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Transmittance in waveguide (Reflections on the input port).
Posted 26.10.2022, 07:47 GMT-4 Wave Optics Version 6.0 0 Replies
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I calculate the transmittance in waveguide in air. And there is a reflections on the input port. But I have only real part of refractive indexes. Most likely it is coupled with PEC boundaries. Because when I had tried to increase air domain the reflections decreased. Maybe I can increase air domain greatly and I will get T = 100 %, but it will be very big mesh. I tried to set a PML. But it was worse than PEC case. In fact, reflections are from impedance inconsistencies. But how can I correct it? And I increased mesh. It didn't help. For example, model with PEC (see picture).
Moreover, I tried to simulate with all covered PML area (including ports' sides). But I can't start simulation cause ports don't work when it's not extreme boundary of the model.
I have got near to 100% transmition in strip Si waveguide in air but only at 1 frequency. Of course transmission must not depends on frequency in this case (only real refractive index).
Please, help me. I can't solve this problem quite long time.
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Hello Nikita Yukhtanov
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