# How to normalized electric field in case of dipole source near to adjacent to the metal surface.

Member Posts: 1
edited May 26

I am simulating a CAD which has a dipole source near a metallic object. And I am calculating the electric field away from that metallic object. For unit electric field amplitude, the actual power fed into simulation for a dipole source near a metallic object is greater than power fed into simulation for a dipole source in a homogenous medium. While calculating the electric field using field profile monitors, the electric field is normalized by considering dipole in a homogenous medium. I would like to calculate the electric field which is normalized to the fields corresponding to the actual power that enters into the simulation region. Could you please help me with this?

Tagged:

• Hello Nitingupta,

The script command dipolepower returns the actual power radiated by the dipole in an inhomogeneous environment. Simply divide by the purcell factor = source_power/dipole_power to get the power normalized to the actual injected power. More is information is available here.

This doesn't apply to the electric field though. It is not entirely clear how you would like the fields normalized in the frequency domain, so I would refer you to these pages for more information. Perhaps you could divide by the amplitude of the injected fields?

Best,

• Thank you for your quick reply. I have seen those links earlier, but I could not figure out the solution to my problem. I would like to further clarify my problem to you.

So I am using a field profile monitor. Under CWNORM, the electric field data obtained from the field profile monitor is normalized to the incident amplitude of the electric field of the dipole source. My aim is to calculate the electric field enhancement at a point which is the ratio of the simulated electric field amplitude at that point to the "incident electric field". As the power is related to the amplitude of the electric field, according to the formula[P = 1/2 ∫ Re(ExH*) dS, the different power of a dipole in an inhomogeneous medium can be considered as the power emitted by a source having an effective electric field amplitude. For my simulation, I want to divide the simulated electric field by an "incident electric field" which is the electric field corresponding to the Dipole power and not the Source power.

How it can be done in the frequency domain, I could not figure out. Let me know if this can be done some other way.

Thanks and regards,

Nitin

• Hello Nitin,

This will be a linear system, so you can use cwnorm. I think you can then just renormalize the power with dipolepower or equivalently purcell factor.

The script command dipolepower returns the actual power radiated by the dipole in an inhomogeneous environment. Simply divide by the purcell factor = source_power/dipole_power to get the power normalized to the actual injected power.

Best Regards,