METHOD AND APPARATUS FOR REMOVING PASSIVE IMD

摘要

PURPOSE: A method and an apparatus for removing passive IMD(Inter Modulation Distortion) are provided to remove passive IMD generated at a band-pass filter by using modified feed forward linear amplification units. CONSTITUTION: FA1(Frequency Assignment)(311), FA2(312), FA3(313) and FA4(314) as four frequency allocation signals, are mixed/distributed at a power mixing and distributor(320) and thereafter the distributed signals are applied to input terminals of feed forward linear amplification units(331-334). The units(331-334) amplify four channel signals without distortion and the amplified signals are mixed at a first power mixer(340). The output signal of the first power mixer(340) is applied to a band-pass filter(350). Manual cross modulation components produced from the respective feed forward linear amplification units(331-334) are mixed at a second power mixer(380) and thereafter the output signal of the second power mixer is applied to a first power combiner(360).