Harry36 provided a slot dipole as an antenna for drones:
I designed a similar antenna for 1.7 to 2.7 GHz which gives a good gain and low swr over the communication band. Somewhere here or on Lan23 i see a picture of something similar with slots at the end so i also used them. For everyone who wants to recalculate such an antenna you will find the cst file below. I think for its simplicity it performs very well.
Size:
CST
slot antenna max band.cst