| 研究生: |
張喻翔 Yu-Hsiang Chang |
|---|---|
| 論文名稱: |
利用中壢特高頻雷達觀測散塊E層及150公里處不規則體之特性分析 Observation of Es and analysis of irregularity in 150 km by using Chung-Li VHF radar |
| 指導教授: |
朱延祥
Yen-Hsyang Chu |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
地球科學學院 - 太空科學研究所 Graduate Institute of Space Science |
| 畢業學年度: | 98 |
| 語文別: | 中文 |
| 論文頁數: | 129 |
| 中文關鍵詞: | 特高頻雷達 、散塊E層 、150公里處不規則體 |
| 外文關鍵詞: | sporadic E, 150 km, radar, VHF |
| 相關次數: | 點閱:9 下載:0 |
| 分享至: |
| 查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報 |
利用中壢特高頻雷達站52MHz天線於2009年7月19日夜間觀測得一筆位於150公里處的不規則體回波。經過各種分析方式表達其位於150公里處不規則體相對於雷達站的都普勒速度、頻譜寬、追蹤速度及雷達干涉法定位出來的三維結構與典型的散塊E層及與2008年2月5日所觀測得的一筆F層的回波訊號比較下,發現於150公里附近的不規則體其頻譜特性、追蹤速度與三維結構具有獨特性。因此150公里不規則體其回波特性及物理機制應獨立討論。
利用崙坪電離層觀測站所觀測得的電離圖與中壢特高頻雷達站的回波訊號,比較其兩者高度之間具有一定的相關性,證明在150公里處的回波為確實存在的;厚度與頻譜寬的比較有一定的相關程度,代表當電離圖觀測的厚度越厚則其內部的電漿運動越複雜,所以收到的回波訊號頻譜寬越寬;而電離圖所觀測得的臨界頻率與電子密度成正比,所以與特高頻雷達所觀測得的回波強度應有一定的相關性。
The Chung-Li VHF radar had observed echoes of 150 km irregularities during nighttime of 2009/07/19 .After analyzing Doppler velocity、spectrum width、trace velocity and three dimensional echo location by radar interferometry which in 150 km height, and comparing to sporadic E and F region observed during 2008/02/05 could know that the spectrum characteristics、trace velocity and echo location of 150 km irregularities has uniqueness. The mechanism of 150 km should be discussed independently.
Comparing the Ionogram which observed by Lun-Ping ionosonde station with echoes which observed by Chung-Li VHF radar, the correlation coefficient is highly trustworthy. It means the irregularities existed definitely in 150 km. The thickness of Ionogram is dependent to the spectrum width observed by VHF radar. The critical frequency observed by Ionogram is also proportional to electron density may have dependence between the echo power observed by VHF radar .
Balsley, B. B., Some characteristics of non-two-stream irregularities in
the equatorial electrojet, J. Geophys. Res., 74, 2333-2347, 1969.
E. R. de Paula, D. L. Hysell, The Sao Luis 30MHz coherent scatter ionospheric radar: System description and initial results, Radio Sci., 39, 1014-1029 ,2004
Farley, D. T., A plasma instabilities resulting in Field-aligned
irregularities in the ionosphere, J. Geophys. Res., 68, 6083-6097, 1963.
Farley, D.T., H. M. Ierkie, and B. G. Fejer, Radar Interferometry, J.
Geophys. Res., 86, 1467-1472, 1981.
Fejer, B. G., D. T. Farley, B. B. Balsley, and R. F. Woodman, Vertical
structure of the VHF backscattering region in the equatorial electrojet and
the gradient drift instability, J. Geophys. Res., 80, 1313-1324, 1975.
Fejer,B.G., J.Providakes, and D.T. Farley, Theory of plasma waves in the auroral E region, J. Geophys. Res., 89, 7487-7494, 1984.
Kato, S., Diurnal atmospheric oscillation. 1.Eigenvalues and Hough
Functions; 2. Thermal excitation in the upper atmosphere, J. Geophys.
Res., 71, 3201-3209, 3211-3214,1966.
Kelley, M. C., The Earth’s Ionosphere: Plasma Physics and
Electrodynamics, 487pp., Academic, San Diego, Calif., 1989.
Kudeki, E., and C. D. Fawcett, High resolution observations of 150 km echoes at Jicarmarca, Geophys. Res., 105, 5317.
Nygren T., L. Jalonen, J. Oksman and T. Turunen, The role of electric
field and neutral wind dtrection in the formation of sporadic E-layers, J.
Atmos. Terr. Phys., 46, 373-381, 1984.
Riggin D., W. E. Swartz, J. Providakes, and D. T. Farly Radar studies of
long-wavelength waves associated with mid-latitude sporadic E layers, J.
Geophys. Res., 91, 8011-8024, 1986.
Sudan, R. N., J. Akinrimisi and D. T. Farly, Generation of small-scale
irregularities in the equatorial electrojet, J. Geophys. Res., 78, 240-248,
1973.
Tanaka, T., and S. V. Venkateswaran, Characteristics of field-aligned
E-region irregularities over Ioka (36o ), Japan, I. J. Atmos. Terr. Phys., 44,
381-394, 1982.
Tsunoda, R. T., Enhanced velocities and a shear in daytime Esq over Kwajalein and their relationship to 150 km echoes over the dip equator, Geophys. Res. Lett., 27, 657.
王建亞, 利用中壢VHF 雷達進行電離層散塊E 層不規則體之觀測, 國立中央大學太空科學研究所, 博士論文, 1999.
陳祥章, 中壢雷達三維輻射場型模擬與分析及系統建立, 國立中央大學太空科學研究所, 碩士論文, 2005.
楊國峰, 電離層散塊 E 層不規則體結構與特性之研究, 國立中央大學太空科學研究所, 博士論文, 2008.