Abstract: An omni-directional antenna can include a feed disk, which can terminate at a feed disk apex, and a top element, which can include a nipple that terminates a top element apex. The feed disk and top element can be positioned so that the feed disk apex and the top element apex can be spaced-apart by a distance “d”, which can be chosen according to the desired frequency range and cable feed impedance. The feed disk and top element can also have respective bottom conical and top conical surfaces. When the feed disk and top element are positioned, the top and bottom conical surfaces can establish a respective first predefined angle relative to a horizontal plane and a second predefined angle relative to the horizontal plane, thereby extending the antenna frequency range. The predefined angles can be chosen according to the desired frequency range of operation and cable feed impedance.

Abstract: A broadband antenna can include a parabolic dish having a diameter D and a radius of curvature that establishes a focal point for the parabolic dish. A tapered slot feed having a feed point can be positioned above the parabolic dish so that its effective radiation point is spaced a distance F from the center of the dish, where F is the focal length of the dish. With this configuration, feed point for the tapered slot feed can be coincident with parabolic dish focal point. The tapered slot feed can include two elements that form an exponentially tapered slot, which establishes a phase center for the tapered slot feed. A conductive bar can interconnect the two elements, in order to minimize the phase center variation during broadband operation.

Abstract: A broad band antenna uses a bicone antenna configuration as a feed transformer and exponentially tapered reflector fins to radiate the antenna's energy. The bicone antenna design is used to match the antenna's impedance to coaxial cable impedance. The fins function to reduce the traditional bicone antenna diameter. Reflection between the cones and the attached reflector fins as well as return loss are reduced by wrapping the reflector fins with metallic foil.