Abstract: A microwave Doherty amplifier employs a way-extension in which N ways (N?2, N is a natural number) are established, and envelope tracking for high efficiency and linearity of the power amplifier of a mobile communications base station or of a handset with improved reliability. The Doherty amplifier includes 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; and a quarter wave impedance transformer at which the N ways meet.