A stacked patch antenna is expandable from a thinner stowed configuration in which the gaps between the conductor layers are reduced, to a thicker deployed configuration in which the gaps are expanded to their required dimensions. The expansion mechanism can include rotation of threaded rods, pneumatic expansion of telescoping rods, and/or injection of a gas, a chemical sublimate, and/or an expandable foam into the gaps. In embodiments, the stowed thickness of the antenna can be approximately equal to the sum of the thicknesses of the conductor panels. In some of these embodiments high dielectric layers are not included. In other of these embodiments high dielectric layers are formed by filling gaps with a high dielectric foam. Embodiments implement aperture coupling to the stacked patch antenna. An array of the stacked patch antennae can be folded about a satellite until deployment, and can be planar when unfolded and deployed.