HF Doppler radar observations of sporadic E at an Indian low latitude station, Visakhapatnam

Multi-frequency observations of E-region HF radar aurora

Multi-frequency observations of E-region coherent backscatter from decametre waves reveal that auroral echoes tend to comprise two spectral components superimposed, one at low Doppler shifts, below 250 m s−1, and the other Doppler shifted to near the ion-acoustic speed or above, up to 800 m s−1. The low Doppler shift component occurs at all look directions; Doppler shifts near the ion acoustic ...

Simultaneous VHF radar backscatter and ionosonde observations of low-latitude E region

The first results of simultaneous observations made on the low-latitude field-aligned irregularities (FAI) using the MST radar located at Gadanki (13.5 N, 79.2 E, dip 12.5) and the Es parameters using an ionosonde at a nearby station Sriharikota (13.7 N, 80.1 E, dip 12.6) are presented. The observations show that while the height of the most intense radar echoes is below the virtual height of E...

Doppler Radar Observations

High-latitude HF Doppler observations of ULF waves. 1. Waves with large spatial scale sizes

A quantitative study of observations of the ionospheric signatures of magnetospheric ultra low frequency (ULF) waves by a high-latitude (geographic: 69.6°N 19.2°E) high-frequency Doppler sounder has been undertaken. The signatures, which are clearly correlated with pulsations in ground magnetometer data, exhibit periods in the range 100±400 s and have azimuthal wave numbers in the range 3±8. Th...

High-latitude HF Doppler observations of ULF waves: 2. Waves with small spatial scale sizes

The DOPE (Doppler Pulsation Experiment) HF Doppler sounder located near Tromsù, Norway (geographic: 69.6°N 19.2°E; L = 6.3) is deployed to observe signatures, in the high-latitude ionosphere, of magnetospheric ULF waves. A type of wave has been identi®ed which exhibits no simultaneous ground magnetic signature. They can be subdivided into two classes which occur in the dawn and dusk local time ...