Integration line and Terminal line in HFSS

hiall,
whats the use of integration line/terminal line. IF you wish u can leave it undefined. In this case how does the software calculate Z0(Characteristic imp). What modes it uses.

The mode is defined automatically, it just that sometimes the phase is not as we wanted. For example, think about a rectangular waveguide. If you don't define the integration line, sometimes electric field may polarize downwards (negative phase) instead of upwards.

hi,
Thanx for the clarification. So in some cases if we dont define terminal lines we may get results 180 deg out of phase ...rite?
thanx
cv

I think it is somewhat more complicated than a 180 phase differece. Consider, for example, the coplanar waveguide that support >1 propagating modes or degenerate modes...