1. Leibniz Institute of Atmospheric Physics at the University of Rostock Kühlungsborn Germany
2. Department of Electrical and Computer Engineering and Coordinated Science Laboratory University of Illinois at Urbana‐Champaign Urbana IL USA
3. The Arctic University of Norway Tromso Norway
4. Space Sciences Laboratory University of California, Berkeley Berkeley CA USA
5. Radio Observatorio de Jicamarca Instituto Geosfísico del Perú Lima Peru
6. MIT Haystack Observatory Westford MA USA