ECRA Technology

ECRA: a disruptive strategic technology for Europe competitveness

Electric propulsion has been identified by European actors as a strategic technology for improving the European competitiveness in different space areas such as in-space operations and transportation. In recent years, ONERA has built up an expertise on the ECRA (Electron Cyclotron Resonance Accelerator) disruptive technology for electric propulsion, and the need for further maturation along with Europe’s search for new technologies lead to the MINOTOR project (MagnetIc NOzzle thruster with elecTron cyclOtron Resonance).

Principle of ECRA technology

Based on electron cyclotron resonance as the sole ionization and plasma heating process, ECRA is a cathodeless thruster with magnetic nozzle, allowing thrust vectoring. It has a significant advantage in terms of global system cost and reliability compared to mature electric propulsion technologies. It is also scalable and can potentially be considered for all-electric satellite platforms, from cubesats to space tugs.


principle of ecra
principle of ecra
  • The application of microwaves at electron cyclotron frequency heats the electrons immersed in a magnetic field
principle of ecra
  • Hot electrons ionize the neutral gas and push the resulting plasma out of the chamber
principle of ecra
  • Conversion of electron thermal and gyrokinetic energy into directed ion energy in the magnetic nozzle via the self-consistent electric field
principle of ecra
  • Ions are accelerated into a jet (dense plasma). The plasma jet is globally current free: cathodeless thruster




propulsor of ecra

Demonstrator of the ECRA thruster in operation