Incident Power

Incident power for an antenna structure is defined as the time-averaged power incident on the port(s) of the antenna:

(1)

where

• P_inc is the incident power in watts.
• Re is the real part of a complex number.
• A is the union of all port boundaries in the model, including Wave and Lumped Ports, but excluding Floquet ports.
• E_inc is the incident electric field.
• H^*_inc is the conjugate of the incident magnetic field.
• dS is the local port-boundary unit normal directed into the 3D HFSS model.

In the Edit Sources window of a terminal project, you specify total voltage V instead of the modal incident power. Using the underlying modal S-matrix, HFSS converts the terminal excitation to total fields at the ports, and then applies the general definition. As a result of this procedure, the incident power in a terminal project depends on both the user-specified stimulation as well as the model itself.