The innovation refers to a microstrip antenna which is made up of several layers, one lying on top of another. Against a first ground plane layer (1) which is made up of a block layer for electro-magnetic radiation lies a first substrate layer (2) and against this a longitudinal feed line (3) which extends in a plane parallel to the first ground plane layer (1). Against the feed line (3) and the first substrate layer (2) lies a further second substrate level (4) and against this a second ground plane layer (5). This is furnished with a slit (6) which extends perpendicular to the length direction of the feed line (3). A third substrate layer (7) lies against the second ground layer (5) which forms the microwave signal coming from the feed line (3) through the slit (6) and the third substrate layer (7).
