A Single Feed per Beam Antenna Product

Status date

The scope of the study is the design and manufacture of a Feed Block Assembly (FBA), for Multiple Spot Beam antennas (MSA) using the Single Feed Per Beam (SFPB) concept.

The cost of the conventional design approach to SFPB Feed Assemblies is high, even when customising an existing design concept for a new mission. This study aimed to use innovative design approaches, in combination with existing technologies, to offer a significant improvement in mission specific customisation costs.


The FBA product cannot be a single universal design since the layout and scale of these SFPB feed arrays varies significantly from mission to mission.

The best which can be achieved is a modular design approach which is adaptable to as wide a range of missions as possible, with the minimum amount of mission-specific design effort. The key tasks were therefore:-

  • Production of generic specification
  • Design activities to justify generic components, standard interfaces and modular approach.
  • Test plan to validate qualification approach for generic components
  • Justification of the generic component qualification environments through the full EQM testing.

This development delivers a new design approach for Feed Arrays for SFPB antennas, which offers a significant cost improvement over the products previously available on the market.

The simpler and more modular design approach also allows shorter manufacturing cycle times.

 There are also potential spin-off benefits from the application of some of the involved technologies and methodologies, e.g.:

waveguide panels or ‘manifolds’

    1. reduction of loading on existing suppliers of conventional fabricated waveguides (typically a critical issue on Ka-band SFPB spacecraft).
    2. Potential applications in other areas of the spacecraft – e.g. payload. 

A block diagram showing the principal components of a typical SFPB Antenna is shown below:

A 21 feed cluster configuration was chosen for the EQM, after being identified as typical of a real mission need. The EQM FBA included 4 functional EQM user-gateway (U/G) feed chains, and 1 functional EQM RF sensing (RFS) feed chain. 

The FCHM consists of:

  • A box structure consisting of 2 parallel support plates with 4 side panels.
  • 2 Tx waveguide manifolds one on either side.
  • 2 Rx waveguide manifolds one on either side.
  • Flexible waveguides linking feed chains to waveguide manifolds.
  • Support brackets interfacing with spacecraft.


The project ran from late 2010 to mid 2014.

The design, analysis, manufacture and test of the generic feed chain products was carried out by the Airbus Defence and Space Antenna Group in Ottobrunn, Germany. The feed chains were qualified at unit level, for an environment which should envelope the needs of future commercial projects

The qualified feed chains were then built into the FCHM EQM, designed by the Airbus Defence and Space Antenna Group in Stevenage, UK. The combined FBA product was then qualified by testing in a representative MFSA configuration.


The objective of the project is to design and manufacture an Equipment Qualification Model (EQM) of a Feed Block Assembly (FBA) for future Ka Band Single Feed Per Beam (SFPB) antenna programmes.

The project includes the development of generic designs of feed chain for user/gateway and RF sensing applications, and a modular design approach for the Feed Cluster Housing Module (FCHM), which together will offer a step improvement in cost effectiveness relative to the current state of the art.

 The project uses the knowledge gained from earlier ARTES funded feasibility study phases to manufacture and test the chosen design concept, and provide full qualification heritage for future projects.

Current status

This development is now complete.  The final review was held at ESA on 24th September 2014