The Observation of Ionospheric Large-Scale Wave Structure In Southeast Asia

The occurrence of the equatorial plasma bubble (EPB) at nighttime always leads to the scintillation and fluctuation of radio wave signals from satellites. The observation in the seeding perturbation of EPB is important to understand the seeding mechanism of EPB. In this paper, a large-scale wave structure (LSWS) formed at the bottom side of the F layer is studied using GNU Radio Beacon Receiver (GRBR) that receives data from Communications/Navigation Outage Forecasting System (C/NOFS). The LSWS was determined from the high variations of total electron content (TEC) along the path of C/NOFS to GRBR. The study shows that LSWS component was developed around the E-region sunset (SSE) for both days on December 2012 and April 2013 and only the day from April 2013 showed the presence of nighttime EPBs after the development of LSWS. The results show that the LSWS may be present during the late evening with no occurrence of EPB in the post-sunset. However, the results can be verified by investigating more beacon data and the minimum amplitude of LSWS to develop EPBs.