Matsushita Electric Industrial Co., Ltd.

Toyota Motor Corporation

Noise Laboratory Co., Ltd.

Hisashi Morishita

Yoshio Koyanagi

Takayuki Kubo

Kyohei Fujimoto

Toru Uno

Takeshi Ishida

Hiroki Keino

Keigo Yuba

Taro Yamasaki

Jun Ito

Masao Sakuma

Akihiko Nojima

[Problem to be Solved] To provide an antenna which can be used in a wide band. [Solution] An antennaA includes a dielectric substrate, an unbalanced power supply memberhaving a non-power supply unitand a power supply unit, a resonance conductorhaving a connection area, a first resonance areaand a second resonance area, a grounding conductorhaving a first ground areaand a second ground area, and a radiation conductorhaving a first radiation areaand a second radiation area. At the antennaA, first to third radiation stepped portionstoare formed at a first rear end portionof the second radiation area, and first to third radiation stepped portionstoare formed at a second rear end portionof the second radiation area

Antenna

A one-wavelength loop antenna element ( ) shaped like a rectangle is placed close to a radio base plate ( ) 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 ( ), so that the current component flowing onto the top of the radio base plate ( ) 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.

Antenna apparatus

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 ( ), ( ) connected to a balanced feeding line ( ), the helical antenna elements having antenna axes in a direction parallel to a base plate ( ) 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.

Antenna unit

Growing community of inventors

Kanagawa, Japan

Hisashi Morishita