Broadband Design and Verification Approaches of RF Power Amplifier for 5G Front-End Transmission

Abstract

The broadband digital telecommunication has been about to step up into next generation level after 4G, so called 5G. 5GNR (New Radio) deliversmuch higher throughput up 20Gbps with wider bandwidth, low latency, higher number of multi-channel resource basesand higher density multimedia information in new band: sub-6GHz and millimeter wave band. Wide bandwidth of 5G NR of 100MHz in sub-6GHz band to 1-2GHz in mmWave band requires high linearity RF Amplifier of the front-end module (FEM). FEM of 4G or 5G terminals should be capable of handling transmission rate over 100Mbps to 20Gbps with low BER, low EVM (error vector magnitude) and low non-linearity spectrum products. High density composite M-ary modulation and much higher number channel of resource base of 5G mode signal than those of 4G transmission moderequire stringentodd-order intermodulation suppression, low spurious response and low spectrum noisebesides low phase noise of the local oscillator.The requirement of wide bandwidth, high linearity and high spectrum quietude imposes particular design and implementation proceduresof the RF Amplifier of FEM employingRF/microwave transistor/s. Broadband design and simulation of RF Amplifier of the FEM should be performed, in sequentially: large signal modeling, load pullingoptimization, broadband impedance matching and broadband signal verification by mixed signal HB simulation and measurement. RF broadband performance were evaluated and verified from broadband S-parameter, gain-magnitude, vector modulation constellation, EVM, signalspectrum and bandwidth measurement. Analysis and verification on design of broadband RF Amplifier of FEM are obtained from the comparison simulation and measurement of the broadband RF Amplifier. The switched mode of class-E RF Amplifier for the FEM will also be evaluated.