PAGE CONTENTS
Objectives
The objective of the Next Generation Antenna (NGA) programme is to generate a range of advanced antenna solutions which meet the evolving Ku and Ka Band market requirements for increased flexibility and performance whilst also increasing value for money.
Challenges
Key issues with the DMLS process for Ka band applications are:
- Surface roughness (although this is less of an issue at Ka band),
- Voids in the surface of the component (due to the density of the finish material),
- Thermal conductivity of Nickel-Bronze material,
- Electro-less plating of complex internal geometries (where electro plating is impractical due to the small apertures / cavities).
Plan
Development of the DMLS process and its associated materials to arrive at a robust technology for implementing microwave components.
An EQM Multi-feed assembly (based upon the Hylas requirements) will be the vehicle for demonstrating the suitability/qualification for space applications.
Current Status
Direct Metal Laser Sintering has been used to manufacture a single piece orthomode transducer (OMT – traditionally spark eroded in four or five pieces), which will be assembled with more conventionally produced components, such as a polariser and horn, to create an array of Ka band feedchains.
In order to reduce the poor insertion loss of a component made in a nickel/bronze material, silver plating of has been successfully carried out using an electroless plating process over a base of electroless nickel. Surface finish is critical to perfect plating.
A Mid term Review has been held and has shown good progress towards the qualification of the DMLS OMT with electroless silver plating. Manufacturing, testing and qualification activities are scheduled to start in the next few months.