I do not understand the behavior of the transmission parameter S21 in a rectangular wave guide excited with two Port, there are differences in behavior between S21 and dBS21, these are the following differences:
-S21 has peaks. Evident when exporting data and analyze it presents oscillation between 1 and -1
-dBS21 plot in COMSOL, the oscillatory beahavoir of S21 is not presente and what is more strange is when calculated
with the formula (dBS21 = 20 * log (abs (S21)), I get different values from those used in the graphic COMSOL dBS21 and the oscillatory beahavoir is present.
If Comsol used otherwise for caculation of dBS21 parameter please enlighten me, that the results did not close.
Please help me!
-S21 has peaks. Evident when exporting data and analyze it presents oscillation between 1 and -1
-dBS21 plot in COMSOL, the oscillatory beahavoir of S21 is not presente and what is more strange is when calculated
with the formula (dBS21 = 20 * log (abs (S21)), I get different values from those used in the graphic COMSOL dBS21 and the oscillatory beahavoir is present.
If Comsol used otherwise for caculation of dBS21 parameter please enlighten me, that the results did not close.
Please help me!