Development of a VLF receiver system for Sudden Ionospheric Disturbances (SID) detection

Sudden Ionospheric Disturbances (SID) are transient changes in the ionosphere caused by enhancement in X-ray and EUV fluxes during solar flare events. The SuperSID space weather monitor has been developed by Stanford University Solar Center to detect SID via VLF remote sensing. In this paper, a receiver system named as UKM-SuperSID has been developed to detect SID in the equatorial region. The system, which consists of loop antenna, preamplifier and a computer, is able to detect VLF signals with frequency of 19.8 kHz transmitted from North West Cape station (NWC), Australia. The data obtained showed repetitive diurnal variation. During the observation period from 11 December 2011 until 17 January 2012, M and C class solar flares events have been detected, with a class M1.5 flare observed as the largest detected flare. The results showed that the effectiveness of the UKM-SuperSID in detecting SID in the equatorial region thus enables it to be part of the global space weather sensor network.