A new modified broadband asymmetric Doherty power amplifier

A new design using a single peaking power amplifier to modify multi-way peaking power amplifiers to realize multi-way asymmetric Doherty structure is presented in this paper. Compared with three-way Doherty power amplifier(DPA), the proposed asymmetric DPA shows higher efficiency at output power back-off range in a wide frequency band. The measured drain efficiency of 55 ∼ 66% over 700 MHz at 6–8 dB output power back-off and 35 ∼ 45 % at 10dB output power back-off(OBO) are achieved. Continuous wave(CW) signal measurement at 2.4 GHz exhibits a drain efficiency of 55% at 6dB OBO, 50% at 8 dB OBO and 41 % at 10dB OBO, respectively. It indicate a nice performance of the broadband DPA in large back-off range.