I think I found two mistakes in the calculation of gain patterns and HPBW in
http://www.openems.de/gitweb/?p=openEMS ... ads/master
The first is:
theta_HPBW = thetaRange(find(nf2ff.E_norm{1}(:,1)<max(nf2ff.E_norm{1}(:,1))/2,1))*2;
Should be:
theta_HPBW = thetaRange(find(nf2ff.P_rad{1}(:,1)<max(nf2ff.P_rad{1}(:,1))/2,1))*2;
The second is:
E_far_normalized = nf2ff.E_norm{1} / max(nf2ff.E_norm{1}(:)) * nf2ff.Dmax;
Doesn't give correct patterns. If the output should be power gain then it should read something like:
P_far_normalized = (nf2ff.E_norm{1} / max(nf2ff.E_norm{1}(:))) .** 2 * nf2ff.Dmax;
If the output should be voltage gain then it should read something like:
E_far_normalized = nf2ff.E_norm{1} / max(nf2ff.E_norm{1}(:)) * sqrt(nf2ff.Dmax);
Normalized gain patterns, HPBW
Moderators: thorsten, sebastian
Re: Normalized gain patterns, HPBW
Hi,
thanks for looking into this and I think you are right.
Sebastian what do you think?
Maybe we also need to create an example with a known result to test these figures. Maybe an inf. dipole? Or what kind of antennas would have an analytic result to validate against?
regards
Thorsten
thanks for looking into this and I think you are right.
Sebastian what do you think?
Maybe we also need to create an example with a known result to test these figures. Maybe an inf. dipole? Or what kind of antennas would have an analytic result to validate against?
regards
Thorsten
Re: Normalized gain patterns, HPBW
Hi,
I had a look at the Hertzian dipole example (found in examples/antennas/infDipole.m).
I modified it but it is obvious, that you only get the correct 90° HPBW if you use 1/sqrt(2).
See attachment.
Regarding the normalized Efield or "power" pattern you are right as well: http://en.wikipedia.org/wiki/Directivity
I will fix both in the Helix example.
regards
I had a look at the Hertzian dipole example (found in examples/antennas/infDipole.m).
I modified it but it is obvious, that you only get the correct 90° HPBW if you use 1/sqrt(2).
See attachment.
Regarding the normalized Efield or "power" pattern you are right as well: http://en.wikipedia.org/wiki/Directivity
I will fix both in the Helix example.
regards
 Attachments

 infDipol.m
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