Patents by Inventor Sadahiko Yamashita

Sadahiko Yamashita 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: 4292610
    Abstract: A coaxial cavity resonator comprising an outer conductor and an inner conductor coaxially disposed in the outer conductor with one end of the inner conductor being connected to an end wall of the outer conductor to establish a short-circuit relationship and the other end of the inner conductor being spaced from the other end wall of the outer conductor to establish an open-circuit relationship. An intermediate hollow conductor is disposed coaxially with the inner and outer conductors and encircles a portion of the axial dimension of the inner conductor. The intermediate conductor has a closed end which is connected with the open-circuit end of the inner conductor.
    Type: Grant
    Filed: January 25, 1980
    Date of Patent: September 29, 1981
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4268809
    Abstract: A microwave filter comprising within a conductive casing, a plurality of resonant transmission lines arranged parallel between opposed end walls of the casing, a plurality of shielding members each located between adjacent transmission lines, and a capacitive interstage coupling member disposed transverse to the transmission line. The interstage coupling member comprises a dielectric member and a plurality of conductive regions arranged successively thereon so as to establish capacitive coupling between adjacent conductive regions. Each transmission line is connected at one end to a side wall of the casing and supported at the other end by the dielectric member in electrical contact with a respective one of the conductive regions, whereby the interstage coupling between the transmission lines is provided by the capacitively coupled conductive regions.
    Type: Grant
    Filed: August 31, 1979
    Date of Patent: May 19, 1981
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4254390
    Abstract: A tuning device including a conductive housing in which are suspended a dielectric substrate. A pair of first and second resonant circuits is disposed on the substrate in parallel with each other. Each resonant circuit is formed by an elongated conductive film and a capacitive element. A grounded conductive strip film is provided between the transmission lines of the first and second resonant circuits to reduce the interstage coupling between the two transmission lines with a resultant decrease in spacing between them.
    Type: Grant
    Filed: February 27, 1979
    Date of Patent: March 3, 1981
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Saito, Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4224587
    Abstract: A comb-line bandpass filter comprising an enclosure or outer conductor and a plurality of inner conductors arranged parallel in the outer conductor. Adjacent to one end of each inner conductor a body of dielectric material is attached to provide a larger diameter, lumped capacitance section while providing a lumped inductance section in the remainder of the inner conductor. A conductive layer, conductively coupled to the outer conductor, encircles the dielectric body to act as a shield between adjacent inner conductors so that the coupling between them is concentrated in the inductive section. Overall size of the comb-line filter is reduced by reduction both in axial length of the inner conductors and the spacing between them.
    Type: Grant
    Filed: November 7, 1978
    Date of Patent: September 23, 1980
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4214218
    Abstract: A tuning device including a conductive housing in which is suspended a dielectric substrate. A pair of first and second resonant circuits is disposed on the substrate in parallel with each other. Each resonant circuit is formed by an elongated conductive film and a capacitive element. An image frequency trapping circuit is arranged to intersect one of the transmission lines to absorb the signal at the image frequency. A grounded conductive strip film is provided adjacent to and parallel with each of the transmission lines and so spaced therefrom that the characteristic impedances of the transmission lines are made equal to each other.
    Type: Grant
    Filed: February 27, 1979
    Date of Patent: July 22, 1980
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Saito, Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4214217
    Abstract: A tuning circuit comprises a pair of identical resonant circuits each including a transmission line and a capacitive element, a coupling circuit associated with each transmission line to inject microwave energy into the resonant circuits and extract the tuned energy therefrom. An image trapping circuit is included which comprises a first section which intersects one of the transmission lines and connected to the coupling circuit associated with the intersected transmission line and a second section which extends from the point of connection of the first section with that coupling element to the opposite transmission line in a direction skewed relative to each transmission line. The second section of the image trap circuit provides a smooth interstage coupling between the two transmission lines over a range of resonant frequencies.
    Type: Grant
    Filed: February 14, 1979
    Date of Patent: July 22, 1980
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuo Saito, Sadahiko Yamashita
  • Patent number: 4121182
    Abstract: A first and second strip are provided on a dielectric substrate such that one end of the first strip juxtaposes one end of the second strip and the other end of the first strip juxtaposes the other end of the second strip. A capacitor is provided between the one ends of the first and the second strips and a varactor is provided between the other ends of the first and the second strips.
    Type: Grant
    Filed: February 25, 1977
    Date of Patent: October 17, 1978
    Assignee: Matsushita Electric Industrial Co., Limited
    Inventors: Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4059815
    Abstract: An improved coaxial cavity resonator comprises an enclosed conductor having opposed ends, and a center cylindrical conductor in the enclosed conductor. The center conductor has smaller and larger diameter portions having respective first and second characteristic impedances. The smaller diameter portion is in contact with one end of the enclosed conductor and has a larger characteristic impedance than the larger diameter portion.
    Type: Grant
    Filed: July 30, 1976
    Date of Patent: November 22, 1977
    Assignee: Matsushita Electric Industrial Co., Limited
    Inventors: Mitsuo Makimoto, Sadahiko Yamashita
  • Patent number: 4016568
    Abstract: A beam of diverging electromagnetic radiation of a predetermined frequency is transmitted to a target and the doppler shift of frequency of an echo due to relative movement of the target and a point of reception is detected conventionally by combining the frequency of the echo and the predetermined frequency. The number of cycles within the detected doppler shift frequency is counted to provide a delay to initiate measurement of doppler shift at a preselected angle of incidence of the echo. The effective area of measurement is thus restricted to a narrow region of the beam with the resultant high degree of precision.
    Type: Grant
    Filed: December 31, 1974
    Date of Patent: April 5, 1977
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mistuo Makimoto, Sadahiko Yamashita, Yoshiharu Yano, Junichi Yamamoto