An antenna assembly including: an insulating substrate; a conductive coating covering a surface of the substrate at least section-wise and serving at least section-wise as a planar antenna receiving electromagnetic waves; a first coupling electrode electrically coupled to the conductive coating extracting useful signals from the planar antenna; a source of interference disposed such that interfering signals can be received by the planar antenna; an electrically conductive ground; and a second coupling electrode electrically coupled to the conductive coating coupling out interfering signals received by the planar antenna from the planar antenna. The second coupling electrode includes a first coupling surface and the conductive structure includes a second coupling surface capacitively coupled to the first coupling surface, the two coupling surfaces configured to selectively allow passage of a frequency range corresponding to the interfering signals to be extracted from the planar antenna.