在微波功率器件中,晶体管微波大信号的研究,一直是人们关注的问题。本文就对GaAsHEMT大信号进行研究。首先建立了GaAsHEMT的大信号等效电路模型,对其中最重要的非线性元件Ids、Cgs、Cgd建立了理论模型,进行了模拟结果与实验数据的比较,得到了较为满意的结果。最后根据提取出的参数,建立一种新的参数模型。该方法对设计MMIC有着很好的参考价值。 In microwave power devices, large-scale transistor microwave signal research, has been a matter of concern. In this paper, we study GaAsHEMT large signal. Firstly, a large-signal equivalent circuit model of GaAsHEMT was established, and the theoretical models of Ids, Cgs and Cgd, the most important non-linear components, were established. The simulation results and experimental data were compared and the satisfactory results were obtained. Finally, based on the extracted parameters, a new parameter model is established. This method has very good reference value to design MMIC.