Patents by Inventor Yoshio Koyanagi

Yoshio Koyanagi 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: 6590538
    Abstract: An antenna apparatus which has an antenna element (102) being mounted on a portable radio for receiving electric power from a feeding point (103) in the portable radio and matching in a predetermined frequency band and a matching circuit (104) for matching the impedance of the antenna element (102) and the internal impedance of the radio circuit (105). The matching circuit (104) has a match characteristic to conjugately match the internal impedance of the radio circuit (105) and the input impedance of the matching circuit (104).
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: July 8, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshio Koyanagi, Genji Hirokawa, Koichi Ogawa, Koichi Ito
  • Patent number: 6459412
    Abstract: In an antenna unit adapted to be incorporated inside a main body of a mobile radio set, there are provided a pair of helical antenna elements (102), (103) connected to a balanced feeding line (104), the helical antenna elements having antenna axes in a direction parallel to a base plate (201) of the radio set, and being arranged in proximity to the base plate of the radio set at a sufficiently small distance as compared with their wavelength. By conducting a balanced power supply to the helical antenna elements, an electric current component flowing on the base plate of the radio set can be reduced, thus decreasing influence of the human body when the radio set is carried by the human hand. Additionally, the antenna can posses radiation characteristics of both the electric current type antenna and the magnetic current type antenna, and therefore, the receiving performance when the radio set is tiltedly used will be enhanced.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: October 1, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshio Koyanagi, Hisashi Morishita, Kyohei Fujimoto
  • Publication number: 20020018021
    Abstract: A one-wavelength loop antenna element (103) shaped like a rectangle is placed close to a radio base plate (101) and further is bent at both end parts toward a feeding section, whereby a current distribution where the current at the tip of turn up becomes zero is formed. Current is concentrated on the loop antenna element (103), so that the current component flowing onto the top of the radio base plate (101) is decreased, the effect produced when a human being carries a radio containing an antenna including the loop antenna element is suppressed, and the directivity responsive to an arrival wave is formed.
    Type: Application
    Filed: July 13, 2001
    Publication date: February 14, 2002
    Inventors: Yoshio Koyanagi, Hisashi Morishita, Jun Ito
  • Publication number: 20020013159
    Abstract: In a portable telephone, a main body case and a cover case are connected rotatably by a hinge portion. Further, the main body case is made of a resin material, metal, or a material including metal, and the cover case is made of a metal material. Further, when the portable telephone is used, the cover case is positioned on a side surface of an antenna. Therefore, the current becomes easy to flow, and the current flowing in the main body decreases. Accordingly, the disturbance of the current distribution in case that the main body case is held by the user's hand decreases, so that it is possible to reduce the deterioration of antenna gain.
    Type: Application
    Filed: July 12, 2001
    Publication date: January 31, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsukasa Takahashi, Masayoshi Hirai, Kenichi Yamada, Kazuhiko Ota, Yoshio Koyanagi
  • Publication number: 20010004605
    Abstract: Corresponding to transmission data 101, phase controller 105 is controlled to shift a phase of modulated signal 103 by 0° or 180°. Planes of polarization of modulated signals to be transmitted from antennas 106 and 107 are made different from each other corresponding to transmission data 101. The electric field strength of a signal received at antenna 108 changes corresponding to the plane of polarization, thereby voltage value 113 output from electric field strength detector 111 varies corresponding to transmission data 101, and using this variation, judged result 115 is obtained. Two results, namely, demodulated data 112 and judged result 115 are input to comparing circuit 116, whereby the reception apparatus is capable of obtaining received data 117 with high quality.
    Type: Application
    Filed: December 20, 2000
    Publication date: June 21, 2001
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kantaro Miyano, Youichi Nakagawa, Masahiro Mimura, Makoto Hasegawa, Yoshio Koyanagi
  • Patent number: 6246372
    Abstract: In a state that a whip antenna is contained in a housing of a cellular phone, a minute space is formed between a feeding spring and an attaching member conductive to a helical antenna base portion, so as to generate electrostatic capacitance, which is equivalent to the impedance characteristic of a mono-pole antenna. Then, electrostatic capacitance and a coil portion of a helical antenna constitute an LC series resonance circuit so as to improve the wide band of the helical antenna.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: June 12, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kiyoshi Egawa, Masazumi Yamazaki, Yoshio Koyanagi, Hidehiro Yanagibashi
  • Patent number: 6211830
    Abstract: A radio antenna is disclosed with improvement in a radiation efficiency obtained by changing a directivity pattern of an antenna toward a direction not interfered by an obstacle and thus reducing radio wave interference by the obstacle. A whip antenna is connected to a transceiver unit in a radio set housing through a feeder line. A passive element is grounded to the radio set housing through a load impedance element. The whip antenna changes the horizontal directivity pattern in dependence upon the electromagnetic coupling with the passive element. The passive element operates as a wave director or a reflector for the whip antenna in accordance with the value of the load impedance element. When the passive element operates as a wave director, the radiation becomes much stronger in the direction toward the passive element. On the other hand, when the passive element operates as a reflector, the radiation in the direction away from the passive element becomes much stronger.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: April 3, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kenji Monma, Toshimitsu Matsuyoshi, Koichi Ogawa, Yoshio Koyanagi
  • Patent number: 6147651
    Abstract: The present invention provides an antenna system, which is used for a mobile wireless device and can be accommodated in or withdrawn from a telephone set main unit, whereby element length is shortened and strength is increased while avoiding deterioration of characteristics when the antenna is accommodated in the telephone set main unit. The antenna (40) comprises a helical antenna (41) having a feeding unit (42) and a whip antenna (43) having a feeding unit (44). The whip antenna (43) passes through the helical antenna (41), and the helical antenna (41) and the whip antenna (43) are electrically insulated from each other. Because the whip antenna (43) is designed to pass through the helical antenna (41), an antenna system for mobile wireless communication can be provided, in which element length is shortened and strength is increased.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: November 14, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masazumi Yamazaki, Kouichi Ogawa, Yoshio Koyanagi
  • Patent number: 6078292
    Abstract: A small-sized wireless device has a whip antenna and a receiver for receiving a call. The whip antenna is provided at the upper side of the rear face of the small-sized wireless device body to improve the antenna performance in a state where a person holds the body to communicate. A rib is provided at a portion of the rear face of the small-sized wireless device body in order to prevent the degradation of the antenna characteristics of the whip antenna at the time of placing the small-sized wireless device body on a metal plate and the like. According to such an arrangement, good sensitivity of the whip antenna can be obtained even when the small-sized wireless device body is placed on a metal plate.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: June 20, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshio Koyanagi, Tsukasa Takahashi, Koichi Ogawa
  • Patent number: 5982330
    Abstract: In an antenna apparatus, a monopole antenna element connected to an antenna matching circuit via a first contact 105 when a whip antenna is extended; a helical antenna element connected to the antenna matching circuit via a second contact when the whip antenna is accommodated; and a parasitic helical element disposed in close proximity to the helical antenna element at a spacing which is sufficiently small with respect to the wavelength of a first frequency band of a radio circuit.
    Type: Grant
    Filed: September 15, 1997
    Date of Patent: November 9, 1999
    Assignee: Matsushita Electric Co., Ltd.
    Inventors: Yoshio Koyanagi, Koichi Ogawa, Masazumi Yamazaki
  • Patent number: 5940040
    Abstract: An antenna system comprises:a whip antenna and a built-in antenna for diversity reception;an antenna select switch for selecting one of the antennas and connecting the selected one to a radio circuit; anda transmission line length adjusting circuit, inserted between the antenna select switch and the whip antenna, for controlling a terminal load condition of the whip antenna, when the built-in antenna is connected to the radio circuit.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: August 17, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshio Koyanagi, Tsukasa Takahashi