EOSOL Aerospace Develops an Omnidirectional Antenna for the ESA's A4UC Project
Successful completion of the first part of the verification campaign for the 7.5-metre VDEA antenna (VHF Deployable Antenna).
With the acceptance of the Test Readiness Board (TRB), the European Space Agency (ESA) has formally declared the first part of the VDEA (Very Wideband VHF Deployable Antenna) verification campaign formally completed.
The project, led by EOSOL Aerospace as prime contractor and in collaboration with Comet Aerospace SL, the Polytechnic University of Valencia, Aeroxess (Germany) and Open Cosmos (UK), has successfully passed the TRB milestone of the planned indoor verification phase, in which the deployment mechanism of the 7.5-metre long antenna, designed to operate at VHF frequencies, has been validated.
Antenna designed for detecting water and other resources underground from space
The deployable VDEA antenna, operating in the frequency band from 40 MHz to 50 MHz, has been developed as a payload for the future radar instrument that will enable the exploration of the Earth’s subsurface in polar and arid regions, with significantly higher capabilities than any existing instrument today. This technology will allow for the mapping of basal topography and ice thickness, analysis of the internal structure of the ice sheet, detection of the subglacial hydrological system, and determination of the melting/freezing regime at the base of ice platforms. Additionally, it will enable the mapping of aquifers in the Middle East and Sub-Saharan Africa.
With a diameter of 0.35 meters, the antenna is 0.4 meters long when folded. Once deployed, it reaches a length of 7.5 meters and features 9 dipoles-stations that ensure the necessary circular polarized radiation. The antenna weighs less than 8 kg.
The development of this solution has been made possible thanks to the collaboration between EOSOL Aerospace, responsible for the antenna design and integration; Comet Aerospace SL, in charge of integrating the deployable boom and deployment system; and the Polytechnic University of Valencia, which developed the feeding system. Following the integration of the breadboard, successful mechanical, modal, folding, and deployment verifications were carried out, demonstrating the expected functionality and electromagnetic robustness of the design.
Next challenge
The project has now entered the second verification phase, for which various auxiliary elements are currently being fabricated. The target is to verify the RF performance of the antenna. In the coming months, in collaboration with Aeroxess (Germany), radiation pattern measurements of the antenna will be carried out outdoor, using their innovative drone-based technology. These measurements are expected to take place before the summer of 2025.
This activity is funded by the European Space Agency under contract 4000141120/23/NL/VA.