针对电磁环境模拟器应用设计了一个全固态UHF波段多级宽带线性高功率放大器。驱动放大器工作在A类，末级放大器以三个AB类功放模块频域分段覆盖工作频段，通过控制PIN开关切换。末级输出接低通滤波器改善谐波。实测从400MHz～1250MHz，功放的1dB压缩点功率为25W（44dBm），二次谐波低于-40dBc，输出功率在38dBm时双音测试三阶交调（IM3）优于-44dBc。

A multi-stage UHF broadband linear high power amplifier(PA) is designed for the application as an electromagnetic environment simulator. The drive amplifier operates in class-A . The output amplifier is composed of three class-AB amplifiers which cover the whole band by segment and the segments can be switched by PIN switchs. The measured result shows the 1 dB compression point of the PA is about 44 dBm(25 W), the 2nd harmonic is below-40 dB and the 3rd order intermodulation distortion(IM3) is better than-44 dBc(2-tone test at 38 dBm output) in the whole band from 400 MHz to 1 250 MHz.

TN955