Efficient analysis of resonant cavities by finite element method in the time domain

A numerical method is presented, based on finite elements in the time domain associated with spectral analysis techniques for resonant cavity analysis. The method uses edge elements on tetrahedra for the electric field interpolation. Time derivatives are discretised by the Newmark method, which allows an unconditionally stable scheme with second-order accuracy to be obtained. Standard discrete signal-processing techniques are used to improve the results and reduce the memory requirement. An extensive set of numerical results is included