a question of gaussian pulse in cst

i want to simlute by a gaussian pulse.
the definiton of gaussian pulse is Exp(-j*(t/σ)2).
but i don't find this function in excitation signal.
I want to know how definite the gaussian pulse in cst?
The definition of gaussian pulse is about the time,but in cst ,the parametre
of gaussian pulse is about frequency. Why?
Thanku

ChowChen shalom,
HFSS v10 has a guassian wave excitation.
Regards,
Itai

Is it time domain?

No, HFSS is frequency domain.
In CST the gaussian pulse is determined by the frequency range in order that the time domain response contains all the frequencies of interest.
if you want to explicitly use a time domain pulse then you can use the 'user defined' waveform, and put in a VB equation where it shows you.