I took inspiration for this antenna from this blog post but i made some modifications.
https://lucsmall.com/2017/02/06/making-antennas-for-1090mhz-ads-b-aircraft-tracking/
I changed that design so 69mm radial length counts from the center of the lid, not from the edge.
I used SMA instead of F connector.
The lid i used is 85mm in diameter.
The author marked this model as their own original creation.