Design and Performance Verification of S-Band High-Efficiency GaN Internal Matching Power Amplifier

An S-band CW internal matching power device with high efficiency and high reliability is developed. Continue with my self-developed 8mm chip, the optimal impedance of GaN device was extracted by load-pull and large signal modeling, the S-band GaN internal matching power amplifier has been successfully developed by using internal matching technology, which is integrated in the ceramic tube of QF136PC with the inner cavity size of 13.6mm×13.6mm. Finally, the operating bandwidth of 300MHz is realized. Under the operating of 28V and continuous wave conditions, the in-band output power is greater than 45.19dBm(33.05W), the power gain is greater than 13.19dB, the power additional efficiency is greater than 66.5%, and the drain efficiency is greater than 69%. At the same time, the performance of different voltages, different input power, breakdown voltage of the device, and heat distribution under DC and RF conditions were full evaluated. Through the junction temperature test, the highest junction temperature of the device is 127°C in the environment of 70 °C platform temperature, which meets the requirement of space class I derating.