Abstract:
A frequency stabilization circuit (25) includes four coiled conductors (L1 to L4), the first coiled conductor (L1) and the second coiled conductor (L2) are connected in series to each other, thereby configuring a first series circuit, the third coiled conductor (L3) and the fourth coiled conductor (L4) are connected in series to each other, thereby configuring a second series circuit, the first series circuit is connected between an antenna port and a power feeding port, and the second series circuit is connected between the antenna port and the ground. The first coiled conductor (L1) and the second coiled conductor (L2) are wound so that a first closed magnetic circuit (a loop indicated by a magnetic flux FP12) is configured, and the third coiled conductor (L3) and the fourth coiled conductor (L4) are wound so that a second closed magnetic circuit (a loop indicated by a magnetic flux FP34) is configured.
Abstract:
An antenna device (106) has an antenna element (11) and an impedance converting circuit (25) connected to the antenna element (11). The impedance converting circuit (25) is connected to a power-supply end of the antenna element (11). The impedance converting circuit (25) is interposed between the antenna element (11) and a power-supply circuit (30). The impedance converting circuit (25) has a first inductance element (L1) connected to the power-supply circuit (30) and a second inductance element (L2) coupled to the first inductance element (L1). A first end and a second end of the first inductance element (L1) are connected to the power-supply circuit (30) and the antenna, respectively. A first end and a second end of the second inductance element (L2) are connected to the antenna element (11) and ground, respectively.