| 摘要 |
An internal multiband antenna and a radio device intended particularly for small-sized radio devices. The antenna has a relatively wide surface radiator (330), which is electromagnetically connected to the antenna port of the radio device via a separate feed element (320). At least two useful resonances are generated with the aid of the feed element, and at least one inherent resonance of the radiator is also utilized. The radiator has a hole (350), by which one useful additional resonance is generated. An oscillation is excited in the hole by placing the feed element close to its edge and by suitably choosing the locations of the feed point (F) and the shorting point (S) of the feed element. The frequency of the hole resonance is finely tuned by varying the capacitance between the hole's edge and the ground plane at a suitable place (331). An operating band of the antenna can be widened by means of said additional resonance. If a mobile station has a rear display it is possible at the same time to use its hole as a radiator. <IMAGE> |
