To provide an antenna device which easily matches a circuit to be connected in a post stage of the antenna device 7 in a primary resonance frequency band and tertiary resonance frequency band.
The antenna device 7 to achieve the purpose has: a ground 8; a power feeder 9 formed on the ground 8; a first conductor 10 connected to the power feeder 9; and a second conductor 11 connected to the ground 8 arranged in parallel to the first conductor 10 with a predetermined interval, and having substantially the same conductor length as the conductor length of the first conductor 10. The first conductor 10 and the second conductor 11 are electrically coupled to each other between at least a front end 12 of each of them and a portion 13 of about 1/3 of the conductor length from the front end of each of them.
COPYRIGHT: (C)2007,JPO&INPIT
IGUCHI AKIHIKO
SATOU HIROKI
Hiroki Naito
Daisuke Nagano