Study of sporadic E using daytime GHz scintillation observations in the equatorial region

The occurrences of 1.5 GHz daytime scintillations were recorded simultaneously at the Universiti Kebangsaan Malaysia (UKM) and a station at Langkawi during November and December 2010. The characteristics of daytime GHz scintillation and their relationship with E-region irregularities in the equatorial region were investigated. Ground-based measurements of scintillation were analyzed together with those of amplitude scintillation from Global Navigation and Satellite System (GNSS) radio occultation (RO) observations. Ground-based scintillation observations showed that strong amplitude scintillation with the S4 index exceeding 0.6 was frequently observed at UKM, but not at Langkawi, which is located closer to the magnetic dip equator. The results obtained from GNSS RO measurements revealed that daytime GHz scintillations observed at the two equatorial stations, UKM and Langkawi, were likely associated with blanketing sporadic (Esb).