When it comes to highly resonant structures, such as bandpass filters and diplexers, the Frequency Domain solver provides great benefits in terms of the simulation accuracy versus speed. Furthermore, it features unique technologies such as the moving mesh, which is important for the mitigation of numerical noise generated by changes in the discretization. It also offers a model order reduction method that is very fast, even in calculating broadband results.
The Time Domain solver is the perfect solution for broadband traveling-wave components like transmission lines and transitions, as well as highpass/lowpass filters.