کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1765603 | 1020109 | 2009 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Application of HF Doppler measurements for the investigation of internal atmospheric waves in the ionosphere
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موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
علوم فضا و نجوم
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چکیده انگلیسی
We present results of the spectral analysis of data series of Doppler frequency shifted signals reflected from the ionosphere, using experimental data received at Kazan University, Russia. Spectra of variations with periods from 1Â min to 60Â days have been calculated and analyzed for different scales of periods. The power spectral density for spring and winter differs by a factor of 3-4. Local maxima of variation amplitude are detected, which are statistically significant. The periods of these amplitude increases range from 6 to 12Â min for winter, and from 24 to 48Â min for autumn. Properties of spectra for variations with the periods of 1-72Â h have been analyzed. The maximum of variation intensity for all seasons and frequencies corresponds to the period of 24Â h. Spectra of variations with periods from 3 to 60Â days have been calculated. The maxima periods of power spectral density have been detected by the MUSIC method for the high spectral resolution. The detected periods correspond to planetary wave periods. Analysis of spectra for days with different level of geomagnetic activity shows that the intensity of variations for days with a high level of geomagnetic activity is higher.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Advances in Space Research - Volume 44, Issue 6, 15 September 2009, Pages 685-692
Journal: Advances in Space Research - Volume 44, Issue 6, 15 September 2009, Pages 685-692
نویسندگان
I.R. Petrova, V.V. Bochkarev, R.R. Latipov,