Thinned-array Curse

Thinned-array Curse

The thinned array curse (sometimes, sparse array curse) is a theorem in electromagnetic theory of antennas. It states that a transmitting antenna which is synthesized from a coherent phased array of smaller antenna apertures that are spaced apart will have a smaller minimum beam spot size (typically, the main lobe has a solid angle that is smaller by an amount proportional to the ratio of the area of the synthesized array divided by the total area of the individual apertures), but the amount of power that is beamed into this main lobe is reduced by an exactly proportional amount, so that the total power density in the beam is constant.

The origin of the term "thinned array curse" is not clear. Robert L. Forward cites use of the term in unpublished Hughes Research Laboratories reports dating from 1976.