How we can generate the mask with ADS in aim to fabricate a patch antenna

Gerber ? DXF ? GDSII ? There are many exporters in it..

a file that I can read with altium viewer or cadence

Altium can read Gerber or DXF format.

Is that possible for cadence? I've tried to export a DXF file with ADS the import it with cadence , but I don't know why the button "import" was desactivated !

I could'nt do this. Have u any idea how we can pass from ads to cadence

many thanks

You don't probably have license to import DXF files..