The present invention relates to antenna systems. Technical result of the invention is providing operation of two-polarization antenna manufactured on the basis of planar metal-dielectric waveguide in wide range of frequencies. The technical result is achieved by the fact that the antenna comprises a planar metal-plated, at least on one side, dielectric waveguide to the side walls of which two metal waveguides joined with the planar waveguide via periodical array of slots are connected, wherein the array comprises two slots shifted or inclined with respect to each other, and wherein radiating elements having two symmetry planes are placed in nodes of a rhombic mesh on a surface of the planar waveguide.