Design of 200 W wideband Doherty amplifier with 34 % bandwidth

This paper presents the design and implementation of a 200 W wideband harmonically-tuned Doherty amplifier. The power amplifier (PA) is targeted for wide range base stations operating within the frequency range 1.7-2.3 GHz. Proper and explicit design approach of the main output matching network was followed taking into consideration the frequency and power dependency of the load impedances introduced at the input and output ports of the matching network. The PA had an output power in the range of 153-205W, measured over 1.6-2.25 GHz (34% bandwidth). At 6 dB output power back-off, the PA had a minimum power-added efficiency (PAE) of 40%. Using digital pre-distortion (DPD) linearization for an LTE signal at 1.85 GHz, the PA had adjacent-channel leakage ratio (ACLR) of -40 dBc, measured at 28 W of average output power with average drain efficiency of 50%.