Abstract: A layer (30) absorbing transmitted radiation, placed between an antenna (10) and a radome (20) and extending parallel to the surface of the antenna at a close distance thereto, the absorption coefficient of said absorbing layer varying between a minimum value in the center of the radiating surface and a maximum value at the periphery of said radiating surface.The absorbing layer may in particular be formed by a central area (31) with a zero or virtually zero absorption coefficient surrounded by a peripheral area (32) with a constant absorption coefficient. It may also be formed by a succession of concentric areas exhibiting respective absorption coefficients increasing from the center to the periphery.In addition to the reduction of the radome effect, said structure reduces significantly the radar cross section of the assembly when the latter is the target of a radar.