Amplitude-Probability Distribution Model for VLF/ELF Atmospheric Noise

This paper presents an analytic model for VLF and ELF atmospheric-noise amplitude-probability distributions (APDs). The APDs are governed by two parameters that can be determined at the receiver-one characterizing the impulsivity of noise from local sources and the other characterizing the ratio of energy in the impulsive-noise component to the energy in the non-impulsive background-noise component. The derived expression explicitly shows the dependence of the APD on the earth-ionosphere-waveguide propagation constant. Calculated APDs are presented for ambient and nominally disturbed ionospheric conditions.