Research And Design Of Reconfigurable And Continuous Power Amplifier

The design of multi-mode/multi-banded RF systems has recently become a hot research area due to the rising demand for wireless communication technologies and the tightening of spectrum resources.There are three primary categories of multi-mode/multiband power amplifiers: concurrent multi-band amplifiers,reconfigurable amplifiers,and ultra-wideband amplifiers.Based on the design theory of class-F amplifiers,this study investigates and constructs ultra-wideband amplifiers and reconfigurable amplifiers by combining a filtering network and a matching network,with the following specific work:1.A continuous class-F amplifier across three octaves is designed.Firstly,a symmetrically structured quasi-elliptic low-pass filter network is designed,which generated two different transmission zeros at finite frequencies by introducing a series resonant circuit into the network.This enabled the filter to have sharp roll-off characteristics and a relatively wide stopband.The insertion loss of the filter was less than 0.09 dB in the low-pass broadband of 2.4 GHz.Based on the symmetrically structured quasi-elliptic low-pass filter network,an output matching network is designed,which could enable the impedance curves of the fundamental wave and the second and third harmonics to fall completely within the high-efficiency region obtained by load pull.Test results show that when the input power is 29 dBm,the amplifier has a PAE greater than 60% and a gain greater than10 dB across a wide frequency range of 0.3-2.4 GHz,with an output power exceeding 39 dBm.Additionally,the frequency selectivity of the power amplifier is good.2.A continuous Class-F amplifier with reconfigurable frequency and bandwidth is designed.By utilizing the tunable capacitance characteristics of varactors,a reconfigurable band-pass network was obtained by cascading a symmetrical quasi-elliptic lowpass filter network and a generalized Chebyshev high-pass network.The passband of the band-pass filter can be adjusted by tuning the capacitance value of varactors.Based on this reconfigurable band-pass filter network,a dynamic impedance matching network is designed that realizes the dynamic impedance matching between the output terminal of the transistor and the reconfigurable band-pass filter network.Test results show that when the input power is 29 dBm,the power amplifier can achieve center frequency reconfigurability in the frequency range of 0.95-1.9GHz,with a fixed bandwidth of 400 MHz.In addition,it can achieve bandwidth reconfigurability in the frequency range of 1.1-1.8GHz,with a fixed center frequency of 1.45 GHz.The drain efficiency is greater than 60% and the gain exceeds 10 dB in all reconfigurable frequency bands,with an output power exceeding39 dBm.