Patent ID: 8710924

Claim:
An amplifier comprising a plurality of Doherty amplifier cells, each Doherty amplifier cell comprising: an input and an output respectively connected to an input and an output of the amplifier; a main amplifier stage; a peak amplifier stage; a signal combining circuit configured to combine signals from outputs of the main and peak amplifiers and provide a combined signal to the output of the Doherty amplifier cell; a control circuit configured to determine an amplitude of a signal at the input or output of the amplifier and provide a splitter control signal to each controllable splitter in response to the signal amplitude; and a controllable input power splitter having an input connected to the input of the Doherty amplifier cell, wherein the controllable input power splitter is configured to modify an amplitude and phase of a signal at the input of the Doherty amplifier cell in response to a received splitter control signal and provide a first modified signal to the input of the main amplifier stage and a second modified signal to the input of the peak amplifier stage.