European Space Agency

Multiple Feeds per Beam Feed System


The proposed feed system will allow to create a four colour multi spot beam Ka-band scenario using only one reflector for transmit and one for receive.

Thanks to the saving of two large reflectors compared to a single feed per beam approach, the new feed system also allows to realise mixed missions (eg. multi spot beams in Ka-band plus contoured high power beams Ku-band) on large space crafts.

The new feed system is also an ideal solution for expensive large unfurlable reflectors (>5m), which are required for multi spot beam scenarios with very small beam diameters (eg. 0.2°).

The objective of the project is to design, manufacture, test and qualify a multiple feeds per beam feed system for the Ka transmit band. The principle can also be used for other frequency bands, for example Ku or C-band.


State of the art four colour multi spot beam scenarios need four Tx size antennas. Using the proposed feed system this can be reduced to one Tx size and one Rx size antenna. Reduction of cost and mass can be achieved and an easier accommodation becomes possible.


A four colour multi spot beam scenario can be provided using only one reflector to transmit and one reflector to receive.


The feed system provides 18 overlapping spot beams in Ka transmit band and has RF sensing capabilities in Ka receive band.


The project started in September 2010 and is scheduled for two years. PDR was successfully held on February 15, 2011 and CDR is scheduled for September 2011. After the CDR, manufacturing will start. The start of the measurement campaign is planned for May 2012.

Current status

  • Scenario and antenna geometry is defined,
  • Horn and polariser design is finished,
  • BFN topology is defined,
  • PDR is completed.

Status date

Thursday, February 27, 2014 - 08:47