基于场效应管阻抗参数测试的宽带功率放大器优化设计

Optimized Design of a Broadband Power Amplifier Based on Impedance Measurement of FET

摘要: 设计了一个工作在800～1250MHz的宽带线性高功率放大器.用负载牵引方法测试了LDMOS场效应管宽带内的大信号阻抗参数,利用测得的阻抗参数优化设计了功放的匹配电路.实测功放的1dB压缩点输出功率大于44.5dBm,二次谐波小于-25dBc,输出功率为38.5dBm时双音测试三阶交调(IM3)优于-44dBc.

Abstract: A broadband linear high power amplifier was designed,which operated through the band from 800MHz to 1250MHz.A simple load-pull method was used to acquire the input and output impedance parameters of the LDMOS FET in the band.Based on the impedance parameters,the matching networks of the amplifier were designed and optimized.Measured results give the P1dB output power over 44.5 dBm,the 2nd harmonic below-25dBc,and the IM3 better than-44dBc with 2-tone test at 38.5dBm output power.