LDMOS宽带功率放大器匹配电路设计

Design of LDMOS Broad Band Power Transistor Amplifier's Match Circuit

针对LDMOS宽带功率放大器匹配电路设计,提出了一种快速、有效的方法。采用多节并联导纳匹配法得出宽带匹配电路的初始值后,利用ADS软件对匹配网络的S参数进行优化。仿真结果为:在频率范围为1.3 GHz～2.3 GHz内,两端口的反射系数均小于-25 dB,匹配网路的传输系数接近0 dB。为实现更好的阻抗匹配,再用ADS优化匹配网络,使其阻抗值更接近功率晶体管的实际输出阻抗值。此方法对快速有效地设计宽带功率放大器匹配电路有着很好的借鉴作用。

In terms of the LDMOS broad band power amplifier matching circuit＇s design,a sort of fast and effective method was proposed.After adopting the multi parallel admittances matching to obtain the broad band matching circuit＇s initialization,ADS software was used based on the method of moment to optimize matching circuit＇s S parameter.The simulation results showed that port＇s reflectance is smaller than-25 dB between 1.3 GHz and 2.3 GHz,transmission factor of the matching network approaches 0 dB.In order to make impedance matching well,ADS software was used to optimize the matching network again,which makes its impedance approach power transistor＇s actual output impedance.The method is worthy of learning for designing broad band power amplifier matching circuit fast and accurately.