August 16, 2016


Carmen-4 is the mission name of a Carmen architecture under development and planned to be launched aboard the GSAT-19 geostationary satellite from ISRO (GEO). For this mission, Carmen-4 is only composed of an ICARE-NG instrument.

For Carmen-4 mission, CNES is the prime contractor and tasked EREMS with the ICARE-NG flight model development and manufacturing.

Mission Objectives

The Carmen-4 instrument has particular mission objectives as well as objectives related to the satellite:

  • Scientific objectives: to measure charged particle fluxes and their effects on test electronic components.
  • Host satellite associated objectives: to characterize the local radiative environment and to evaluate the potential drifts of the equipment, in particular due to radiation from the South Atlantic Anomaly (SAA), and to contribute to the instrument cross calibration in the frame of the JRE (Join Radiation Experiment).

Carmen-4 / GSAT-19 MissionPerformances
High Energy EnvironmentICARE-NG
Particle flux Measurement
  • electrons
  • protons
Fast counting ~3E5 cnts/s
250 keV – 4 MeV
8 - 100 MeV
Radiation Effects on EEE partsICARE-NG
  • Dosimetry
  • On-board Environment Characterization
  • Total Dose Effects
  • Non destructive Single Events
  • Destructive Single Events (with protections)

~10 -¹ rad
Parameter Drifts
some ev./d, @1 s
some ev./wk, @1 s

Carmen-4 mission performances

Description and Features

The ICARE-NG/Carmen-4 instrument is composed of a data acquisition unit (SPECTRE) for the set of three radiation detectors and the component test bed (EXPERIENCE Module or MEX) recurrent from those of Carmen-1.

The radiation detectors are made of silicon fully depleted solid state detectors used in single and coincident mode. The SPECTRE unit performs the radiation spectrum measurement on various energy ranges. The on-board measurements consist in accumulating energy loss spectra in the junctions over a programmable accumulation period.

The reference levels of the discriminators, the gain of the amplifiers, and the accumulation time are programmable and provide possible on-board tuning optimization. The reference values are preset before launch.

In addition to the on-board acquisition, the SPECTRE unit carries out the functions of power distribution and communication interface via a 1553 bus. It also includes an interface to control one or more external instruments. In the case of Carmen-2, this capability is not used.

The objective of the EXPERIENCE module (MEX) is to measure the flight event rates and the parametric drifts of an advanced electronic component set. This module is slave of the SPECTRE unit of which it depends for power and data exchanges.

The main characteristics of the Carmen-4 instrument are the following:

Dimensions200 x 118 x 96 mm
Mass2.4 kg
Power Consumption (according to operating mode)6 W to 12 W
Telemetry Data Rate420 bits/s
Data Volume4.32 Mo/day

Main features of the ICARE-NG/Carmen-4 instrument