Research And Design Of 5G RF Front End Power Amplifier

With rapid development of information technology,mobile communication systems have developed into the fifth generation,referred to as 5G.Design of MMIC in 5G RF Front-End has been one of research hotspots of microwave technology in recent years,and it has been also one of hot areas of domestic substitution.In this thesis,a MMIC power amplifier for 5G RF front-end module has been designed after studying and researching 5G RF front-end integrated circuit.The main work done is as follows:（1）A linear bias circuit with voltage compensation and temperature compensation is proposed to improve the linearity of power amplifiers,by analyzing the heterojunction bipolar transistor（HBT）.If the input signal power received by HBT increases,the base-collector voltage V_BE of HBT will decrease,and the linear bias circuit plays a role in maintaining the base emitter voltage V_BE of HBT,which is voltage compensation.If the temperature of HBT increases,the direct current of HBT in the transistor will sharply increase,and the linear bias circuit maintains the current flowing through HBT,which is temperature compensation.（2）A high output and high linearity MMIC power amplifier for n78 band（3.3G-3.6GHz）is designed by analyzing requirements of 5G RF front-end integrated circuits.This power amplifier uses the linearization bias circuit described above to improve the linearity of this MMIC power amplifier.The second harmonic suppression network is designed to suppress effect of second harmonic waves.ESD circuits are designed to protect this chip.Then,schematic simulation,electromagnetic field simulation and layout-principle co-simulation of this power amplifier are all completed.Voltage compensation and current compensation effectively improve the linearity of the power amplifier.（3）This power amplifier has been taped out and tested.Test shows that the gain 1d B compression point output power(P_{1d B})of this power amplifier is 31 d Bm,and saturated output power reaches 32 d Bm.When the output power is 28 d Bm,the second harmonic power is less than-40 d Bc,and ACPR is about-35 d Bc.This power amplifier works well.