Abstract: A radome uses traditional continuous heating wires mixed with detuned dipoles between heating wires and can be placed at any chosen distance from an array antenna or FSS. The continuous heating wires add a reactive component to the incident field phase, which is effectively cancelled out by the detuned dipoles which provide a capacitive component. The orthogonal components of the incident field are transmitted with very small losses over a wide number of scan angles. These heating and detuned dipoles can be printed on low loss dielectric materials. In addition, the printed elements of this radome can be scaled to operate over a chosen frequency band.

Abstract: An antenna system includes a ground plane and/or antenna elements forming an antenna array. A spatial filtering surface is positioned adjacent the antenna array through which electromagnetic radiation to or from the antenna array passes. The spatial filtering surface includes a dielectric substrate and a plurality of spaced, geometric configured, resonant elements printed on the dielectric substrate and configured and spaced from each other to have a resonant frequency to filter an electromagnetic field at a selected frequency with respect to an angle of incidence to the dielectric substrate. A dielectric filler is positioned between, above and below each resonant element printed on the dielectric substrate. A spatial filter taper transform is imparted when electromagnetic radiation passes therethrough. A standing wave is created between the ground plane and spatial filtering surface.

Abstract: A feed structure (105) for a horn antenna (100). The feed structure can include a first waveguide (110) and a second waveguide (115) having a first portion at least partially disposed within the first waveguide. The second waveguide also can include a second portion intersecting a first wall (240) of the first waveguide. The first wall can include a first frequency selective surface (244) at an intersection (280) of the first wall and the second portion of the second waveguide. The first waveguide can be operatively coupled to a first horn section (130) and the second portion can be operatively coupled to a second horn section (135).

Abstract: A spatial filtering surface includes a dielectric substrate and a plurality of spaced, geometrically configured, resonant elements positioned on the dielectric substrate. The resonant elements form concentric rings that each attenuate any electromagnetic radiation passing therethrough a different amount wherein a spatial filter transform is imparted for tapering the magnitude and phase of a produced aperture field.

Abstract: An antenna (100) for microwave radiation including a first horn (135) which includes a plurality of corrugations (150). At least one of the corrugations (150) is formed of a frequency selective surface (FSS) (138). The FSS has a plurality of FSS elements (305) coupled to at least one substrate (310). The substrate (310) can define a first propagation medium such that an RF signal having a first wavelength in the first propagation medium can pass through the FSS (300). The FSS (300) is coupled to a second propagation medium such that in the second propagation medium the RF signal has a second wavelength which is at least twice as long as a physical distance between centers of adjacent FSS elements (305).

Abstract: Method for dynamically optimizing radome (110) performance. The method can include the steps of sensing (405) at least one parameter defining a performance characteristic of the radome (110). At least one electrical characteristic of the radome (110) can responsively be varied to dynamically modify the performance characteristic. For example, the electrical characteristic can be varied by application of an energetic stimulus (440) to the radome (110).

Abstract: A method for dynamically modifying electrical characteristics of a radome (110). The method can interpose a radome (110) in the path of a radio frequency signal (140). At least one electrical characteristic of the radome (110) can be selectively varied by applying an energetic stimulus to dynamically modify a performance characteristic of the radome (110). Electrical characteristic can include a permittivity, a permeability, a loss tangent, and/or a reflectivity. The energetic stimulus can include an electric stimulus, a photonic stimulus, a magnetic stimulus, and/or a thermal stimulus.

Abstract: A waveguide (100) including at least one outer surface (105, 110, 115, 120) defining a waveguide cavity (140) and at least one inner surface (130, 135) positioned within the waveguide cavity (140). The inner surface (130, 135) includes a frequency selective surface (FSS) having a plurality of FSS elements (145) coupled to at least one substrate. The substrate defines a first propagation medium such that an RF signal having a first wavelength in the first propagation medium can pass through the FSS (130, 135). The FSS (130, 135) is coupled to a second propagation medium such that in the second propagation medium the RF signal has a second wavelength which is at least twice as long as a physical distance between centers of adjacent FSS elements (145). The second wavelength can be different than the first wavelength.

Abstract: A spatial filtering surface includes a dielectric substrate and a plurality of spaced, resonant dipole elements positioned on the dielectric substrate. Each dipole element has dipole ends and an associated diode for controlling amplitude taper and a reflection phase of an electromagnetic field at a selected frequency with respect to an angle of incidence to the dielectric substrate. Bias lines interconnect the dipole elements for conducting a bias current to a dipole element.

Abstract: A spatial filtering surface includes a dielectric substrate and a plurality of spaced, resonant dipole elements positioned on the dielectric substrate. Each dipole element has dipole ends and an associated diode for controlling amplitude taper and a reflection phase of an electromagnetic field at a selected frequency with respect to an angle of incidence to the dielectric substrate. Bias lines interconnect the dipole elements for conducting a bias current to a dipole element.

Abstract: An antenna system includes a ground plane and/or antenna elements forming an antenna array. A spatial filtering surface is positioned adjacent the antenna array through which electromagnetic radiation to or from the antenna array passes. The spatial filtering surface includes a dielectric substrate and a plurality of spaced, geometric configured, resonant elements printed on the dielectric substrate and configured and spaced from each other to have a resonant frequency to filter an electromagnetic field at a selected frequency with respect to an angle of incidence to the dielectric substrate. A dielectric filler is positioned between, above and below each resonant element printed on the dielectric substrate. A spatial filter taper transform is imparted when electromagnetic radiation passes therethrough. A standing wave is created between the ground plane and spatial filtering surface.

Abstract: A spatial filtering surface includes a dielectric substrate and a plurality of spaced, geometrically configured, resonant elements positioned on the dielectric substrate. The resonant elements form concentric rings that each attenuate any electromagnetic radiation passing therethrough a different amount wherein a spatial filter transform is imparted for tapering the magnitude and phase of a produced aperture field.