Described embodiments include an antenna and a method. In an embodiment, the antenna includes a holographic aperture having a surface including a plurality of individual electromagnetic wave scattering elements distributed thereon with a periodic inter-element spacing equal to or less than one-half of a free space wavelength of an operating frequency of the antenna. The aperture is configured to define at least two selectable complex radiofrequency electromagnetic fields on the surface with tangential wavenumbers up to 2π over the aperture element spacing (k_apt=2π/a). In an embodiment, the holographic aperture includes an amplitude and phase modulation holographic aperture. In an embodiment, each electromagnetic wave scattering element has a respective electronically controllable electromagnetic response to an incident radiofrequency electromagnetic wave, and the plurality of individual electromagnetic wave scattering elements are electronically controllable in combination to define the at least two selectable complex radiofrequency electromagnetic fields on the surface.