| 摘要 |
PCT No. PCT/JP96/02014 Sec. 371 Date Feb. 25, 1997 Sec. 102(e) Date Feb. 25, 1997 PCT Filed Jul. 19, 1996 PCT Pub. No. WO97/04533 PCT Pub. Date Feb. 6, 1997An antenna switch comprises a first switch device (11) for selectively coupling a common point (e) with a transmit terminal (a) or a receive terminal (c), a second switch device (12) having similar structure to the first switch device (11) for selectively coupling a common point (f) with a first antenna terminal (b) or a second antenna terminal (d), and a filter (13) coupled between the switch devices (11, 12) through capacitors (14, 15). Circuit structure of the first switch device (11) is the same as that of the second switch device (12). Components composing those switch devices are mounted on each layer of a multi-layer substrate with a symmetrical relationship. The number of components is small, and the structure of an antenna switch is simplified. It is used in a portable telephone set for switching transmit/receive operation, and switching antennas.
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