Coaxial to Waveguide Coupling
Feeding a waveguide from a coaxial cable is a straightforward way to achieve electromagnetic waves inside a waveguide. Due to its small size and circular shape, the cable contributes significantly to the overall size of the problem. It is therefore necessary to keep the cable as short as possible.The coaxial feed must be modeled with enough length, so reflected waves are either damped out in the cable (evanescent modes) or turn into propagating modes. Propagating modes are efficiently terminated with a matched absorbing boundary condition, called the Port boundary condition in the RF Module.
This model shows how to use assembly pairs and the Port boundary conditions to feed a rectangular waveguide. The port condition can be placed directly at the surface where the cable enters the waveguide, and only a short cable part, modeled as a perfectly matched layer (PML), is subsequently necessary.
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The deformed slice plot shows the z component of the electric field, while the boundary plot on the cable and walls is the normalized surface current density. |
Engineering Fields
- RF & Microwave Applications
- Photonics & Optics
Application Areas
- RF Systems