i use HFSS to simulate the circular polarization microstrip patch antenna, the eRHCP is more 5dB,and eLHCP is about -3dB, but the axial ratio is 3dB. i want to know how to obtain the axial ratio from the eRHCP and eLHCP. and how to judge the circular polarization is good or not?
If your antenna is a RHCP antenna, only when the difference between
the RHCP and LHCP is more than 15dB, Can the axial ratio be lower
than 3dB. But in your case the difference is just 8 dB, I wonder
how the axial ratio is 3 dB. Can you post the plot?
in general, we only care about the axial ratio in the direction of main lobe, so you just take the angles for theta and phi in mainlobe direction. if in the main lobe range the axial ratio is good ,it's enough for you.
Hi, i wonder how did you calculate axial ratio with this expression: r=(|ERHCP+|ELHCP|)/(|ERHCP|-|ELHCP|). In my example, gain of RHCP is -2.65dB and LHCP 7.6dB. However HFSS shows the axial ratio 5.1dB. I cant find where is the problem, am i considering wrong variables in HFSS?
thanks