an issue about Directivity

[microantenna]

this shows the relationship between gain and A,my antenna frequency is 15.6GHz,A=35,4*pi*35/(300/15.6)^2=1.22，convert it to db is a very small value,can anyone tell me how to deal with it,or how to assess the gain of an antenna using its area

--- Updated Jan 6, 2025 ---

this shows the relationship between gain and A,my antenna frequency is 15.6GHz,A=35,4*pi*35/(300/15.6)^2=1.22，convert it to db is a very small value,can anyone tell me how to deal with it,or how to assess the gain of an antenna using its area

 

[volker@muehlhaus]

The effective antenna aperture Aeff in your equation is not identical to the area of your patch antenna. That only works for horn antennas and similar aperture antennas.

 

[microantenna]

The effective antenna aperture Aeff in your equation is not identical to the area of your patch antenna. That only works for horn antennas and similar aperture antennas.

can you tell me what can substitude patch antenna's Aeff

 

[volker@muehlhaus]

I would not even try to estimate Aeff, and simply simulate gain.

That said, your model looks strange. The patch has a small microstrip notch for microstrip feed that you have not used, and it seems that you try a probe feed instead. From your screenshot it is not clear if that is modelled properly, with only the center conductor passing through the substrate and touching the pad.

I recommend to look again at tutorials on patch antenna modelling.