HFSS Driven Terminal, Excitation in terms of Voltage

Hello,

I am using Driven Terminal for my simulation with some 50Ohm CPW waveguide.
On getting the results, I want to simulate for the given power in dBm, how much current I will end up running through some sections.

However in Driven Terminal the excitation is in terms of incident voltage.
May I know if I should take this voltage as Vpp, Vrms, or Vpeak?

For example, I know the power running through the line would be ~-40dBm, from this website I see the conversion:
http://ifmaxp1.ifm.uni-hamburg.de/DBM.shtml

[dBm] [Watts] [Volts]rms [Volts]p [Volts]pp
-40 0.100E-06 2.236 mV 3.162 mV 6.324 mV

May I know which number I should set for the incident voltage?
Many thanks.

I believe it's peak voltage. You should be able to verify by observing the resulting field levels.