FEED FORWARD AMPLIFIER PREVENTING SPURIOUS OUTPUT AT INITIAL OPERATION TIME

摘要

PURPOSE:To eliminate a switch, to reduce power loss from the output of a main amplifier to the output of a device and to reduce the power consumption of an amplifier by controlling output during an initial operation in the poststage of the main amplifier with respect to a feed forward amplifier of spurious wave output prevention an initial operation time, which is suitable for a radio transmission-reception device in a radio communication system. CONSTITUTION:The result detected for a power startup detection means 8 and a main signal detection means 9 are used as timing information. Pilot signal attenuation quantity by a pilot signal variable attenuation part 5 is gradually reduced after the power of the main amplifier 1 is supplied. A control part 7 for controlling the pilot signal variable attenuation part 5 and the main signal variable attenuation part 6 so that main signal attenuation quantity by the main signal variable attenuation part 6 is gradually reduced after pilot signal attenuation quantity by the pilot signal variable attenuation part 5 is reduced is provided.