公开(公告)号：EP0911985A3

公开(公告)日：2002-10-02

申请号：EP98119696.7

申请日：1998-10-19

申请人： MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.

发明人： Matsuura, Toru ,  Ishida, Kaoru ,  Kosugi, Hiroaki ,  Morinaga, Youichi Foyuhiro-Saidoterasu

IPC分类号： H04B1/04 ,  H04B1/40

CPC分类号： H04B1/0458 ,  H03F1/56 ,  H03F3/193 ,  H03F3/245 ,  H03F2200/111 ,  H03F2200/387 ,  H04B1/006

摘要： Disclosed is a transmitter for switching and transmitting signals of plural frequency bands. For example, the signals of two frequency bands are switched and transmitted. For the transmission in a first frequency band, both of transistors 104, 105 are turned off, whereby a power amplifying transistor 102 is matched by an input wide band matching circuit 101 and an output main matching circuit 103, so that the high efficiency linear amplification is accomplished. For the transmission in a second frequency band, the transistor 104 is turned on while the transistor 105 is turned off, whereby the power amplifying transistor 102 is matched by a capacitance 108 as well as the input wide band matching circuit 101 and the output main matching circuit 103, so that the high efficiency linear amplification is accomplished. An external switch for switching the matching circuits is thus unnecessary.