双频激励耦合PDE-AE射频系统的准周期稳态响应模拟算法研究

Quasi-Periodic Steady State Analysis of Coupled PDE-AE System in RF Circuits Driven by Two-Tone Signals

本文结合谐波平衡思想 ,提出在空间上离散MOSFET偏微分方程 ,建立与之相应的混合型多变量谐波平衡方程 ,扩展了谐波平衡方程的应用范围 .为了有效地完成这种复杂混合型多变量谐波平衡方程的求解 ,运用谐波平衡方程的同解变换、初始值预估以及阻尼Newton迭代算法等策略 ,使算法的收敛速度和计算性能都有大幅度提高 .以单平衡混频器为例的模拟结果进一步显示该方法不但能有效地反映出射频电路MOSFET器件的分布特性 ,且算法计算性能对频差变化不灵敏 。

Deriving from the thought of harmonic balance (HB), this paper presents hybrid multi-variables HB equations with space discretization of MOSFET PDE to extend the application of HB method. To solve the hybrid HB equations efficiently, an equations-scaling method of HB equations, initial values prediction, and dumped-Newton method have been proposed. They improve the performance of computation and convergence. New method is demonstrated on the example of a practical single-balanced mixer. Simulation results reveal the distribution characters of MOSFET explicitly, and algorithm works efficiently in widely separated two-tone exciting case.