Some of the most common instability phenomena in power amplifiers (PAs) are explained. PAs are used in wireless communications, radar, RF heating and imaging. Recently developed stability-analysis tools can be used for understanding the desired behavior, which can be efficiently predicted and corrected at the simulation stage. The techniques, based on harmonic balance, have been illustrated by means of their application to Class E/F amplifiers at 29 MHz, which exhibited self-oscillation, hysteresis, and chaos. A simplified equivalent circuit at the oscillation frequency has been derived, enabling an efficient determination of the topology and location of the required stabilization network. The circuit has been globally stabilized for all the expected values of drain-bias voltage and input power.
ASJC Scopus subject areas
- Physics and Astronomy(all)