A method is disclosed for effectively reducing the radar cross section for external irradiation of an antenna arrangement. The method is particularly applied to an array of radiating elements. It is not necessary to reduce scattering from each element of the array. Instead each element is arranged to scatter with a phase and amplitude such that the combined backscattering from the complete array in a particular direction is minimized. This particular direction is typically towards the external (threat) source. An antenna arrangement is demonstrated in which radar signals are received by an array lobe, while shaping a reduced scattering pattern having a null appearing in the external radar direction and a reduced scattering pattern for any external illumination by introduction of an impedance member in the feed line of a number of the array elements. According to the invention this impedance load may further be systematically varied according to the requirements of each particular situation.