Validation of a low cost gnss receiver for ionospheric total electron content monitoring at the periphery of the south atlantic magnetic anomaly: a two week commissioning dataset from mthatha, south africa

Abstract

This paper presents commissioning results from MTHA-SA, a low cost dual frequency Global Navigation Satellite System (GNSS) receiver station installed at Walter Sisulu University in Mthatha, South Africa (31.59°S, 28.78°E; L ≈ 1.9). The station occupies a scientifically strategic position at the eastern periphery of the South Atlantic Magnetic Anomaly (SAMA), filling a 340 km observational gap in the regional ionospheric monitoring network. Two weeks of continuous observations during October 1–14, 2024 are analysed to evaluate measurement accuracy, operational reliability, and preliminary ionospheric characterisation. Vertical total electron content (VTEC) derived from carrier smoothed code observations shows agreement within 0.18–0.23 TECU against the Sutherland IGS reference station during geomagnetically quiet conditions (Kp ≤ 3), with a correlation coefficient of r = 0.978. During the moderate geomagnetic storm of October 10–11, 2024 (Kpmax = 6, Dstmin = −78 nT), the station captured storm enhanced density features with inter station TEC deviations remaining below 0.31 TECU. Data availability across GPS, GLONASS, Galileo, and BeiDou constellations averaged 95.8% over the commissioning period. Enhanced day to day TEC variability (coefficient of variation: 18.3%) relative to the Sutherland reference (CV: 12.9%) provides preliminary evidence for SAMA influenced ionospheric behaviour at this transitional geomagnetic latitude. The total installation cost of USD 1,900 represents approximately 12% of equivalent scientific grade infrastructure, offering a replicable model for expanding ionospheric monitoring across African universities.