Sensitive Broadband ELF/VLF Radio Reception With the AWESOME Instrument

A new instrument has been developed and deployed for sensitive reception of broadband extremely low frequency (ELF) (defined in this paper as 300-3000 Hz) and very low frequency (VLF) (defined in this paper as 3-30 kHz) radio signals from natural and man-made sources, based on designs used for decades at Stanford University. We describe the performance characteristics of the Atmospheric Weather Electromagnetic System for Observation, Modeling, and Education (AWESOME) instrument, including sensitivity, frequency and phase response, timing accuracy, and cross modulation. We also describe a broad range of scientific applications that use AWESOME ELF/VLF data involving measurements of both subionospherically and magnetospherically propagating signals.