Broadband Doherty Power Amplifier Design

With the rapid development of novel generation wireless communications(LTE: long termevolution), high data rate and multi-mode transmitting impose demanding requirements andeffect for wireless communication system, which often employs much complicated non-instantenvelop modulation, there is no doubt that it renders high requirement for radio frequencypower amplifier. Additionally, green communication also urges people to concern theimprovement of power amplifier in efficiency; therefore it needs people to researchefficiency-enhancement technologies.The paper mainly addresses broadband asymmetrical Doherty power amplifier, itsdrainage efficiency is beyond30%with9.0dB backoff of output power and ACPR below-28.9dBc, good performance has been achieved, compared with its count parts.First the dissertation focuses the introduction of the history of wireless communication,the evolution of power amplifier system and power devices, then mainly involves non-linearcircuit analysis and simply analyzes its fundamental property, the following introduces thelinearization technologies of power amplifier, including LINC(linear amplification usingnon-linear component), feed-forward linearization technologies, pre-distortiontechnologies(analogy pre-distortion and digital pre-distortion); It mainly presented someefficiency-enhancement technologies, Classic Doherty power amplifier technology, EER(Envelop elimination and restoration) technology, ET (envelop tracking) technology, andswitch-mode technologies, class-F and inverse-F power amplifier are all included. the lastbut second mainly addresses the main job of the desertion on the simulation, design and poweramplifier product test, and non-balanced Doherty power amplifier theory analysis andsummaries are presented as well. Finally, the summary is given on this topic.