Abstract: Provided herein are various enhanced antenna structures for radio frequency communications. In one example, an antenna a spiral antenna element having a single arm configured to couple to a radio frequency link at a central node. The antenna also includes a ground element comprising a conical frustum sharing an axis at the central node of the spiral antenna element and configured to couple to a ground reference for the radio frequency link.

Abstract: Provided herein are various enhancements for electronically scanned arrays (ESAs) and performance thereof. In an example implementation, an apparatus is provided that includes an ESA and a dielectric lens applied to the ESA. The dielectric lens includes a domed arrangement formed from dielectric material. The dielectric lens advantageously allows beam scan operations performed by the ESA across a directional range to achieve a target performance over a target bandwidth.

Abstract: Provided herein are various enhancements for antenna systems and directed radio frequency energy structures. In one example, an apparatus includes an antenna array comprising a plurality of Vivaldi antenna elements arranged about an axis perpendicular to a baseplate. Feed elements are coupled to each of the Vivaldi antenna elements through the baseplate. First alternating ones of the Vivaldi antenna elements are configured to transmit radio frequency (RF) energy at a first RF band, and second alternating ones of the Vivaldi antenna elements are configured to receive RF energy at a second RF band.

Abstract: Provided herein are various enhancements for antenna systems and directed radio frequency energy structures. In one example, an apparatus includes an antenna array comprising a plurality of antenna elements formed by waveguide structures embedded within a substrate and positioned about a longitudinal axis of the substrate to form at least two concentric ring arrangements of antenna elements. Apertures of the waveguide structures are configured to emit or receive radio frequency (RF) energy generally along the longitudinal axis. Feed elements are coupled to each of the waveguide structures on an end opposite of the apertures, and configured to couple the RF energy for the antenna array.

Abstract: Provided herein are various enhancements for antenna systems and directed radio frequency energy structures. In one example, an apparatus includes a baseplate, an antenna array comprising a plurality of Vivaldi antenna elements arranged about an axis perpendicular to the baseplate, and feed elements coupled to each of the Vivaldi antenna elements through the baseplate.

Abstract: Provided herein are various enhancements for antenna systems and directed radio frequency energy structures. In one example, an apparatus includes an antenna array comprising a plurality of antenna elements formed by waveguide structures embedded within a substrate and positioned about a longitudinal axis of the substrate to form at least two concentric ring arrangements of antenna elements. Apertures of the waveguide structures are configured to emit or receive radio frequency (RF) energy generally along the longitudinal axis. Feed elements are coupled to each of the waveguide structures on an end opposite of the apertures, and configured to couple the RF energy for the antenna array.

Abstract: A reflector antenna includes a reflector having a curved reflecting surface that extends around a longitudinal center axis, wherein the curved reflecting surface is defined by rotating a concave curve around the longitudinal center axis and wherein one end of the concave curve defines an apex on the longitudinal center axis. The reflector antenna may further include a ground plane extension having a flat reflecting surface abutting an edge of the reflector and extending radially away from the longitudinal center axis. A phased array feed may be arranged spaced apart from and opposite to the reflecting surfaces of the reflector and the ground plane extension. A tapered collar may be arranged adjacent to the phased array feed, wherein the tapered collar tapers outward away from the phased array feed and towards the reflector, and wherein the tapered collar comprises an inner reflective surface facing the reflector.

Abstract: Provided herein are various enhanced antenna structures for radio frequency communications. In one example, an antenna includes a single-arm spiral antenna having an antenna element configured to couple to a radio frequency link at a central node of the spiral. A ground element is disposed proximate to the central node of the spiral and configured to couple to a ground reference for the radio frequency link.

Abstract: An antenna element includes a radiator element, a plurality of feed circuits and a multiplexing interface. The radiator element can transceive radio-frequency (RF) signals. The feed circuits, which include impedance and multiplexing features, are realized on multiple feed locations of the radiating element feed slot. The multiplexing interface is electrically coupled to the plurality of feed circuits and can multiplex a number of sub-band signals associated with the feed circuits. The multiplexing interface can provide a high isolation between the feed circuits.

Abstract: A spiral antenna device includes one or more conductive spiral arms that are formed on a dielectric substrate attached to a wall of a cylindrical cavity. One or more coils are formed on the wall of the cylindrical cavity and are coupled to the one or more conductive spiral arms. Starting points of the one or more conductive spiral arms are in a center region of the dielectric substrate and ending points of the one or more conductive spiral arms are electrically coupled to first ends of the one or more coils.

Abstract: A communications system such as a global position system (GPS) device, a spacecraft tracking device, a handheld radio, or any other communications device may include one or more helix antennas. Each helix antenna may include a conductive circular ring at a distal end of one or more helical arms. In a helical antenna with multiple arms, the arms may be shorted together at the distal end by the conductive circular ring.

Abstract: A radio-frequency (RF) antenna with wideband impedance matching includes a first conductive layer, a second conductive layer, and patterned connections. The first conductive layer is formed on a first surface of a dielectric material. The second conductive layer is formed on a second surface of the dielectric material. The patterned connections between the first conductive layer and the second conductive layer are formed through multiple vias to enable the wideband impedance matching. The first conductive layer and the second conductive layer are formed based on an antenna-layout pattern. The multiple vias are formed based on a via pattern that corresponds to the antenna-layout pattern.