Satellites require a suitable antenna for line of sight microwave communication with the ground. Disclosed here is an Archimedean spiral antenna backed by a copper cavity containing quadruple conical perturbations. The antenna meets the required size, mass, transmitting power, bandwidth, and circular polarization for a satellite (e.g., CubeSat) environment while providing immunity to the mounting position.

A multibeam antenna is provided comprising a direct radiating array, DRA, and a reflector arranged to reflect signals radiated from the DRA in a transmission mode and to reflect signals to the DRA in a reception mode. The antenna is a very high throughput satellite (VHTS) antenna providing global coverage with narrow, high gain beams.

Wireless communication method and apparatus to enable communications between a plurality of endpoints and a satellite or terrestrial gateway integrated with a plurality of oblong shaped antenna arrays. The wireless communication method leverages data symbols that are orthogonally modulated. The method permits the use of a plurality of compact oblong shaped antenna arrays to increase network capacity and reduce endpoint power consumption.

The disclosed embodiments relate to the design of a system that implements a reflectarray antenna. The system includes a time-modulated metasurface, which is configured to act as a planar reflector for an electromagnetic wave that is radiated by a feeder into free space at an operation frequency f.sub.0. The time-modulated metasurface includes time-modulated unit-cells that provide a nonlinear conversion between f.sub.0 and another desired frequency f.sub.d. The system also includes a phase-delay mechanism, which adjusts a phase delay by acting on a phase applied to a modulation frequency f.sub.m that modulates each unit-cell. The nonlinear conversion and the phase-delay mechanism operate collectively to facilitate angle-independent nonreciprocity by imposing different phase gradients during up-conversion and down-conversion processes, and by preventing generation of certain propagative harmonics due to total internal reflection.

Antennas and methods for using the same are described. In one embodiment, the antenna comprises an aperture having a plurality of radio-frequency (RF) radiating antenna elements, the plurality of RF radiating antenna elements being grouped into three or more sets of RF radiating antenna elements, with each set being separately controlled to generate a beam at a frequency band in a first mode.

A satellite including an antenna assembly adjustable between a stowed configuration and a deployed configuration. When in the stowed configuration, the antenna assembly can be stowable within a container, such as a container compatible with a CubeSat. When in the deployed configuration, a reflector of the antenna assembly can be directionally adjustable, such as in both elevation and azimuth.

A satellite in accordance with the present teachings has plural “thin” (i.e., panel-like) segments, which are coupled together and extendable along the in-track direction of movement of the satellite. One or more of these segments, which is advantageously an antenna panel, has the ability to “roll” relative other segments. This enables the satellite to establish and maintain direct pointing of the antenna panel to a targeted area on the ground. The antenna panel includes linear, electronically steerable array.

An antenna array may include shielding elements that provide a degree of radiation shielding to other components of the antenna array, such as a substrate of the antenna array. In some examples, the shielding elements may be positioned to overlap with one or more gaps between antenna elements, or one or more gaps between ground elements (e.g., when viewed from a radiation source, when viewed in a direction perpendicular to a substrate). Thus, shielding elements of an antenna array may reflect, absorb, or otherwise dissipate radiation that passes through such gaps before the radiation is incident on the other components of the antenna array, such as the substrate of the antenna array.

Synthetic aperture radar transmit and receive antenna systems and methods of transmitting and receiving radar signals are disclosed. In one embodiment, a transmit and receive antenna system includes a transmit antenna array configured to transmit a plurality of radio frequency transmit signals, the transmit antenna array including a plurality of patch antenna elements mounted to a printed circuit board, each patch antenna element belonging to a subarray, and one or more power amplifiers, each power amplifier feeding a subarray of the patch antenna elements, and a reflectarray receive antenna configured to receive radio frequency signals including a plurality of reflectarray antenna elements mounted to a printed circuit board, at least one antenna feed configured to receive radio frequency signals reflected from the plurality of reflectarray antenna elements, and at least one low noise amplifier electrically connected to the at least one antenna feed.

Technologies directed to overlaid shared aperture array with improved total efficiency are described. One RF structure includes a first antenna with a first set of antenna elements disposed on a first plane of a support structure and a second antenna with a second set of antenna elements disposed on a second plane of the support structure. A set of parasitic antenna elements are disposed on the first plane. Two adjacent antenna elements, including one from the first plurality of antenna elements and another one from the plurality of parasitic antenna elements, are separated by the second distance.