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How to model a line current with good absorption by PML
Posted 27 mag 2015, 03:07 GMT-4 RF & Microwave Engineering Version 4.4 0 Replies
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I want to model the electric field generated by a swift electron beam. Considering a 2D situation, the electron density of the beam is rho(x,y,t)=delta(v*t-x)*delta(y). So the electron beam is along the x-axis with a velocity v. Under the Fourier transform, we can get the density used for the simulation the Fourier component of the field in the frequency domain. The density is rho(x,y,omega)=delta(y)*exp(-i*omega*x/v). So the electron beam can be modeled as a line current with a phase velocity omega/v now.
I model the line current in for 2D using the expression above and get the confined electromagnetic field around the beam. However, what troubles me is the absorption of the field near the PML boundary. I don't want any scattering or reflection at the boundary and I don't want use the periodic boundary condition. The PML seems not work well for the line current and the field near the boundary do not converge, as seen in the attachment.
Even I used the port boundary condition with field distribution exactly accord with the field of the line current, the field is still not absorbed. Can anyone show how to resolve this problem?
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Hello Pan Deng
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