An antenna includes at least two radiating arm structures made of or limited by a conductor, superconductor or semiconductor material. The two arms are coupled through a region on first and second superconducting arms such that the combined structure forms a small antenna with broadband behavior, multiband behavior or a combination thereof. The coupling between the two radiating arms is obtained via the shape and spatial arrangement thereof, in which at least one portion on each arm is placed in close proximity to each other (e.g., at a distance smaller than 1/10 of the longest free-space operating wavelength) to allow electromagnetic fields in one arm to be transferred to the other through close proximity regions. The proximity regions are spaced from the feeding port of the antenna (e.g., greater than 1/40 of the free-space longest operating wavelength) and specifically exclude the feeding port of the antenna.