A Nodal Discontinuous Galerkin Time-Domain Method Based on Wave Equation

This letter develops a nodal discontinuous Galerkin time-domain method based on wave equation (NDGTD-WE) to accurately solve the electromagnetic problems. The governing equation of the NDGTD-WE method has been formulated by using interior penalty numerical flux and the nodal basis functions have been used to expand the unknown electric field. In order to reduce the memory usage of the NDGTD-WE method, a low storage scheme has been developed by transforming the integral in the global element to that in the reference element and meanwhile calculating the nodal bases in the global element in terms of the modal bases in the reference element. The wave sources of the NDGTD-WE method in free space and waveguide have been derived. Numerical examples show good performance of the proposed NDGTD-WE including low memory and good accuracy.