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Read Full Article (file size: 524542 bytes) Cited by
JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 109,
A07308,
doi:10.1029/2004JA010396,
2004
A statistical study of subauroral E-region coherent backscatter observed near 100 MHz with passive radar
Melissa G. Meyer
Department of Electrical Engineering, University of Washington, Seattle, Washington, USA
John D. Sahr
Department of Electrical Engineering, University of Washington, Seattle, Washington, USA
Andrew Morabito
Department of Electrical Engineering, University of Washington, Seattle, Washington, USA
Abstract
We provide a statistical summary of the Doppler features extracted from 21,000 independent E-region irregularity observations
made during 2002 and 2003. These data were acquired using the Manastash Ridge Radar, which detects the scatter of commercial
FM broadcasts near 100 MHz and observes at subauroral latitude. In particular, we present histograms of Doppler velocity and
spectral width of the observations and discuss trends in these data with respect to local time and the geomagnetic Kp index. We find an asymmetric velocity distribution composed entirely of type 1 Doppler spectra; these waves are associated
with the modified two-stream instability. Type 2 echoes are completely absent, suggesting a strong latitude and/or wave number
dependence in the conditions for secondary wave instability. We compare our observations with HF and VHF coherent scatter
results reported by others. Because the radar is completely passive, it is well suited for extended, unattended observations;
in this 2-year period of nearly continuous operation, we find pronounced seasonal variation in our observations. The method
of radar operation provides excellent data for statistical summary, as it is completely free of range and Doppler aliasing,
while also providing fine time and frequency resolution.
Received 21
January
2004;
accepted 17
June
2004;
published 27
July
2004.
Keywords: ionosphere;
irregularities;
radar.
Index Terms: 2439 Ionosphere: Ionospheric irregularities; 2443 Ionosphere: Midlatitude ionosphere; 6969 Radio Science: Remote sensing; 0910 Exploration Geophysics: Data processing.
Read Full Article (file size: 524542 bytes) Cited by
Citation: Meyer, M. G., J. D. Sahr, and A. Morabito
(2004),
A statistical study of subauroral E-region coherent backscatter observed near 100 MHz with passive radar,
J. Geophys. Res.,
109,
A07308,
doi:10.1029/2004JA010396.
Copyright 2004 by the American Geophysical Union.
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