| 摘要 |
<p>The multi-band mobile telephone (1) includes a coil with end connections (3, and 4-1 to 4-n). The first end (3) is connected to the input-output terminal of a transmitter-receiver (9). A series of switches (11-1 to 11-n) are then provided to selectively short circuit the second end of the aerial (4-1 to 4-n) to earth. The multi-band mobile telephone (1) comprises a radiating aerial consisting of a coil with end connections (3, and 4-1 to 4-n). The first end (3) is connected to the input-output terminal of a transmitter-receiver (9). A series of switches (11-1 to 11-n) are then provided to selectively short circuit the second end of the aerial (4-1 to 4-n) to earth. The adjustment achieved by selecting an appropriate short-circuit point changes the aerial from operating in a quarter wave mode, to operating in a half wave mode. The frequency achieved in the second band position is of the order of twice that achieve in the first band position. -</p> |
