TRANSMISSION OUTPUT CONTROL CIRCUIT AND RADIO EQUIPMENT USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a stable transmission output control circuit widely adaptable to a dynamic range necessary for detecting a transmission output signal level, by using a diode incorporated in a power amplifier unit. SOLUTION: One end of a coupling capacitor 24 and one end of a main line 30 of a directional coupler 28 are connected to an output terminal 29 of a power amplifier 21. In the power amplifier 20, there is provided a switch 33 for connecting the other end of the coupling capacitor 24 and one end of a subline 31 of the directional coupler 28 to either a cathode of the diode 23 or a second termination resistor 35. By switching the switch 33, either the coupling capacitor 24 or the directional coupler 28 is connected. COPYRIGHT: (C)2006,JPO&NCIPI