An antenna having a plurality of ports coupled to at least one radiator opening or protuberance formed on a metallic surface. A plurality of modulators are coupled to the plurality of respective ports and configured to modulate phase or amplitude of a plurality of signals radiated at the plurality of respective ports. A combiner is configured to combine the modulated signals to substantially cancel power reflected from the plurality of respective ports, wherein the plurality of respective ports are functionally aggregated into a single port.