July 19, 2016



Argos-4 project general organisation is as follows:

  • CNES is directly responsible for the system and for the definition of the space segment and ground segment with the supply of the on-board instrument to the satellite prime contractor.
  • CLS is the system operator by CNES delegation. It is responsible for distributing to the users the data collected by the beacons, and for sending directions or messages to the beacons. It ensures the routine operational exploitation of the on-board instruments.

CNES is responsible for the on-board equipment until the in-flight commissioning phase with CLS as technical support. The responsibility transfer occurswhen CNES declares the on-board equipment to be operational.

CLS is then responsible for in-orbit monitoring and on-board instrument monitoring with CNES's technical assistance.


The Argos mission is subjected to several cooperation agreements between CNES and its three partners, NOAA (National Oceanic and Atmospheric Administration) for the USA, Eumetsat for Europe and ISRO (Indian Space and Research Organisation) for India.

These agreements are applicable if the Argos-3 instruments are installed respectively on board the POES, Metop, and SARAL satellites. For Argos-4, the agreements are formalized with NOAA and Eumetsat to set up the CNES instruments on board the Polar Free Flyer satellite for NOAA and Metop-SG satellite for Eumetsat.

The cooperation protocol for Argos is generally as follows:

  • CNES has the technical responsibility for the on-board instrument development, the support for the integration to the satellite, and post-launch operations.
  • CLS has CNES delegation for the responsibility of the Argos-4 ground segment development. There is no payment for this activity for the Argos-4 project; CNES's responsibility is therefore limited to the validation of the interfaces between the on-board segment and the ground segment.
  • The partner is responsible for platform development, Argos instrument integration on the platform, launch, the satellite's command/control ground segment, and data distribution to the Argos mission ground segment.

Operations Committee

The Argos Operations Committee (OPSCOM) aims to:

  • oversee the development and the exploitation of the Argos data collection system;
  • review and approve the requests for applications emitted by the potential platform operators for the Argos system use;
  • review and approve the price rates for the scientific data processing by the Argos data processing system;
  • solve the problems that could arise related to the implementation and operation of the Argos system.

The Agencies contributing to the space segment of the Argos data collection system are considered "Participating Agencies" (to this day, CNES, NOAA, EUMETSAT and ISRO are Participating Agencies) and appoint a co-president of the Argos Operations Committee. The Agencies preparing a future contribution to the space segment of the Argos system are considered observer members (it was the case for ISRO until SARAL launch).

The decisions taken by the OPSCOM are recorded in the consolidated report of the OPSCOM.