R320 Open-Ended Hollow Rectangular Waveguide

1. Example description

In the following example an open-ended hollow rectangular waveguide is simulated, see Fig. 1. The cross section of dimensions 7.112 mm and 3.556 mm. One end of the waveguide is left opened Fig.1. Since the characteristic wave impendence of the waveguide is near to the free space impendence, we expect radiation from the opened end.

Fig. 1: Layout of the rectangular waveguide.

2. TLM model

The waveguiding structure, excitation-type and simulation setup are given in the TLM model files and I3D.r320_open.

In the first file the structure is excited with a Gaussian signal. The excitation is modelled by a vertically polarized electric field at one port of the waveguide as shown in Fig. 1. Absorbing boundary conditions are used at the boundaries of the simulation domain.

3. Simulation Results

3.1 Electromagnetic Field Visualization

As simulation results we display a snapshot of the field distribution, Fig. 2, and a snapshot of power flow distribution, Fig. 3. Both inside and outside the waveguide.

Fig. 2: The electromagnetic field distribution inside the waveguide and in the air.

Fig. 2: An other snapshot of the electric field distribution inside the waveguide and in the air..

Fig. 3: Volumetric visualization of the electric field intensity.

Fig. 3: A snapshot of the absolute value of the Poynting vector |P|.