• Multi-frequency HF radar measurements of artificial F-region field-aligned irregularities. 

      Rietveld, Michael T.; Senior, A.; Borisov, N.D.; Kosch, M.J.; Yeoman, T.K.; Honary, F. (Journal article; Peer reviewed; Tidsskriftartikkel, 2004-11-03)
      We present radar backscatter power measurements using the CUTLASS HF radar at Hankasalmi, Finland from F-region field-aligned irregularities induced by HF radio pumping with the EISCAT Heating facility. A novel radar operating mode is used in which the radar frequency is rapidly swept through a number of bands, making use of the varying ionospheric refraction to probe different heights within the ...
    • Observations of plasma density structures in association with the passage of traveling convection vortices and the occurrence of large plasma jets. 

      Van Eyken, A.P.; Valladares, C.E.; Alcaydé, D.; Rodriguez, J.V.; Ruohoniemi, J.M. (Journal article; Peer reviewed; Tidsskriftartikkel, 1999)
      We report important results of the first campaign specially designed to observe the formation and the initial convection of polar cap patches. The principal instrumentation used in the experiments comprised the EISCAT, the Sondrestrom, and the Super DARN network of radars. The experiment was conducted on February 18, 1996 and was complemented with additional sensors such as the Greenland chain of ...
    • Probing of medium-scale traveling ionospheric disturbances using HF-induced scatter targets 

      Rietveld, Michael T.; Blagoveshchenskaya, N. F.; Borisova, T. D.; Kornienko, V. A.; Moskvin, I. V.; Frolov, V. L.; Uryadov, V. P.; Kagan, L. M.; Yampolski, Yu. M.; Galushko, V. L.; Koloskov, A. V.; Kasheev, S. B.; Zalizovski, A. V.; Vertogradov, G. G.; Vertogradov, V. G.; Kelley, M. C. (Journal article; Tidsskriftartikkel; Peer reviewed, 2006-09-20)
      Experimental results from the Tromsø and Sura heating experiments at high and mid-latitudes are examined. It is shown that the combination of HF-induced target and bi-static HF Doppler radio scatter observations is a profitable method for probing medium-scale traveling ionospheric disturbances (TIDs) at high and mid-latitudes. HF ionospheric modification experiments provide a way of producing ...
    • The relationship between small-scale and large-scale ionospheric electron density irregularities generated by powerful HF electromagnetic waves at high latitudes 

      Tereshcenko, E.D.; Rietveld, Michael T.; Brekke, Asgeir; Khudukon, B.Z.; Isham, B.; Hagfors, T. (Journal article; Peer reviewed; Tidsskriftartikkel, 2006-11-21)
      Satellite radio beacons were used in June 2001 to probe the ionosphere modified by a radio beam produced by the EISCAT high-power, high-frequency (HF) transmitter located near Tromsø (Norway). Amplitude scintillations and variations of the phase of 150- and 400-MHz signals from Russian navigational satellites passing over the modified region were observed at three receiver sites. In several papers ...
    • Statistical signature of active D-region HF heating in IRIS riometer data from 1994–2004 

      Rietveld, Michael T.; Kero, A.; Enell, C.-F.; Ulich, Th.; Turunen, E.; Honary, F. H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2007-03-08)
      In this paper we study the effect of artificial HF heating on cosmic radio noise absorption in the D-region ionosphere. The effect has earlier been studied theoretically in idealised cases and without experimental verification. Here we present a 3-dimensional modelling of the effect, taking into account the directivity patterns of the vertical beam of the EISCAT Heater at Tromsø, Norway, and ...
    • Stimulated Brillouin scattering during electron gyro-harmonic heating at EISCAT 

      Fu, Haiyang; Scales, Wayne A.; Bernhardt, Paul A.; Briczinski, Stan J.; Kosch, Michael J.; Senior, Andrew; Rietveld, Michael T; Yeoman, Timothy Kenneth; Ruohoniemi, J. Michael (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-11)
      Observations of secondary radiation, stimulated electromagnetic emission (SEE), produced during ionospheric modification experiments using ground-based, high-power, high-frequency (HF) radio waves are considered. The High Frequency Active Auroral Research Program (HAARP) facility is capable of generating narrowband SEE in the form of stimulated Brillouin scatter (SBS) and stimulated ion Bernstein ...