Sharif University of Technology Scientia Iranica 1026-3098 20 6 2013 12 01 Analysis of Parametric Oscillations in High Power Amplifiers Analysis of Parametric Oscillations in High Power Amplifiers 2084 2092 3447 EN G. Nikandish Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran A. Yousefi Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran E. Mohammadi Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran E. Babakrpour Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran A. Medi Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran Journal Article 2013 08 04 A large-signal analysis of sub-harmonic parametric oscillations in power amplifiers (PAs) is presented in this paper. Simplified models for current-voltage and channel charge characteristics of short-channel pseudomorphic high electron mobility transistors (pHEMTs) are adopted to investigate the effects of the device transconductance and gate-source capacitance nonlinearities on the amplifier stability. A 5-W Ku-band PA is designed to demonstrate application of the presented analysis. The MMIC PA is implemented in a 0.25-μm GaAs pHEMT process. Measurement results indicate that the PA features 37.5 dBm (5.6 W) average output power, 36% power added efficiency (PAE), and 18 dB average small signal gain. https://scientiairanica.sharif.edu/article_3447_11c00ed1095b92822310b8c6b91e5806.pdf