Transistor and Power Amplifier Characterization to Maximize Simultaneous Linearity, Efficiency, and Power

Power Amplifiers (PAs) are a significant contributor to the overall power efficiency and linearity of a RF wireless transmitter. Modern wide-band communications standards and the desire to maximize channel capacity result in signals with large instantaneous signal bandwidth and peak-to-average ratio (PAR). These signals are difficult to amplify efficiently with good linearity. In this presentation we discuss methods to characterize transistors under modulated conditions using passive loadpull. The effects of baseband impedance, thermal and charge trapping and harmonic terminations are investigated. Finally, we present a thorough analysis of a hybrid GaN PA performance under concurrent signal excitation.