| 摘要 |
PROBLEM TO BE SOLVED: To provide an inverted-F antenna that is applicable to a plurality of frequency bands or a broad frequency band. SOLUTION: An antenna sections 1 has a feeding terminal connected to a radiation element 2 and frequency changeover terminals 5, 6. The frequency changeover terminals 5, 6 are respectively connected to switches 7, 9 controlled by a control circuit 13, and the frequency changeover terminals 6 is connected directly or via an inductor 8 to a ground plate 3. Thus, the resonance frequency is selected. Furthermore, the switch 9 allows the frequency changeover terminal 7 to be connected with or to be opened from the ground plate 3 so as to switch the resonance frequency of the inverted-F antenna. Since the inductor or the like can change the resonance frequency, the frequency can be changed by a small frequency step and adjacent frequencies can be selected optionally. |
