Patents by Inventor Hisasuke Sei

Hisasuke Sei 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).

  • Bandpass filter with dielectric resonators
    Patent number: 4626809
    Abstract: A bandpass filter in which a plurality of dielectric resonators are arranged in an array is disclosed. Two metallic posts each having a length which is substantially equal to a quarter of the wavelength of the fundamental frequency (center frequency of the bandpass filter) are arranged one between the dielectric resonator located at one end of the array and an input connector and the other between the dielectric resonator located at the other end of the array and an output connector. This suppresses propagation of spurious modes, particularly propagation at a twice higher frequency than the fundamental frequency.
    Type: Grant
    Filed: September 20, 1985
    Date of Patent: December 2, 1986
    Assignee: NEC Corporation
    Inventors: Motoo Mizumura, Hisasuke Sei