The present invention relates to an antenna assembly for transmitting and receiving electromagnetic waves. More particularly, this invention relates to a wideband and multiband omnidirectional antenna assembly for sending and receiving radio waves. Specifically, this invention relates to a radiative antenna element formed by way of a single-fed spiraled sheet of conductive material. The conductive material is interlaced with a dielectric material to form the radiative element. The radiative element includes a height of substantially less than ¼ of the characteristic wavelength of the lowest operating frequency.