Here one very interesting antenna – La Fontenna Clone.
It was interesting what is inside FON antenna. On site specs they give it 7dbi or 6.5dbi with 3m low loss coax.
On one Italian blog I found dimensions for building a clone of La Fontenna.
I found two posts on this Italian blog :
blog.liberailvoip.it/fon-antenna-lanalisi-del-prodotto
La Fontenna inside :
And La Fontenna CLONE !
blog.liberailvoip.it cloniamo-la-fontenna
On site is also PDF and DWG with dimensions for building the PCB plate.
Here and some dimensions :
Reflector 120mm x 65 mm
PCB plate 71mm x 46mm
Distance between PCB and reflector 11mm
This clone of La fontenna gets ~ 5 dbi
For more info about building this antenna read the blog of the author.
For me this antenna is quite similar to Curtain Quad Antenna or it is some sort of biquad printed on pcb ?
Who can say ?