Antenna system

An antenna system comprising:

• an electrically conductive surface that comprises an electrically conductive medium;
• a recess that is located inside the electrically conductive surface, as a result of which the electrically conductive surface acts as a periphery of the recess;
• at least one first electrically conductive crosspiece, which originates on a first side of the periphery and is electrically conductively connected to the periphery and protrudes into the recess and extends in the direction of a second side, facing the first side, of the periphery and there ends with the periphery, forming a gap, as a result of which the recess is divided into a first part and a second part and the gap that connects the two parts;
• at least two electrical lines, of which a first electrical line originates in the first part of the recess at a first feed point, located at or near the first crosspiece but electrically separate from it, and a second electrical line originates in the second part of the recess at a second feed point located at or near the first crosspiece but electrically separate from it;
• the first electrical line extends in the first part of the recess in the direction of the periphery and is capacitively coupled to the periphery, and the second electrical line extends in the second part of the recess in the direction of the periphery and is capacitively coupled to the periphery,
• wherein the first feed point is connectable to or connected to a first gate of a feeder device, and the second feed point is connectable to or connected to a second gate of a feeder device, and the feeder device supplies a first feed point and the second feed point with a common-mode signal and/or a push-pull signal.