Folks,
Just a tip for the unwary.
Don't confuse GBAS and GRAS (ain't acronyms accurate).
The way I understand it, GBAS is the new name for LAAS, the limited area cousin of WAAS, and works with a wide range of existing production equipment.
GRAS is quite different, and requires a VHF datalink to a suitably equipped aircraft, I don't think the GBAS mentioned in Germany has much to do with the GRAS Airservices is promoting.
The total number of available GRAS receivers suitable for GA aircraft is precisely zero, in contrast to WAAS as GBAS.
If I misunderstand, I am certain somebody will point it out.
Tootle pip!!