| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a circuit board capable of changing over between transmission and reception of a plurality of communication systems in which frequency-division duplex communication systems and time-division duplex communication systems are mixed while suppressing increase in size of the whole circuit. <P>SOLUTION: A circuit board has an antenna terminal for performing wireless communication of a time-division duplex first communication system and frequency-division duplex second and third communication systems, and a diplexer. A transmission/reception path of the first communication system connected with one branch terminal of the diplexer is switched over between a transmission path and a reception path by using a first FET switch. A signal path connected to the other branch terminal of the diplexer is switched over between transmission/reception paths of the second communication system and the third communication system via a second FET switch. The transmission/reception paths of the second and third communication systems are connected with duplexers respectively. A circuit including the first FET switch and a circuit including the second FET switch are respectively configured by separated modules, and mounted on the circuit board. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
