STUDY OF VERY LOW FREQUENCY/EXTREME LOW FREQUENCY (VLF/ELF) WAVE IN A.C ELECTRIC FIELD STUDY OF VERY LOW FREQUENCY/EXTREME LOW FREQUENCY (VLF/ELF) WAVE IN A.C ELECTRIC FIELD

Abstract

ELF/VLF stands for Extremely Low Frequency and Very Low Frequency, and refers to the range 300 Hz to 30 kHz. We're talking about radio waves, like the AM/FM signals you get, just at an even lower frequency. Communications with submarines immersed in the conducting sea necessitated the use of VLF waves and later ELF waves, with their comparatively large skin depths in salt water. This need for navigation and communications with submarines and the need for reliable global military communications was the indirect driving force behind most of the developments in VLF and ELF radio wave propagation theory and experiment over the last 50 years.