Study And Implemention Of Bandwidth Expansion For Class F Power Amplifier

Class F power amplifier is efficient to enhance the efficiency of amplifier by suppressing the harmonic components in output power, which was first studied in1992. And in recent years, it is still a hot topic due to its100%theoretical efficiency and its simple structure. Therefore, it is very significant to develop this technology to broader fields such as dual-band or multi-band applications to satisfy the requirements of modern communication standards.This thesis is aimed at realizing a concurrent dual-band Class F/inverse Class F power amplifier, and the major contribution includes:1) Explore the design methodology of dual-band Class F power amplifiers, analyze the key points and difficulties of concurrent dual-band power amplifier, summarize that the harmonic and intermodulation components are the influence factors to the concurrent performances, and also propose a solution to the problem.2) Present a novel graphic method to design the dual-band matching circuits by use of the Smith chart, which is more simple and convenient than traditional method.3) Design and implement a concurrent dual-band Class F/inverse Class F power amplifier operating at1.85GHz and2.65GHz.The measured peak output power achieve40.6dBm and40.8dBm with drain efficiencies of77.4%and75.4%and gain of14.9dB and14.5dB, respectively. When applied by concurrent continuous waves, the peak output power is39.9dBm and the efficiency is59.7%. Meanwhile, the adjacent channel power ratio is lower than-45dBc using20MHz16QAM signal.The proposed concurrent dual-band Class F/inverse Class F power amplifier is proved to be well-performed and have promising application prospects. To be specific, the discussion of concurrent dual-band power amplifiers and graphic method for dual-band impedance transformers are beneficial and conductive for the later dual-band power amplifiers’ design.