Patents Assigned to Houkou Electric Corporation
  • Patent number: 6414638
    Abstract: Provides an antenna for a radio telephone whereby, in a state wherein the rod-shaped antenna is extended to outside the case of the radio telephone, the effects of the human body are negligible and emission of radio waves at an angle close to the horizontal direction is possible, and in a state wherein the rod-shaped antenna is retracted within the case, no unwanted radiation is produced. For this purpose, a helical antenna 20 having an electrical length of &lgr;/4 and a rod-shaped antenna 10 extendable and retractable with respect to the case through the hollow central portion of the helical antenna 20 and having an electrical length of about 3&lgr;/8 and inductive reactance are electrically coupled by means of an electrostatic coupling portion 30 having capacitive reactance such that, in the state wherein the rod-shaped antenna 10 is extended from the case 50, the inductive reactance of the rod-shaped antenna 10 is cancelled out.
    Type: Grant
    Filed: July 26, 1999
    Date of Patent: July 2, 2002
    Assignee: Houkou Electric Corporation
    Inventor: Yoshimi Egashira