Design of linearity-enhanced and high-efficiency Doherty power amplifier using a new phase compensation technique

This paper introduces a methodology to design linearity-enhanced and high-efficiency Doherty power amplifier (DPA). The proposed approach leverages the phase difference within the DPA's combiner at the power combining point to regulate both amplitude-to-amplitude (AM-AM) and amplitude-to-phase (AM-PM) distortion. It effectively mitigates the distortion generated by the transistor and enhances the linearity of the DPA. A DPA operating at 2.2-2.45 GHz provides output power of 45 dBm with 9 dB back-off and saturation drain efficiency over 49.2% and 72.1%. And the gain and phase distortion are controlled to 1.5 dB and 2.5 ∘ . Using the 10/20/40 MHz OFDM signal with a peak-to-average ratio (PAPR) of 9 dB, the average drain efficiency is approximately 45% at an average output power of 36 dBm. While the adjacent channel power ratio (ACPR) is below −36 dBc and the error vector magnitude (EVM) is below 2.6%, without any digital predistortion (DPD) technology.