Microstrip Radial Stub - CST2013 MWS Examples

下载CST设计文件

General Description

A microstrip line with radial stub on a dieletric layer is considered.

This example demonstrates the transient calculation of the scattering parameters of a microstrip radial stub using a parameter sweep. The angle of the stub is varied from 30 to 90 degrees in a total of three steps.

Structure Generation

The background material is defined as vacuum, the units are changed to millimeters, gigahertz and nanoseconds, and the boundary conditions are set to "electric". Furthermore, the mesh settings are changed to account for the planar microstrip structure.

The substrate and the microstrip line are created as boxes in the corresponding layers. A flat, perfectly conducting cylinder is added, and the working coordinate system (WCS) is aligned to its center. The WCS is rotated twice and is used as a cutplane for slicing the flat cylinder, which thereafter becomes the radial stub. All shapes of the PEC layer are combined.

The upper distance to the boundary above the substrate is increased by approximately seven millimeters, and a magnetic symmetry condition is specified.

Solver Setup

The default settings for the transient solver are not altered. After the parameter sweep has been selected from the transient solver's dialog, a new sequence is added, and the parameter angle is chosen to be swept from 30 to 90 degrees in three steps.

All S-Parameter results are automatically stored for every parametric solver run. This storage can be controlled for all 1D signals by selecting Post Processing: Manage Results Parametric Properties .

Post Processing

After the parameter sweep has finished, the results can be found in the result tree (1D Results S-Parameters). It is observed that the resonant frequency shifts to the upper end of the frequency range as the angle of the stub increases.