dipole source

As the title...


How to implement the electric dipole source in FDTD?

Any one can provide examples for me or some advices?

Thx alot~

This may be the simplest of all sources to implement and there are two ways you can do it: hard soure and soft source. The "best" way for you is probably the soft source as this is closer to the physical situation.

1. Pick a point to implement the dipole source (nx,ny,nz)

2. Inside your main FDTD loop, you will have a statement like:

Ez(nx,ny,nz) = s(nt); %% hard source
Ez(nx,ny,nz) = Ex(nx,ny,nz) + s(nt); %% soft source

where (nx,ny,nz) is the position of the source, Ez is the z-component of the electric field, nt is the integer time step, and s(t) is the source as a function of time and probably a short gaussian. You can, of course, use Ex or Ey as the dipole polarization as well.

Hope this helps!

-tip

hi,

is the dipole source same as the pointwise source?

What do u mean by "pointwise source"?

yes (provide you mean point sources).

Dipole source describes what you model, point source how you implement it.

dipole source ~= point source, I wonder