Three-dimensional antenna array

A three-dimensional antenna array (100) comprises a series of pairs (106, 108, 110, 112, 114, 116, 118, 120) of electrically conductive plates, the plates of each pair being connected by a planar array of individual antenna elements forming a two-dimensional sub-group of elements. Radiation emitted by individual antenna elements of a given sub-group is confined to the plane of that sub-group over a confinement area defined by the pairs of plates. The output direction (102) of the array may be controlled by independently controlling the components of the direction in the (xy) plane of the sub-groups and normal to the plane. By confining radiation output by any given sub-group of elements to the (xy) plane of that sub-group over a confinement area in that plane, the obstruction of radiation within the array by individual antenna elements, signal feed lines and other components is reduced compared to prior art three-dimensional arrays in which individual antenna elements radiate directly in three dimensions.