Reference Vector
The reference vector specifies the reference direction for a waveguide port.
The reference vector is indicated by a white line connecting the edge of a waveguide with
the centre of the waveguide port and shows the direction of m, where m
corresponds to:
- the number of half-wavelengths across the width of the waveguide (rectangular waveguides).
- the number of radial variations (circular waveguides).
For a rectangular waveguide, defining the reference vector in one direction, the dominant mode at a frequency might be TE10. Rotating the reference vector with 90° and solving the same problem, the dominant mode will be indicated as TE01.
For a circular waveguide there is no ambiguity with regards to which direction is for m or n.
Note: Information given for the modes in the .out file corresponds to the specified direction of the reference
vector.
If the reference vectors differ between ports, it results in a phase mismatch between the
S21 and S11.