Ultra broadband antenna having asymmetrical shorting straps

摘要

An antenna includes a liner shaped to fit over a helmet; a first RF element attached to the liner; a second RF element attached to the liner so that the first and second RF elements are separated by a gap; an RF feed electrically connected to the first RF element for providing RF energy to the first RF element; a ground feed electrically connected to the second RF element; a first shorting strap that is electrically connected to the first and second elements opposite from the RF feed; and a second shorting strap electrically connected to the first and second RF elements between the first shorting strap and the RF feed. The shorting straps are used to generally match the impedance of the antenna to an electrical device such as a transmitter, receiver, or transceiver. A matching circuit may be connected in series between the first RF element and the RF feed to further refine matching the antenna impedance to the electrical device. In another embodiment of the invention, the RF elements may be mounted directly to the helmet, in applications where the helmet is made of a dielectric material.