【摘要】 任何含有有源器件的微波放大电路在一定情况下都会表现出非线性特性,同时GaAsFET自身存在的内部反馈和电路元器件的电磁辐射可能会导致信号的正反馈,从而引起放大电路的灾变.本文采用GaAsFET的Curtice-3大信号模型,应用电路定律建立微波放大电路的状态方程,并在时域中用龙格-库塔法求解.最后编程模拟了正反馈情况下电路的灾变现象.更多还原

【Abstract】 Under certain circumstances, any microwave amplifier circuit including active components will express the nonlinear characteristic. If the inner feedback of GaAsFET or the electromagnetic radiation of the components in circuit leads to positive feedback of signal, the self-oscillation phenomenon will happen. Even the worse, the circuit failure may occur. Adopting the Curtice-3 large signal model of GaAs FET, the state equations of the circuit are built based on the Kirchhoff’s law, and calculated by the aid of R-K method. Finally, supposing that the positive feedback exists, the self-excitation and failure phenomenon of the circuit are simulated by programming.更多还原