TEC variations at GPS stations over high — Latitude and at the equatorial region

This paper analyzes and compares TEC measurement at GPS stations belonging to UKM installed at Husafell, Iceland (64° 40´ N, -21° 1´ E) in the high-latitude and UKM (2° 55´ N, 101° 46´ E) in the equatorial latitude. A high performance dual-frequency GPS receiver with chock-ring antenna was used in this study. GPS data for the whole year of 2009 were used in this analysis. BGS´s Bernese Processing Engine (BPE)´s precise point positioning (PPP) mode was used to generate TEC at the single station with the zero-difference technique for differencing level of choice. Comparison of the maximum value of TEC between Husafell, Iceland for high-latitude and UKM, Malaysia for the equatorial region was carried out. Results show that the maximum value of TEC at high-latitude reaches its maximum at post local noon which is similar to that over the equatorial region. TEC values reach their maximum at 13:00 UTC at Husafell while at UKM it is at 06:00 UTC (14:00 LT). It is observed that TEC at UKM´s equatorial station is approximately twice compared to the Husafell station.