Abstract: n this paper,a design technique of 2-D soparabl3 multi-step amplitude quantization low sidelobe apert ure distribution with exponent restraint for airborne solid-state active phased arrays is proposed. It i3 shod n that this method is' effective to reduce the peak sidelobe levels in horizontal plane and other areas and the kind of T/R modules. Using 2-D separable design idea, the number kinds of column feeding networks can be greatly reduced in engineering application. The. computer simulated results confirm the theoretical analysis.