250MHz固态功率放大器的设计

Design of a 250-MHz solid-state power amplifier

固态功率源代替真空管功率源设备是目前射频功率源系统的发展趋势。本文介绍了一台工作在250 MHz的固态功率放大器模块的设计过程。放大器模块使用荷兰恩智浦半导体公司生产的BLF578XR型号晶体管,并且采用传输线匹配和集总元件匹配相结合的方式进行设计。通过理论计算得到匹配网络的初始值,并利用ADS(Advanced Design System)软件对匹配电路进行仿真和优化。测试结果表明,该功率放大器模块输出功率达到了850 W,功率增益达到了26 d B,功率附加效率达到60%。结果表明,该设计完全达到了系统设计要求的性能指标,并具有较强的实用性。

Background The development trend of radio frequency power source systems is to replace vacuumpower source devices with solid-state power amplifiers. Purpose： This paper introduces the design process of asolid-state power amplifier operating at a frequency of 250 MHz. Methods： A BLF578XR transistor manufactured byNXP semiconductor has been used in the amplifier model. The design of matching network adopts the method ofcombining transmission lines and lumped elements. The initial value in matching network was achieved throughtheoretical calculation, then simulated and optimized by the software ADS （Advanced Design System）. Results： Theresults of measurement showed that the output power of power amplifier module was over 850 W, power gain wasover 26 dB, and power added efficiency was over 60%. Conclusion： The designed parameters were all achieved inthe power amplifier module, which can be fiu＇ther applied in scientific use.