A postdistortion linearizer using diode mixer for improving intermodulation distortion of power amplifier

摘要

PURPOSE: A post-distortion linear power amplifier is provided to improve power loss and efficiency according to a delay line which selects inter-modulation components at a rear stage of the power amplifier, and to compensate distortion properties of a main amplifier. CONSTITUTION: The first 90-degree hybrid coupler divides two input carrier waves into a liner path and a non-liner path. A variable phase converter receives the divided carrier wave at the linear path and compensates a phase error caused at the non-linear path. A variable attenuator receives an output signal of the variable phase converter and adjusts an amplitude difference for removing a main signal. A fixing attenuator receives the divided carrier wave at the non-linear path and adjusts inter-modulation generated in a mixer. A delay line compensates a delay time caused at the linear path.