1. Department of Physics and Astronomy Clemson University Clemson SC USA
2. Department of Electrical and Computer Engineering University of Illinois at Urbana‐Champaign Urbana IL USA
3. Center for Geospace Studies SRI International Menlo Park CA USA
4. Earth and Atmospheric Sciences Cornell University Ithaca NY USA
5. Jicamarca Radio Observatory Instituto Geofísico del Perú Lima Peru