Description
The ground based Automatic Identification System (AIS) is a coastal tracking and messaging system used by vessels for maritime traffic monitoring. The European SAT-AIS initiative aims at providing a space-based complementary system to extend the range of the existing AIS to high seas via VHF satellite constellation. The AIS Miniaturized Antenna (AISMAN) activity concentrates on the development of a VHF array antenna for mini-satellite platforms in Low Earth Orbit. Array element volume minimization and mass reduction are considered performance drivers due to the in-orbit array deployment and satellite mass requirements. Artificial Magnetic Materials (AMM) have been chosen as design concept of the baseline array element due to the significant size reduction they can offer. Further technical solutions, such as slotted ground plane, combined with AMM, have allowed for an outstanding profile reduction, while preserving high radiation efficiency and low back radiation. Innovative testing methodologies have been specifically developed to handle truncation errors and echo signals while performing radiation pattern measurement of the array on a full-scale mock-up platform in a hemispherical automotive NF range. This activity covered a trade-off on possible element designs, an array antenna trade-off and performance validation as well as a manufacturing and validation campaigns at single element and array level. A contract extension was awarded to investigate alternative manufacturing technologies and processes, leading to the manufacturing and testing of an additional engineering model based on a multi-layer stack assembly with metallic parts printed on a thin film material (Kapton substrate) and bonded to a core material made from RF transparent Kevlar Honeycomb.
