Lijo Jose

GNU Radio Beacon Receiver (GRBR) observations of large-scale wave structure (LSWS) and equatorial spread F (ESF)

“GNU Radio Beacon Receiver (GRBR) is a new digital receiver based on GNU Radio and USRP (Universal Software Radio Peripheral) [Yamamoto, 2008]. In this paper, the GRBR observations of large-scale wave structure (LSWS) and the subsequent development of equatorial spread F (ESF) using total electron content (TEC) derived from the ground based reception of signals from the radio beacon on board C/NOFS (Communications/Navigation Outage Forecasting System) satellite are presented. The other evidences of LSWS include the ‘satellite traces’ observed in ionograms. These observations show that LSWS appears to play an important role in the development of ESF.

Planetary wave oscillations in the occurrence time of Equatorial Spread-F

This paper presents the role of planetary waves in modulating the occurrence time of Equatorial Spread F (ESF). The investigation has been carried out using the data from the digital Ionosonde and Proton Precession Magnetometer located over Trivandrum, India (8.5° E; 77° N; 0.5° N dip lat.). The analysis shows that the start-time of the ESF during the winter months is modulated significantly by a planetary wave of quasi-16-day periodicity. It is suggested that these waves are propagated to ionospheric altitudes from lower atmosphere through modified electrodynamics since the equatorial electrojet and pre-reversal enhancement were also showed the same oscillations.