Patent ID: 8674890
Filing Date: 2014-03-18
Classification: H01Q

Abstract:
1. A multiband antenna structure comprising: a raised base having a raised coaxial feed comprising an inner signal conductor and conductive coaxial shield surrounding the inner signal conductor; a first radiating element extending from the base along a majority of the length of the antenna structure and having a first resonance, the first radiating element galvanically connected with the raised coaxial feed; an impedance matching element, providing distributed impedance matching, comprising the conductive coaxial shield formed in the base, a base coil connecting the first radiating element with the raised coaxial feed, and a conductive sheath surrounding a portion of each of the conductive coaxial shield, the base coil, and the first radiating element; and a second electrically floating radiating element having a second resonance distinct from the first resonance; wherein the conductive sheath has an opening through which the second electrically floating radiating element is capacitively coupled with the base coil in a radial direction of the antenna structure; and wherein the length of the antenna structure is less than about ¼ of the wavelength of a lowest operating frequency.