Antenna device and portable radio apparatus

摘要

A small antenna system which is incorporated in a portable radio apparatus and can ensure high antenna performance in a wide frequency band without impairing the design property or the operability and a portable radio apparatus are provided. An antenna device includes an antenna A1 having a resonance characteristic in a first frequency; an antenna A2 having a resonance characteristic in a second frequency and being spaced from the antenna A1 at a predetermined distance; a circuit board P provided in a mobile telephone 10, a wireless section 16 provided on the circuit board P for supplying or receiving high-frequency power; and a high-frequency switch 13 provided on the circuit board P for selecting connection of an output terminal or an input terminal of the wireless section 16 and a feeding point of the antenna A1 or the antenna A2 so that the feeding point of the antenna A1 or the antenna A2 can be switched and connecting to the wireless section 16.