| 摘要 |
The invention provides a duplexer (31), comprising: a first frequency variable type filter (45) including a voltage-controllable reactance element (D1, D2, D3 D4) and operative to switch transmitting - receiving frequencies corresponding to a first communication system (GSM); a second frequency variable type filter (46) including a voltage-controllable reactance element (D5, D6, D7, D8) and operative to switch transmitting - receiving frequencies corresponding to a second communication system (DCS); a synthetic circuit (47) electrically connected between one end of said first frequency variable type filter (45) and one end of said second frequency variable type filter (46); an antenna terminal (ANT) electrically connected to said synthetic circuit (47); a first external terminal (P1) electrically connected to the other end of said first frequency variable type filter (45); and a second external terminal (P2) electrically connected to the other end of said second frequency variable type filter (46). <IMAGE> |
