Microstrip DGS Low-pass Filter

Model

The microstrip low-pass filter in this example is a planar filter which employs three DGS unit structures. It is a three-pole low-pass filter. An edge source is used to feed the microstrip line.

Simulation

The maximum grid step was limited to 3mm at the center of the frequency region of interest. The minimum grid step was 0.05mm. The grid is refined in the areas around the small gap regions to increase the accuracy. The UPML absorbing boundary conditions are used to truncate the domain.

Results

The simulation results show three-pole low-pass filter characteristics as expected. Electric and Magnetic fields on the surface of the filter structure are also recorded.