國家太空中心研發的遙測衛星──福爾摩沙衛星五號上搭載的先進電離層探測儀（Advanced Ionospheric Payload，AIP），隨著不同的科學目的搭配各種次階量測模式，提供相關操作時間表和指令表……等，以達成科學需求。於2017年9月7日AIP進行了第一次量測，獲得第一次夜間軌道的電漿資料。在9月及10月的在軌測試後，於2017年11月開始例行操作穩定獲得科學資料，每兩日可獲得全球離子密度分布圖，而每四日就可獲得全球離子速度和離子溫度圖。取樣率採用1024Hz，儘可能取得最多的科學數據。AIP的初期量測中發現，衛星的電位比環境電漿的電位低上許多。為獲取可行的校正參數，因此與地面的Millstone Hill非同調散射雷達進行共同觀測，以確定AIP推導參數的可能偏差。而在電離層內偶爾能觀測到可能低於背景電漿密度的區域，此為電漿密度不規則體。統計電漿密度不規則體地區分布，計算其發生率，了解赤道區電漿密度不規則體隨季節的分布，並與過去文獻比對，可佐證福衛五號AIP的離子測量的正確性。

　　A remote sensing satellite, FORMOSAT-5, was developed by National Space Organization (NSPO) and carried a science payload, Advanced Ionospheric Payload (AIP). To reach the science requirement, AIP could operate by different measurement mode and provide the operating timeline to NSPO. The first AIP measurement was performed on 7 September 2017 and obtained the first-orbit data in the night-sight. After in-orbit checkout in September and October, AIP was routinely obtained the science data. The global ion density map was obtained every two days, and the global ion velocity and ion temperature were obtained every four days. AIP was operated by the sampling rate 1,024 samples per second and finalized to maximize useful science data. During the in-orbit checkout, it was found that the satellite has a much lower potential with respective to environmental plasma from measured current-voltage curves. In order to improve accuracy of the AIP measurement, co-incident observations have been scheduled with Millstone Hill incoherent scatter radar to identify possible bias on the derived AIP parameters. An area that might be lower than the background plasma density was occasionally observed in the ionosphere, which is the plasma density irregularities. Calculating the distribution of the plasma density irregularities and the occurrence rate could realize the seasonal variations of plasma density irregularities in the equatorial region. The result could compare with the past literature to prove the correctness of ion density measured by AIP.

Burke, W. J., C. Y. Huang, L. C. Gentile, and L. Bauer, Seasonal-longitudinal variability of equatorial plasma bubble occurrence, Ann. Geophys., 22, 3089-3098, 2004a.

Gentile, L. C., W. J. Burke, and F. J. Rich, A climatology of equatorial plasma bubbles from DMSP 1989–2004, Radio Sci., 41, RS5S21, doi:10.1029/2005RS003340, 2006.

Kelly, M. C., The Earth’s Ionosphere: Plasma Physics and Electrodynamics, Academic Press, Inc., 1989.

Ott, E., Theory of Rayleigh-Taylor bubbles in the equatorial ionosphere, J. Geophys. Res., 83, 2066, 1978.

Su, S.-Y., C. H. Liu, H. H. Ho, and C. K. Chao, Distribution characteristics of topside ionospheric density irregularities: Equatorial versus midlatitude regions, Journal of Geophysical Research: Space Physics, 111(A6), doi:10.1029/2005JA011330, a06305, 2006.

Su, S.-Y., C. K. Chao, and C. H. Liu, On monthly/seasonal/longitudinal variations of equatorial irregularity occurrences and their relationship with the postsunset vertical drift velocities, J. Geophys. Res., 113, A05307, doi:10.1029/2007JA012809, 2008.

Watanabe, S., and H. Oya., Occurrence characteristics of low latitude ionosphere irregularities observed by impedance probe on board the Hinotori satellite, Journal of Geomagnetism and Geoelectricity, 38(2), 125–149. doi:10.5636/jgg.38.125, 1986.

Wu, Q., Longitudinal and seasonal variation of the equatorial flux tube integrated Rayleigh-Taylor instability growth rate, Journal of Geophysical Research: Space Physics. doi:10.1002/2015ja021553-t, 2015.

林再文, 先進電離層探測儀, 國立中央大學, 博士論文, 2016.

FORMOSAT-5 Ground Segments Interface Control Document, FS5-ICD-0006.

SDC/AIP Data Website, http://sdc.ss.ncu.edu.tw/