Simultaneous 1.5‐ and 4‐GHz ionospheric scintillation measurement

Abstract

Analysis of simultaneously recorded 1.5‐ and 4‐GHz scintillations at Tangua, Brazil, has shown that the scintillation index varies approximately as the wavelength between 1.5 and 4 GHz under weak scattering conditions. The amplitude distributions, especially those of the 1.5‐GHz data, are somewhat irregular in shape and cannot be represented by a simple mathematical expression. The power spectra of the amplitude fluctuations on a log‐log plot show a slope of −3 and have low wave number rolloffs near 10−2 m−1. This paper discusses some possible implications of these findings. Half of the 4‐GHz power spectra show the minima which are predicted by the thin‐screen weak scattering theory. The l/e falloff of the autocorrelation corresponds to irregularities between 100 and 200 m. The cross correlation between the 1.5‐ and 4‐GHz scintillations is about 0.3.

Model computations of radio wave scintillation caused by equatorial ionospheric bubbles

“…Saturation becomes the dominant factor for strong scintillation cases. This frequency dependence is consistent with the observational data [Taur, 1976]. Thus by using the models for the bubble developed from in situ data and simulation results, we have shown that scintillation patterns similar to those observed experimentally are obtained when radio waves propagate through those bubbles.…”

Space Weather: Historical and Contemporary Perspectives

“…The ionosphere was found by the COMSAT engineer Taur (1973Taur ( , 1976 to disturb even the GHz frequencies used for satellite-to-ground signals. The scintillation of these signals has proven to be a significant impediment to communications and navigation, especially in the equatorial and auroral regions (e.g., Basu and Basu 1981).…”

Aperture Antenna Effects After Propagation through Strongly Disturbed Random Media

“…a propagating wave is oftenobservedi over satellite, links at VHF and 1JHF . Scin~tillation can' also be observed at frequencies as high as the-Gilz range (Pope and Fritz, 1971;Skinner et al, t971;Taur. 1976) 2nd is occasionally si~ver'e, oven at L-band (Frernouw et al, 1978).…”