TY - JOUR ID - 3447 TI - Analysis of Parametric Oscillations in High Power Amplifiers JO - Scientia Iranica JA - SCI LA - en SN - 1026-3098 AU - Nikandish, G. AU - Yousefi, A. AU - Mohammadi, E. AU - Babakrpour, E. AU - Medi, A. AD - Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran Y1 - 2013 PY - 2013 VL - 20 IS - 6 SP - 2084 EP - 2092 KW - Large-signal instability KW - parametric oscillation KW - pHEMT KW - power amplifiers KW - Stability analysis DO - N2 - 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. UR - https://scientiairanica.sharif.edu/article_3447.html L1 - https://scientiairanica.sharif.edu/article_3447_11c00ed1095b92822310b8c6b91e5806.pdf ER -