Patent ID: 6853245
Filing Date: 2005-02-08
Classification: H03F

Abstract:
1. A Doherty amplifier comprising: N ways, where N≧2 and N is a natural number; a carrier amplifier which is placed on one of the N ways; peak amplifiers which are placed on respective ways of the (N−1) ways excluding the way on which the carrier amplifier is placed; a power distribution unit which distributes power to each of the N ways; a first offset line located at the output of the carrier amplifier and having a characteristic impedance R a second offset line located at the output of the peak amplifiers and having a characteristic impedance R a transmission line having a phase angle of 90°+θ a quarter wave impedance transformer at which the N ways meet an having a characteristic impedance R and R O is output load resistance at the output of the quarter wave impedance transformer.