The Large Deployable Antenna (LDA) A Review of Thermal Aspects 2005-01-2985
Several last-generation and future satellite communication systems require the use of large deployable antennas. A European product in this field is presently not available: in this frame the European Space Agency assigned a contract for the development of the Large Deployable Antenna Reflector for advanced mobile communications (LDA). The project is driven by ALENIA SPAZIO as prime contractor and system designer with the support of other companies: EGS (Russia), HTS (Switzerland), SENER (Spain), Magna (Austria).
The Antenna consists of a paraboloid with 12m in projected aperture, 6.3m of focal length and located with a clearance of 3m from the focal axis.
From a technical point of view, the LDA project was characterized by several challenging tasks: thermal aspects are outlined in the paper.
In particular, the mathematical modeling of the reflector and the optical characterization of its reflecting mesh required particular care. Critical thermal deflection requirements related to the long support arm had to be managed and special attention had to be dedicated in the simulation to the related thermal-distortion analysis.
In parallel to the system-level activities carried out by Alenia, a detailed subsystem model of the reflector dish has been developed at the Bauman Moscow State Technical University. An original approach based on finite-elements procedures and specifically dedicated to thermal modeling of large-scale on-orbit structures has been adopted.