High stability large reflectors for Ka band

In the context of an ARTES 5 ESTEC/ESA programme, EADS CASA Espacio (ECE) has performed a development able to meet and excel the demanding requirements for the telecommunications reflector antenna. The crucial requirement for the emergent Ka-band is the high surface accuracy involving the manufacturing errors and the in-flight distortions, as the major sources of degradation and impairments of the communications systems. The new technology, which guarantees adequate performances in flight, is demanded for commercial products devoted to multibeam communications systems, therefore aspects like planning, costs and reliability are of primary importance and have been taken into account in the program development. This paper summarises the results obtained during the last milestone of the program where a 2.4 m diameter deployable reflector has been manufactured and qualified as the engineering model. The hardware has been submitted to a complete test campaign, where the behaviour of the reflector has been satisfactory verified. In previous stages of the program, meaningful tasks such as the requirement definition, trade off solutions, baseline design and sample and breadboard level test campaigns have been performed. It has been the main objective to have a design allowing the use of an automated manufacturing process. Whit this purpose, the whole reflector concept for both dish and back structure is a sandwich configuration. Where, CFRP honeycomb core and high modulus fibre for the skins appeared adequate candidates. The core is a standard market product, but the skins have been studied to be manufactured by using the automatic Fibre Placement machine in order to have a recurrent, light, adaptable and industrialized product.