Efficient Threshold Evaluation for High-Power Microwave Breakdown with the Discontinuous Galerkin Spectral-Element Time-Domain Method

As the miniaturization and power of microwave devices increases, there is a growing risk of high-power microwave (HPM) breakdown, severely impacting the reliable performance of the system. Therefore, in order to better evaluate the breakdown properties of such microwave devices, an efficient and accurate numerical method are presented in this article. An eigenvalue equation based on the physical model is first established and is discretized with the spectral-element time-domain (SETD) method to accurately calculate the breakdown threshold. In addition, the discontinuous Galerkin (DG) technique with a nonconforming mesh is employed to improve efficiency for complex microwave structures. This approach significantly reduces the number of elements, especially for multiscale complex structures, thereby saving computational resources. Several numerical simulations validate the accuracy and efficiency of the proposed method, compared with commercial software and experimental results. Overall, we believe that the proposed method provides an effective tool for evaluating the capacity of HPM devices.