| 摘要 |
A portable radio apparatus includes an antenna, a transmission/reception circuit, a first matching circuit, a second matching circuit, and a first switch. The antenna consists of a linear element portion constituting a whip antenna and a helical coil portion constituting a helical antenna fixed to a distal end of the linear element portion through an insulating portion. The antenna is supported to be extendible from a housing. The transmission/reception circuit is connected to the helical coil portion in an antenna accommodation state and connected to the linear element portion in an antenna extension state. The first matching circuit performs impedance matching between the helical coil portion and the transmission/reception circuit. The second matching circuit performs impedance matching between the linear element portion and the transmission/reception circuit. The first switch connects the helical coil portion to the first matching circuit in the antenna accommodation state and connects the linear element portion to the second matching circuit in the antenna extension state.
|
