基于自主研发的RF LDMOS功率晶体管以及散热法兰, 设计了一款用于无线通讯以及L波段和S波段雷达系统的大功率高效率的功率放大器。在保证了器件的射频接地以及散热的前提下, 在封装内部设计了输入内匹配和输出内匹配电路, 提高了管芯的阻抗点以便于电路板匹配。利用Doherty功率放大器结构可以提高功率回退处效率的特点, 结合输出内匹配对负载阻抗点的翻转作用, 得到了一种结构优化的Doherty实现方案, 在峰值功率处达到398 W的输出功率, 52%的漏极效率; 以及功率8 dB回退的平均功率处126 W的输出功率, 43%的漏极效率。这种改进技术进一步提高了功率回退处的效率, 相对普通Doherty功率放大器结构, 性能提升了16%, 改善了无线通信系统的射频性能。

Based on the RF LDMOS transistor and flange from the independent research, a power amplifier was developed for wireless communication as well as L band and S band radar system with high power and efficiency. On the basis of electric grounding and heat sinking, the input and output internal matching circuits were designed to increase the impedance of the transistor. Using the characteristics of the Doherty power amplifier for the backed off efficiency enhancement and internal matching for the invertion of impedance, a power amplifier with the performance of 398 W, 52% at peaking point and 126 W, 43% at 8 dB backed-off power average point was achieved. The optimized technique enhances the backoff efficiency of Doherty power amplifier, 16% relative increasment to common structure, and improves the radio frequency performance of the wireless communication system further.