristics. There are provided a pair of quarter-wave resonators which are interdigital-coupled to each other. One quarter-wave resonator is constructed of a plurality of conductor lines which are stacked and arranged so as to establish a comb-line coupling. By the stacked arrangement so as to establish a comb-line coupling of the plurality of conductor lines, the conductor thickness of this quarter-wave resonator can be increased virtually thereby reducing the conductor loss. Similarly, the other quarter-wave resonator is constructed of a plurality of conductor lines stacked and arranged so as to establish a comb-line coupling, and hence the conductor thickness of this quarter-wave resonator can be increased virtually thereby reducing the conductor loss.
    Type: Application
    Filed: March 1, 2007
    Publication date: September 6, 2007
    Applicant: TDK CORPORATION
    Inventor: Tatsuya Fukunaga
  • Publication number: 20070171005
    Abstract: Provided are a stacked resonator capable of achieving miniaturization and minimum loss, and a stacked resonator capable of suppressing any unnecessary resonance mode due to interdigital-coupling. The stacked resonator includes a first conductor group having a plurality of conductor lines in a stacking arrangement, and a second conductor group having a plurality of other conductor lines in a stacking arrangement so as to be alternately provided opposing to the conductor lines in the first conductor group, thereby establishing an interdigital-coupling together with the first conductor group.
    Type: Application
    Filed: January 23, 2007
    Publication date: July 26, 2007
    Applicant: TDK CORPORATION
    Inventor: Tatsuya Fukunaga
  • Publication number: 20070159277
    Abstract: The present invention provides a waveguide for the TM mode having a simpler configuration. The waveguide has: a pair of main ground electrodes (2a) and (2b) disposed so as to face each other in parallel with each other with a dielectric block (4) in between; and a pair of side walls (3a) and (3b), each constructed of a plurality of sub ground electrodes (11) provided between the pair of main ground electrodes (2a) and (2b), the sub ground electrodes (11) stacked in parallel with the main ground electrodes (2a) and (2b) with a interval along a direction orthogonal to the main ground electrodes (2a) and (2b). Electromagnetic waves in the TM mode may propagate in a region (5) surrounded by the pair of main ground electrodes (2a) and (2b) and the pair of side walls (3a) and (3b).
    Type: Application
    Filed: January 25, 2005
    Publication date: July 12, 2007
    Applicant: TDK CORPORATION
    Inventor: Tatsuya Fukunaga
  • Patent number: 7227428
    Abstract: The present invention is directed to enable mode conversion between a TEM mode and another mode to be performed among a plurality of waveguides. An RF module comprises: a microstrip line as a first waveguide for propagating electromagnetic waves in a TEM mode; and a waveguide having a multilayer structure as a second waveguide connected to the first waveguide, for propagating electromagnetic waves in another mode different from the TEM mode. An end of the first waveguide is directly or indirectly connected so as to be conductive to one of ground electrodes of the second waveguide from the direction orthogonal to the stacking direction of the ground electrodes. Since magnetic fields are coupled so that the direction of the magnetic field of the first waveguide and that of the magnetic field of the second waveguide match with each other in the E plane, mode conversion between the TEM mode and another mode to be excellently performed between the waveguides.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: June 5, 2007
    Assignee: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Patent number: 7199996
    Abstract: A laminated capacitor includes a capacitor body and first, second, third and fourth external electrodes disposed on an external surface of the capacitor body. The capacitor body has first and second electrode patterns that are alternately laminated with dielectric layers between. The first electrode pattern provides a first internal electrode that is connected to both the first and second external electrodes. The second electrode pattern provides second and third internal electrodes. The second internal electrode is connected to both the third and fourth external electrodes. The third internal electrode is disposed in the same layer as the second internal electrode and connected to one of the third and fourth external electrodes.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: April 3, 2007
    Assignee: TDK Corporation
    Inventors: Masaaki Togashi, Tatsuya Fukunaga
  • Patent number: 7199680
    Abstract: The present invention is directed to enable mode conversion between a TEM mode and another mode to be performed among a plurality of waveguides. An RF module comprises: a TEM waveguide as a first waveguide for propagating electromagnetic waves in a TEM mode; and a waveguide having a multilayer structure as a second waveguide connected to the first waveguide, for propagating electromagnetic waves in another mode different from the TEM mode. An end of the first waveguide is directly conductively connected to one of ground electrodes of the second waveguide from the stacking direction side of the ground electrodes. Since magnetic fields are coupled so that the direction of the magnetic field of the first waveguide and that of the magnetic field of the second waveguide match with each other in the H plane, mode conversion between the TEM mode and another mode can be excellently performed between the waveguides.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: April 3, 2007
    Assignee: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Publication number: 20070024398
    Abstract: A pair of balanced terminals is connected to a pair of interdigital-coupled quarter-wave resonators in an electronic device. This electronic device has a first resonance mode that resonates at a first resonance frequency f1 higher than a resonance frequency f0 in each of the pair of quarter-wave resonators when establishing no interdigital-coupling, and a second resonance mode that resonates at a second resonance frequency f2 lower than the resonance frequency f0. The second resonance frequency f2 of a low frequency is set as an operating frequency. This provides an electronic device and a filter that facilitate miniaturization and enable a balanced signal to be transmitted with superior balance characteristics.
    Type: Application
    Filed: July 27, 2006
    Publication date: February 1, 2007
    Applicant: TDK Corporation
    Inventor: Tatsuya Fukunaga
  • Publication number: 20060284704
    Abstract: The present invention provides an RF module capable of outputting balanced electromagnetic waves without requiring adjustment and easily realizing miniaturization. The RF module includes: a waveguide (3) having an area which is surrounded by a pair of ground electrodes (6) and (7) provided so as to face each other and through holes (8) for making electric conduction between the pair of ground electrodes (6) and (7) and in which electromagnetic waves in the TE mode can propagate and a one-wavelength resonator (11) is formed; and a pair of output lines (4a) and (4b) connected to portions corresponding to half-wavelength resonance regions (A) and (B) of the one-wavelength resonator (11) in the ground electrode (6).
    Type: Application
    Filed: March 31, 2004
    Publication date: December 21, 2006
    Applicant: TDK Corporation
    Inventors: Tatsuya Fukunaga, Masaaki Ikeda, Kiyoshi Hatanaka
  • Publication number: 20060279903
    Abstract: A laminated capacitor includes a capacitor body and first, second, third and fourth external electrodes disposed on an external surface of the capacitor body. The capacitor body has first and second electrode patterns that are alternately laminated with dielectric layers between. The first electrode pattern provides a first internal electrode that is connected to both the first and second external electrodes. The second electrode pattern provides second and third internal electrodes. The second internal electrode is connected to both the third and fourth external electrodes. The third internal electrode is disposed in the same layer as the second internal electrode and connected to one of the third and fourth external electrodes.
    Type: Application
    Filed: May 25, 2006
    Publication date: December 14, 2006
    Applicant: TDK Corporation
    Inventors: Masaaki Togashi, Tatsuya Fukunaga
  • Publication number: 20060268811
    Abstract: The present invention provides a triplexer circuit obtaining an impedance matching in each of frequency bands with a simple configuration and separating a signal excellently. Three filters are connected in parallel with each other and, for signals in a pass frequency band of one of the filters, the other two filters form a parallel resonant circuit. In this case, the total impedance of the whole parallel resonant circuit becomes infinite (?) and the other two filters can be made open to the pass frequency band of the one filter. With the simple configuration in which the three filters are connected in parallel with each other, an impedance matching is obtained in each of the frequency bands, and excellent signal separation can be performed.
    Type: Application
    Filed: May 18, 2006
    Publication date: November 30, 2006
    Applicant: TDK CORPORATION
    Inventor: Tatsuya Fukunaga