Abstract: One embodiment provides a method for receiving parallel rays at a lens. A first surface of the lens can receive first substantially parallel rays incoming from a first direction. The first surface of the lens also can receive second substantially parallel rays incoming from a second direction that is substantially different than the first direction. The lens can focus the first substantially parallel rays onto a first focal point on a second surface of the lens and focus the second substantially parallel rays onto a second focal point on the second surface of the lens, the second focal point being different than the first focal point.

Abstract: One embodiment provides for a gradient lens having a first substantially hemispherical member comprising a first convex surface and a base and a second substantially hemispherical member projecting away from the base of the first hemispherical member and comprising a second convex surface. The gradient lens also includes a plurality of gradient layers disposed within the first hemispherical member, each gradient layer concentrically aligned to the first hemispherical member and comprising an index of refraction different than that of adjacent gradient layers.

Abstract: A gradient lens capable of focusing electromagnetic rays received at a first lens surface onto a second lens surface. The first lens surface and second lens surface can include convex surfaces protruding in opposite directions from a substantially planar surface. The lens can include a gradient index between the first surface and the planar surface and a gradient index between the two convex surfaces. The lens can include two or more gradient layers, each gradient layer having an index of refraction different than that of adjacent gradient layers. The gradient layers can focus parallel electromagnetic rays incident on the first surface onto a focal point at the second surface of the lens. As the parallel electromagnetic rays pass from one gradient layer to the next, the rays are redirected toward the focal point.

Abstract: A broadband bicone antenna supports frequency selective control of electrical length. Frequency selective control of the electrical length of an antenna can provide an antenna exhibiting two or more different electrical lengths where use of each length depends upon the operating frequencies of the signals. The electrical length of the bicone antenna may be reduced in response to higher operating frequencies. Such reduction in electrical length at higher frequencies can provide improved antenna radiation patterns for the antenna. Further, the electrical length of the bicone antenna may be increased in response to low frequency operation. Such increase in electrical length may improve VSWR performance at lower frequencies. Simultaneous operation of the bicone antenna at varied electrical lengths for varied frequency bands can provide improved broadband performance of the antenna.

Abstract: A gradient lens capable of focusing electromagnetic rays received at a first lens surface onto a second lens surface. The first lens surface and second lens surface can include convex surfaces protruding in opposite directions from a substantially planar surface. The lens can include a gradient index between the first surface and the planar surface and a gradient index between the two convex surfaces. The lens can include two or more gradient layers, each gradient layer having an index of refraction different than that of adjacent gradient layers. The gradient layers can focus parallel electromagnetic rays incident on the first surface onto a focal point at the second surface of the lens. As the parallel electromagnetic rays pass from one gradient layer to the next, the rays are redirected toward the focal point.

Abstract: An antenna system with an improved antenna feed system is discussed. This multi-beam antenna system can produce a beam of electromagnetic energy propagating in a desired direction by emitting multiple beams of electromagnetic energy that constructively and destructively interfere. The direction of the net beam of electromagnetic energy can be controlled by adjusting the phase and amplitude of the emitted beams of electromagnetic energy which in turn influences the constructive and destructive interference. The phase and amplitude adjustments can be determined by sampling coordinate rotation or similar functions. Aliased components of these functions can be particularly useful in element reduction.

Abstract: A high impedance bicone antenna system supporting ultra wideband operation. The antenna may comprise a reduced aperture size and reduced half-angles of the conductive cones forming the antenna. Reduction in cone angles may increase the impedance of the cones. An impedance matching mechanism for interfacing to the high impedance bicone may be positioned within one of the cones by a dielectric material. The impedance matching mechanism may be a flat conductive taper functioning as an impedance matching transmission line between an external feed line and the antenna. The conductive taper may function as a center conductor of a coaxial feed mechanism where the inside of the cone around the taper serves as the outside conductor, or return, of the tapered feed. The geometry of the cones may be modified to provide one or more end segments that are substantially cylindrical.

Abstract: A broadband omni-directional bicone antenna. The antenna can comprise conductive surfaces of conical voids provided within a solid dielectric structure. The outside surface of the solid structure can support a radio frequency (RF) lens geometry operable for beam forming. The beam forming can modify the elevation pattern of the electromagnetic radiation from the bicone antenna. The solid dielectric structure may be machined or molded from a single piece of material. The conical voids provided within the solid structure can be metallized to provide conductive bicone radiators. The outer surface beam shaping lenses can be zoned or continuous and can provide elevation patterns with increased gain, cosecant squared falloff, or various other patterns. The beam shaping lens may be formed from any low-loss dielectric. Alternatively, the lens may be formed from a less dense material such as dielectric foam that can support radial conductive beam forming vanes.

Abstract: A broadband bicone antenna supports frequency selective control of electrical length. Frequency selective control of the electrical length of an antenna can provide an antenna exhibiting two or more different electrical lengths where use of each length depends upon the operating frequencies of the signals. The electrical length of the bicone antenna may be reduced in response to higher operating frequencies. Such reduction in electrical length at higher frequencies can provide improved antenna radiation patterns for the antenna. Further, the electrical length of the bicone antenna may be increased in response to low frequency operation. Such increase in electrical length may improve VSWR performance at lower frequencies. Simultaneous operation of the bicone antenna at varied electrical lengths for varied frequency bands can provide improved broadband performance of the antenna.

Abstract: A broadband bicone antenna system supports improved VSWR operation of a high-impedance bicone antenna having a reduced aperture size, high input impedance at the central vertex of the cones, one or more pattern tuning filters associated with the cones, and input filtering for frequency selective impedance matching. Pattern tuning filters can improve the radiation pattern at different frequencies by controlling the electrical length of the antenna in response to the frequency components of the associated wideband signal. Impedance matching input filters can improve the signal matching to couple radio frequency energy into the antenna system from a feed line. Mutual tuning of the pattern tuning filters; the impedance matching input filters; and the impedance of the bicone antenna itself can improve the overall voltage standing wave ratio (VSWR) performance of the bicone antenna system over a broad range of operating frequencies.