| 摘要 |
An antenna device for a portable radio communication device operable in at least a first and a second frequency band, includes first and second electrically conductive planar radiating elements. The first radiating element has a feeding portion connectable to a feed device of the portable radio communication device. The second radiating element includes a grounding portion connectable to ground. A controllable switch is arranged between the first and second radiating elements for selectively interconnecting and disconnecting the radiating elements. The state of the switch is controlled by means of a control voltage input. A first filter is arranged between the feeding portion and the control voltage input, to block radio frequency signals. By providing a high pass filter between the first and second radiating elements above a ground plane, quad-band operation is provided with high efficiency in a physically small antenna device. |
