STD15S-mk2 Infrared Earth Sensor

Status date

The project developed an improved version of existing Infrared Earth Sensor (IRES) for GEO multimedia satellite application, named STD15S-mk2.

This renewed IRES is a variant of an already in flight 1553 version (onboard EUROSTAR3000 and EXPRESS-AM satellites).

The goal of this additional development is an improvement of the in flight version towards a significantly cheaper version, keeping unchanged flight heritage upon several key elements (mechanism, design detection concept) as a conservative and general cost mastered approach.

STD15S-mk2 Infrared Earth Sensor

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The key issue was the schedule, in order to be able to provide this cheaper version of Infrared Earth Sensors onboard GEO satellites market as soon as possible.


The technology conversion to SMT allows for a significant cost oriented modification favourable to EUR3000 competitiveness with limited risks as this technology is already flight proven on many others projects at EADS Sodern.

This development allows SODERN to maintain and improve the Infrared Earth Sensor product line.

This development is implemented by EADS Sodern with EADS Astrium support as a main Prime Contractor for such equipment.

In order to reach this recurring cost reduction goal, the replacement of through hole EEE parts on each of the IRES boards by Surface Mounting Technology (SMT) components was rapidly identified as a very attractive upgrade.

All boards concerned are:

  • Z1 board dedicated to DC/DC power conversion and MIL-STD1553 communication,

  • Z2 board dedicated to Earth Signal processing,

  • Z3 Board dedicated to Motor control.
This electronic renew also brought the advantage of obsolescence correction in the same process in order to extend availability to prime contractors as long as possible with this product line.

Electronic boards conversion with SMT components will permit the implementation of available simplifications thanks to this technology:

  • Two costly custom hybrids dedicated to detector first processing will be replaced by standards SMT components,

  • Two single 1553 Hybrids transceivers will be changed by a cheaper dual transceiver now available and also flight qualified.

Taking into account the end customers real need throughout in flight use heritage for years with this product line, several additional simplifications will be introduced (additional cost saving induced by second rotational speed capability definitely removed from the boards).


The project developed and built new SMT boards to be mounted, as an upgrade, in the existing product line EQM renamed for that occasion STD15S-NG. A delta-qualification was conducted throughout dedicated environment testing (EMC, ESD, Thermal environment, Vibration check). Unchanged mechanical parts permitted however to keep advantage of previous costly mechanical qualifications (for mechanism lifetime, shocks).

The project was implemented on a 26 month schedule with a qualification completion date for July 2007.

Current status

Kick off occurred on 27/04/05. Qualification was reached on 27/07/2007. Final Presentation held on 15/11/2007 at ESTEC.

Up to now, 18 IRES STD15S-mk2 flight models are already contracted out of which 14 IRES for identified satellites with delivery dates from 2007 to 2009.