Far Field Data

Altair Forum User

After reading the Getting Started and User Manual there are a number of Antenna Far Field parameters that I cannot find how to calculate:

 

- Front/Back and/or Front/Rear as a function of frequency

- Beamwidth to -3dB levels

- Main Lobe/Side Lobe ratio

- Antenna Temperature (T) and G/T as a function of frequency

 

I could get some of these manually from a Far Field diagram, but a numerical output from the program would be more practical.

 

Would be most grateful if someone can help.

 

 

JIF

Hello FEKOFan,

 

You are indeed correct that these parameters are not currently available in numeric form. Since annotations are not automated in POSTFEKO yet, they will have to be calculated yourself. I'll add a feature request as you suggested so that this can be implemented in FEKO direction in the future. The problems that we have had with these parameters in the past is that they are easy for calculated, based on some assumptions such as the existence of a main beam and side lobes. However, this does not exist for all antennas and then these parameters can't be evaluated. It also depends on what points (of the far field) the user included in the request.

 

If you calculate these from far field DataSets, you can get them in numerical form. You could use the DerivedResults module (see shared/lua/DeriveResults/docs/modules/DeriveFarField.html in the FEKO installation folder for some documenation) to easily calculate the gain and other parameters and from that derive the quantities that you seek. If you do write some nice scripts, share it here with the rest of the FEKO community. ;-)

JIF

The DerivedResults module in the 2018 version (soon to be released) has a DeriveSourceAnnotation module that does the same calculations as the annotations.