European Space Agency

Modular Payload Demonstrator (MPD)


The objective of the project is to develop a means of mounting a number of matrix power amplifiers (MPAs) into a common mechanical and thermal assembly for mounting onto a payload with the overall aim of reducing RF losses and payload AIT cost.


The key issues to be addressed by this project were:

  • Development of a payload mounting structure.

  • Development of MPA mounting techniques.

  • Mechanical testing of the overall structure.

  • Thermal testing of the overall structure.

  • RF testing to measure losses and compare with heritage assembly techniques.


It has been demonstrated that the modular approach could provide quicker, easier (lower cost) assembly and test of the entire MPA payload, and that it would be capable of operating with 1dB lower RF losses and hence either increased performance or a lower DC requirement.


The aim is to reduce payload volume, RF losses, differences between the MPAs and AIT time and thus manufacturing cost. By using a common MPA assembly technique in a linear assembly fashion it is possible to reduce the assembly time and complexity. Packing density may be increased, reducing satellite floor space and reducing RF losses and thus improving overall payload performance.


The project kicked-off as a CCN in November 2004.
A BDR was held in May 2005, and CDR in February 2006; the project was closed in summer 2006.

Current status

The project kicked-off on 17 November 2004, passed BDR, and was stopped at CDR when the modelling predicted that a second iteration of the mounting structure would be required.

Status date

Tuesday, November 22, 2011 - 13:51