Researches On Simulation Technology For Microwave Nonlinear Scattering Function

Under large signal conditions, microwave power components usually work in the nonlinear domain. The classic s-parameter theory no longer fits for describing the strong nonlinear characteristic of the components accurately. Based on the research of the nonlinear theory, we put forward a new theory: nonlinear scattering function. Based on this theory, nonlinear scattering function matrix and nonlinear scattering function are defined. This theory extends the theory of s-parameter. It can describe the strong nonlinear characteristic of the components accurately. The theory of nonlinear scattering function extends the theory of the large signal nonlinear modeling. It is a black-box modeling method based on frequency domain measurement.In this article, the technologies of nonlinear scattering function modeling, simulation and CAD are fully researched for microwave power components. We start with the traditional modeling methods for diodes and FETs. The small signal model and the large signal model for microwave power components are extracted. Then harmonic balance method is used to analyzing the nonlinear characteristic of the component model. In this process, a new idea about transform matrix is presented, and the new technology of entire frequency domain analysis is used. The first time we have creatively put forward a method of nonlinear scattering function modeling based on harmonic balance analysis. And a nonlinear scattering function model for microwave power components is extracted. The nonlinear scattering function simulation technologies and CAD Technology are studied. The simulation results identified the nature of nonlinear scattering function from the perspective of qualitative and quantitative. Finally, the microwave nonlinear circuits are designed.Corresponding programs used in Matlab are compiled, which are capable of large signal modeling, harmonic balance analysis, nonlinear scattering function modeling, simulation and CAD. The programs include the entire process from analysis to modeling, simulation, circuit design. The result indicates that the programs have the advantages of high efficiency and strong practicability.