Polarization current antennas comprise a dielectric radiator that extends along a z-axis, polarization devices that are positioned adjacent the dielectric radiator along the z-axis that are configured to polarize respective portions of the dielectric radiator and a feed network that is configured to excite the polarization devices with an RF signal to generate a polarization current wave that propagates in the z-axis direction through the dielectric radiator, with acceleration, at (1) a first variable speed that does not decrease as the wave moves along a first portion of the dielectric radiator and that does not increase as the wave moves along the remainder of the dielectric radiator, (2) a second variable speed that does not decrease as the wave moves along the entirety of the dielectric radiator or (3) a third variable speed that does not increase as the wave moves along the entirety of the dielectric radiator.

This document describes techniques and systems for planar surface features for achieving antenna coverage. A structure is configured to provide a feed network for propagating electromagnetic energy along an energy path formed under a planar surface. The planar surface includes a recessed cavity with walls surrounding a cavity floor embedded within the planar surface. The cavity floor is shaped to form radiating slot(s) open through the structure to the energy path under the planar surface. A ridge feature protrudes from the planar surface on either side of the recessed cavity with a ridge length that is parallel with the cavity walls and a ridge height set to prevent cross-interference near the radiating slot within the cavity floor, thereby narrowing coverage for the electromagnetic energy within the feed network.

This document describes techniques and systems for planar surface features for achieving antenna coverage. A structure is configured to provide a feed network for propagating electromagnetic energy along an energy path formed under a planar surface. The planar surface includes a recessed cavity with walls surrounding a cavity floor embedded within the planar surface. The cavity floor is shaped to form radiating slot(s) open through the structure to the energy path under the planar surface. A ridge feature protrudes from the planar surface on either side of the recessed cavity with a ridge length that is parallel with the cavity walls and a ridge height set to prevent cross-interference near the radiating slot within the cavity floor, thereby narrowing coverage for the electromagnetic energy within the feed network.

Generally discussed herein are systems, devices, and methods that include a communication cavity. According to an example a device can include substrate with a first cavity formed therein, first and second antennas exposed in and enclosed by the cavity, and an interconnect structure formed in the substrate, the interconnect structure including alternating conductive material layers and inter-layer dielectric layers.

Generally discussed herein are systems, devices, and methods that include a communication cavity. According to an example a device can include substrate with a first cavity formed therein, first and second antennas exposed in and enclosed by the cavity, and an interconnect structure formed in the substrate, the interconnect structure including alternating conductive material layers and inter-layer dielectric layers.

A feed assembly for a parabolic dish reflector is described. The feed assembly includes a waveguide cavity locatable at the focal point, or any other desired off-boresight location corresponding point, of the parabolic dish, at least one first radiating element optimized for operation at a first frequency band and provided on a top surface of the waveguide cavity, and a plurality of second radiating elements each optimized for operation at a second band of frequencies and provided on the top surface of the waveguide cavity.

A feed assembly for a parabolic dish reflector is described. The feed assembly includes a waveguide cavity locatable at the focal point, or any other desired off-boresight location corresponding point, of the parabolic dish, at least one first radiating element optimized for operation at a first frequency band and provided on a top surface of the waveguide cavity, and a plurality of second radiating elements each optimized for operation at a second band of frequencies and provided on the top surface of the waveguide cavity.

A Cubesat uses both rail rods, walls, or both as an antenna. Either the rail rods and/or walls may form a rectangular waveguide, and may have one or more slots that allow energy to leak and radiate in a predefined direction in space.

An antenna assembly includes: an antenna including: a metal signal layer having a radiating surface; and a feed port; and a waveguide surrounding the antenna and configured to guide electromagnetic energy transmitted from the radiating surface in a direction away from the antenna; and a controller module connected to the feed port and configured to drive the antenna to transmit electromagnetic energy from the radiating surface; wherein the antenna, waveguide, and controller module are configured such that, when the controller module drives the antenna, the transmitted electromagnetic energy matches a reception characteristic of an implantable device and is sufficient for the implantable device to create one or more electrical pulses of sufficient amplitude to stimulate neural tissue of a patient, solely using electromagnetic energy received from the antenna, when the implantable device is located at least 10 centimeters away from the antenna.

An antenna assembly includes: an antenna including: a metal signal layer having a radiating surface; and a feed port; and a waveguide surrounding the antenna and configured to guide electromagnetic energy transmitted from the radiating surface in a direction away from the antenna; and a controller module connected to the feed port and configured to drive the antenna to transmit electromagnetic energy from the radiating surface; wherein the antenna, waveguide, and controller module are configured such that, when the controller module drives the antenna, the transmitted electromagnetic energy matches a reception characteristic of an implantable device and is sufficient for the implantable device to create one or more electrical pulses of sufficient amplitude to stimulate neural tissue of a patient, solely using electromagnetic energy received from the antenna, when the implantable device is located at least 10 centimeters away from the antenna.