Dual-Polarized, Wideband, Lightweight P-band Antenna Element and Array

The P-band antenna array is built from rows and columns of antenna elements for the purpose of allowing beam steering up to the maximum desirable angle without incurring grating lobes in the radiation patterns. For flexible mission planning, a large array can be built from several of the small, panel-like elements. The elements are deployable from a folded or stacked stowed configuration during launch, arranged side by side during operation. Each antenna element is itself a fully functional small antenna array. The number of panels can be chosen as dictated by the mission objectives and budget. Three geometries were designed and tested. Geometry 1 features non-planar metal structures with minimal dielectric support, where the back cavity is closed. Geometry 2 features non-planar metal structures with minimal composite sheet dielectric support, but with an open cavity. Both geometries avoid large flat sheets, which are vulnerable to bending, thereby increasing the mechanical stiffness of the structure while using only thin sheet metal and maintaining an exceptionally low mass-to-size ratio. Geometry 3 features planar metal structures, with sandwich composite dielectric support and an open cavity. While it does not benefit from the mechanical stiffness utilized in non-planar designs, the planar sandwich structure increase robustness and reduces the cost of fabrication. All element geometries have wideband capabilities and are dual polarized. Although designed for space and planetary exploration, the P-band antenna is also valuable for various terrestrial use cases. The P-band antenna array is at technology readiness level (TRL) 5 (component and/or breadboard validation in relevant environment) and is available for patent licensing. Many critical science objectives demand the capability to penetrate meters of dust and regolith to reveal buried terrain. While NASA’s primary focus includes the Moon and Mars, future missions targeting Venus, Mercury, asteroids, and other celestial bodies will also require technologies capable of deep subsurface penetration, mapping sub-surface features at meter-scale resolution. For the Space Exploration Synthetic Aperture Radar (SESAR) mission, NASA scientists needed a lightweight, beam-agile synthetic aperture radar (SAR) operating at P-band frequencies to achieve these objectives on the Lunar and Martian surfaces. Innovators at NASA’s Goddard Space Flight Center have developed a dual-polarized, wideband, lightweight P-band antenna element and array for spaceborne radar applications. The antenna array utilizes lightweight, low-profile elements that serve as modular building blocks, forming “array panels” that can be scaled up into larger, multi-panel arrays. The novel design features a mostly planar conductor geometry paired with a robust, lightweight composite material construction. The antenna element and array design are also scalable to other frequencies (e.g., L-, S-, C-, or X-bands) for radar applications where low mass and beam agility are crucial.