RF high power Doherty amplifier for improving the efficiency of a Feedforward linear amplifier

This paper presents a RF high power Doherty amplifier for improving the efficiency of a 30 W Feedforward linear amplifier used in W-CDMA base-station applications. A Doherty amplifier using a single push-pull LDMOS FET is proposed as the main amplifier of the Feedforward linear amplifier. The peaking amplifier's compensation line and gate bias effects are analyzed, at a 6 dB backed off. From the experimental results, a 2.2% PAE improvement on the 30 W Doherty Feedforward linear amplifier is achieved in comparison to a conventional Feedforward linear amplifier.