| dc.description.abstract | With the current expansion of the wireless communication industry,system integration has become a major trend to meet hallenges.Microwave circuits are used within RF section of wireless communication system.The power amplifier is controlled by the size,cost,and performance of the RF section,hence the power amplifier plays an important role in the wireless communication system.
This thesis is major to design high efficiency and linearization MMIC (monolithic microwave integrated circuit)power amplifier.In the high efficiency MMIC power amplifier,the paper demonstrated the 1.8GHz class E power amplifier.In addition,it is shown to use active elements (InGaP/GaAs HBT)’s base-collect junction and combine a parallel capacitance to form active bias.Active bias replace resistance bias without power consumption.This design is 5.2GHz two stage power amplifier to improve the nonlinear factor of power amplifier—gain compression.Then using network analyzer (HP-8510C) and Maury ATN load-pull system to measure all microwave power amplifiers.The measurements include S parameter, power gain,output power,PAE,IM3,and ACPR and analyze the results further.
The measured result of 1.8 GHz power amplifier is as followed:(1) small signal S11 = -11.4 dB，S21 = 24.2 dB，S22 = -5.52 dB.(2) power gain= 24.2 dB,maximum output power=15.5 dBm,maximum PAE=39.4%,OIP3=22 dBm,ACPR=-30 dBc
The measured result of 5.2 GHz active bias power amplifier is compared to the resistance bias class A power amplifier.The result is improvement of gain compression of 2 dBm input and improvement of OIP3 of 0.8 dBm. | en_US |