Tuneable microstrip scatterer

New class of controlled reflective type antenna arrays is considered. These arrays are executed as integrated chips. The proposed structures are a kind of microstrip diffraction arrays. The microstrip radiators may have an arbitrary shape. Each radiator contains controlled elements (crystal diodes). Changing the diodes´ bias voltages varies the array electromagnetic characteristics. This digital diffraction array has a set of microwave radar images. Such arrays are capable of being applied to a radar-tracking environment.