Antenna integrated into a compact conical nosecone.

A compact shallow cavity-backed discone antenna array for conformal omnidirectional antenna applications is disclosed. The antenna array comprises a plurality of discone antennas arranged in a ring array within a circular contoured conical cavity. The cavity is covered with an electrically transparent radome. The individual discone antenna elements are fed with coaxial transmission lines. Good performance is demonstrated by simulation and by experiment in terms of reflection coefficient and omnidirectional gain radiation patterns from about 960 MHz to 1220 MHz. In one embodiment, the shallow cavity-backed discone antenna array may be used as a flush-mounted antenna that conforms to the outer mold line of an aircraft.

A portable flat panel antenna system and method for using the same are disclosed. In one embodiment, the portable satellite antenna apparatus comprises a flat panel antenna and a container to house the antenna, the container having at least one radio-frequency (RF) transparent material through which the antenna is operable to transmit and receive satellite communications.

A nonplanar metamaterial polarizer includes: a substrate including dielectric material transmissive to electromagnetic radiation and having a nonplanar shape; a first conductive pattern on a first side of the substrate; and a second conductive pattern on a second side of the substrate. The first and second conductive patterns are configured to alter the polarization of the electromagnetic radiation as it transmits through the substrate. In some cases, the first and second conductive patterns include split-ring resonators, and the nonplanar shape is a cylinder. An antenna system includes the nonplanar metamaterial polarizer and an antenna inside or adjacent to the nonplanar metamaterial polarizer and configured to transmit or receive the electromagnetic radiation through the nonplanar metamaterial polarizer while the nonplanar metamaterial polarizer alters the polarization of the transmitted or received electromagnetic radiation. In some cases, the antenna is a monopole antenna, a dipole antenna, a biconical antenna, or a discone antenna.

In examples, systems and methods for waveguide antenna arrays with integrated filters are described. An example waveguide antenna array element a waveguide section has a first end and second end. The waveguide section is configured to propagate electromagnetic energy. The waveguide antenna array element also includes a feed configured to launch an electromagnetic wave into the first end of the waveguide section. The waveguide antenna array element also includes a waveguide filter having at least one waveguide cavity coupled to the second end of the waveguide section. The waveguide filter is configured to pass a first set of electromagnetic frequencies and reject a second set of electromagnetic frequencies. Yet further, the waveguide antenna array element includes an antenna coupled to the waveguide filter configured to radiate a portion of the electromagnetic energy passed by the waveguide filter.

Antennas such as flat panel, leaky wave antennas with directional coupler feeds and waveguides are disclosed. In one example, an antenna includes a surface having antenna elements, a guided wave transmission line, and a coupling surface. The guided wave transmission line provides a guided feed wave. The coupling surface is between and separates the guided wave transmission line and the surface having antenna elements. The coupling surface controls coupling of the guided feed wave to the antenna elements. The coupling surface can also spatially filter the guided feed wave to provide a more uniform power density for the antenna elements. The guided feed wave can be a high power density electromagnetic wave or a density radially decaying electromagnetic wave.

In an antenna including a dielectric window and a slot plate provided on one surface of the dielectric window, in a case where a reference position g is a center position in a width direction of each slot S and a center position in a length direction in the slot plate, the reference position g of each slot is located on a virtual circle centered on a center of gravity G0, and line segments connecting the reference positions g of the slots S and virtual point G1 to which the slots belong are located radially from a virtual point G1, angles (1 to 4) between adjacent line segments are equal to each other, and angles (1 to 4) formed by the length directions of the slots S at the reference positions g and the line segments to which the slots belong are equal to each other.

A non-circular center-fed antenna and method for using the same are disclosed. In one embodiment, the antenna comprises: a non-circular antenna aperture with radio-frequency (RF) radiating antenna elements; and a non-radially symmetric directional coupler to supply a RF feed wave to the aperture at a central location within the antenna aperture to enable the feed wave to propagate outward from the central location to an edge of the aperture.

A method and apparatus for impedance matching for an antenna aperture are described. In one embodiment, the antenna comprises an antenna aperture having at least one array of antenna elements operable to radiate radio frequency (RF) energy and an integrated composite stack structure coupled to the antenna aperture. The integrated composite stack structure includes a wide angle impedance matching network to provide impedance matching between the antenna aperture and free space and also puts dipole loading on antenna elements.

In examples, systems and methods for waveguide antenna arrays with integrated filters are described. An example waveguide antenna array element a waveguide section has a first end and second end. The waveguide section is configured to propagate electromagnetic energy. The waveguide antenna array element also includes a feed configured to launch an electromagnetic wave into the first end of the waveguide section. The waveguide antenna array element also includes a waveguide filter having at least one waveguide cavity coupled to the second end of the waveguide section. The waveguide filter is configured to pass a first set of electromagnetic frequencies and reject a second set of electromagnetic frequencies. Yet further, the waveguide antenna array element includes an antenna coupled to the waveguide filter configured to radiate a portion of the electromagnetic energy passed by the waveguide filter.