Abstract: A contrawound helical antenna produces a uniformly directed circulation of magnetic current with a plurality of magnetic dipole elements. In one embodiment, the magnetic dipole elements have the same curvature, and the magnetic currents on respective magnetic dipole elements are each directed in the same direction, relative to the central signal coupler of the magnetic dipole antenna. In another embodiment, the magnetic dipole elements have the opposite curvature, and the magnetic currents on respective magnetic dipole elements are each directed in opposite directions, relative to the central signal coupler of the magnetic dipole antenna.
Abstract: An electrically small broadband antenna comprises a plurality generalized contrawound toroidal helical antenna elements, each made from a single continuous conductor divided into two length portions each of which are substantially the same length and which have a generalized helical pattern, wherein the helical pitch senses the two length portions are opposite to one another, and the two length portions are insulated from one another and overlap one another on the surface of a generalized toroid. Each antenna element incorporates a signal coupler with an impedance matching network, wherein the first ports of the plurality of signal couplers are in proximate location to one another and are connected together to a common signal input port, and the second ports of the respective signal couplers are connected to the respective signal feed ports at the node locations where the respective length portions join one another, or at a diametrically opposite location.
Abstract: In an electromagnetic antenna a continuous conductor comprises a first length portion and a second length portion, the first and second length portions each having a first end and a second end whereby the first end of the first length portion connected to the second end of the second length portion at a first node, and the second end of the first length portion is connected to the first end of the second length portion at a second node.
Abstract: An electrically small antenna is disclosed that is constructed from a generalized contrawound toroidal helix made from a single continuous conductor divided into two length portions each of which are substantially the same length and which have a generalized helical pattern. The helical pitch senses the two length portions are opposite to one another. The two length portions are insulated from one another and overlap one another on the surface of a generalized toroid. A signal is fed to the antenna at a port defined by the node locations where the respective length portions join one another, or at a diametrically opposite point. At the fundamental mode of operation, the antenna is a half guided wavelength in circumference. The size of the antenna is further reduced because of the slow-wave properties of the underlying generalized contrawound toroidal helix.