Abstract: 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) ...

Abstract: Ionospheric heating by high-power high frequency (HF: 3–30 MHz) electromagnetic waves has been an emerging technique to generate very low frequency (VLF: 3–30 kHz) signals in recent decades.