| 摘要 |
PROBLEM TO BE SOLVED: To make satisfactory the broadcasting reception sensitivity of both AM and FM broadcasting bands by setting a receiver input impedance value, an antenna conductor output impedance value and a coaxial cable impedance value of the AM/FM broadcasting band within specified ranges. SOLUTION: An antenna conductor 4 and a power feeding point 6 of the antenna conductor 4 are provided on a window glass pane 1 at the rear part of an automobile. The AM and FM broadcasting band received signals of the power feeding point 6 are inputted through a coaxial cable 15 to a receiver 20. The reception input of the AM broadcasting band, the output of the antenna conductor and the impedance of the coaxial cable are respectively made into 500Ω-20Ω, 500Ω-20Ωand 100Ω-500Ωand impedance matching between the side of the antenna and the side of the receiver 20 is attained. On the FM broadcasting band, a reception input impedance is made into 100Ω-1 kΩ, transmission efficiency is improved and the antenna conductor output and the impedance of the coaxial cable are respectively made into 100Ω-500Ω.
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