A Digital Amplitude-to-phase Conversion for High Efficiency Linear Outphase Power Amplifiers

This paper introduces a digital amplitude-to-phase conversion scheme to facilitate the outphase amplifying concept, enabling the use of high efficiency, non-linear power amplifiers in linear systems. The digital implementation enables a fast and accurate amplitude-to-phase conversion by exploiting the computational capability that can be easily incorporated in today´s integrated circuits (ICs). The proposed scheme minimizes amplitude variation of the outphase signals, which reduces the gain requirement of the power amplifiers that can be traded for higher efficiency. Our analysis demonstrates that outphase amplifying can be twice as efficient as the conventional class-A power amplifiers, and is suitable for wireless systems with large peak-to-average ratios