I would like to extract the far-field analysis of an FDTD simulation with Bloch boundary conditions and a tilted source.
For that, I have set-up a 2D test simulation in free-space with a plane source (tilted by 10°) and a monitor (Bloch_and_far_field.fsp). After the computation, I plot the far field vs wavelength with the following code lines:
f=getdata("monitor","f"); w=c/getdata("monitor","f")*1e6; Ey_ff=transpose(farfield2d("monitor",1:length(f))); theta=farfieldangle("monitor"); image(w,theta,Ey_ff,"Wavelength (nm)","angle (deg)","|E|^2 far field");
The result is the following:
It is strange because I was expecting to have a straight line at 10° everywhere.
Could someone help me to figure out where is the problem?