Multi-wavelength (L and S band) study of ionospheric irregularities from an anomaly crest location

During current solar cycle 25, these occurrences are probably being reported for the first time, from a low-latitude station Calcutta (22.58 DEG;N, 88.38 DEG;E geographic; magnetic dip 34.54 DEG;), located near the northern crest of Equatorial Ionization Anomaly. Efforts have been made to analyze irregularity dynamics at IRNSS S band, along with a comparative study at GNSS L1 to characterize occurrence and evolution of multiscale irregularity structures.

Power spectral analysis technique has been applied on recorded C/N-O,N- during scintillation patches, to measure east-west zonal drift velocity. Efforts are also made to study intensity of signal perturbation at L5 frequency of IRNSS, compared to S band, when observed simultaneously, during period of ionospheric scintillation. Concurrent irregularity dynamics at L1, L5, and S band, particularly from a low-latitude station, has not been extensively reported earlier.