UHF波段多载波高功率线性放大器研究

【作者】 查文杰；

【导师】 羊恺；

【作者基本信息】 电子科技大学 ， 电路与系统， 2007， 硕士

【摘要】 无线通信正是现今热门的重点科技领域，无论在个人手机或基站通信系统方面，前端的射频电路模块扮演相当重要的角色，而功率放大器更是射频模块中的关键组件，功率放大器的线性度、输出功率以及效率很大程度上影响着无线系统中的信号品质及通信距离。高功率放大器的线性度与效率向来是一对矛盾的指标，本设计采用自适应预失真前馈线性化系统来改善高功率放大器的线性度，在效率上也比一般的前馈功放有所提高。由于加入自适应控制模块，射频电路不受温度、时漂的影响，可始终处于较佳工作状态，这使得整个放大系统更为实用，也更具有拓展价值，可为民用或军用通信系统提供稳定而高效率的射频功率输出。经双音测试证明，本系统在输出总功率为48.6dBm时，三阶互调产物抑制比为60dBc，较未加入线性化系统前改善了30dB，此时系统总效率为11.9％。本系统采用先进数字控制系统，将自适应控制与射频线性化系统有机地结合为一个整体，同时应用了前馈与预失真技术，得到高线性的功率输出能力。更多还原

【Abstract】 The wireless communication is hot scitifical topic now. The RF circuit module play a very important role in both personal mobile phone and base station communication system.And the power amplifier is the key unit in the RF module. The linearity,efficiency and power of the PA affect the quanlity of signal and distance of communication strongly in the communication system.The efficiency and linearity of HPA used to be self-contradiction. In this paper, we considered both efficiency and linearization, and take the scheme of self-reaction control module plus predistortion and feed-forward technologies to improve the high power amplifier’s linearity. The efficiency is improved on the base of other feedforward PA. Because of the self-control system, the linearization power amplifier system can work steadily in defiance of the changing of temperature and time. It makes the system more practicably and expends the use of the linearization system,could afford high quanlity and efficiency power output for both common communication system and military system.Results are given for a series of two-tones inter-modulation distortion measurements and the IM3 is 60dBc. It is shown that a 30dB improvement in the inter-modulation margin can be achieved when the amplifier’s output is 48.6dBm. And the efficiency of the whole system is 11.9%.The system use the advanced digital control panal,combine the PA and the control system into an orgamic intergrality. It can get high linear power ouput siganl by the way of feedforward and predistortion.更多还原