Efficient Electro-Thermal Analysis of SIW Filters Considering Temperature-Dependent Characteristics of Materials

In this article, an efficient method for electro-thermal analysis of substrate integrated waveguide (SIW) filters is proposed. First, an analytical model of electromagnetic (EM) losses for the SIW filters is developed to obtain the heat source. Subsequently, the electro-thermal analysis is performed with the in-house developed solver based on the finite difference method (FDM), where the equivalent thermal model of via arrays is introduced to improve the computational efficiency. To ensure accuracy, the temperature-dependent (TD) material properties of both the conductor and dielectric are considered. Moreover, Aitken's dynamic relaxation method is used to accelerate the convergence of the electro-thermal simulation. Finally, the accuracy and efficiency of the proposed method are validated through several typical examples. The results obtained by our method exhibit good agreement with the simulation conducted by the commercial multiphysics solver.