ECE system on ASDEX-upgrade placed inline at the high power waveguide based transmission system

It is proposed to provide the Electron Cyclotron Emission (ECE) feedback signal for MHD control experiments along the ECRH line-of sight. Experiments on TEXTOR have demonstrated a proof of principle [1], [2] and [3] motivate the further development and the implementation of such an ECCD aligned ECE system for NTM control in larger fusion machines. Implementation of such a system on ASDEX-Upgrade [4], based on waveguides equipped with a fast directional switch, is presented in this paper [6]. First results of open loop control of MHD modes in TEXTOR were presented in [2, 7].