首先的工作就是模擬出高解析力的衛星影像，這張影像必須是要考慮地表的地形變化、人工建築物的存在和相互的遮蔽問題。模擬衛星影像的程序是利用已經建構好之ROCSAT-2的軌道參數、星曆資料和DSM(Digital Surface Model)以逆轉換模式（Bottom-up）來進行模擬，而模擬影像所要填入的灰度值資訊則是利用經正射、鑲嵌後之數位航空影像來當基準，如此一來模擬的衛星影像才會和真實影像相近。
在模擬衛星影像的工作完成後，接下來就是要進行正射化的工作，在此階段中，利用已經建構好的ROCSAT-2的軌道參數、星曆資料和DSM以逆轉換模式來進行正射化的程序。在完成正射化程序後的衛星影像，將可以修正在衛星影像上因為高差移位效應所呈現之傾斜人工建築物及地形至正確的影像位置上。

First of all, we used a satellite-orbit-model of ROCSAT-2, including coordinate-transformation-model, satellite-fly-model, simulation-model and on-board-data-model, and DSM to simulate a high resolution satellite images by Bottom-up approach. In addition, the bases of the simulated image are orthorectified aerial images to minimize differences between the simulate image and the true image.
Once imaging simulation had completed, we will use a satellite-orbit-model of ROCSAT-2 and DSM to orthorectify the simulated high resolution satellite''s image by Bottom-up.

1.Ackermenn, F. (1984), “Digital Image Correlation: Performance and Potential Application in Photogrammetry.” Photogrammetric Record, 11(64): 429-439.
2.Chen, L. C., and Lee, L.-H. (1993). “Rigorous Generation of Digital Orthophotos from SPOT Images.” Photogrammetric Engrg, And Remote Sensing, 59(5), 655-611.
3.Chen, L. C., and Chang, L.Y., (1998), “Tree Dimensional Positioning Using SPOT Stereostrips with Sparse Control.” Journal of Surveying, ASCE 124(2): 63-72.
4.Chen, L.C., and Wu, Y.Y., 2000, “Image Geometric Simulation and Orientation Modeling for ROCSAT-2”, Proceedings of the 21st ACRS, in press.
5.Chen, L. C., and Rau, J. Y., (1993), “A Unified Solution for Digital Terrain Model and Orthoimage Generation from SPOT Stereopairs.” IEEE Transacrtions on Geoscience and Remote Sensing, 14(16):1243-1252.
6.Fritz, L. W., 1999, “High Resolution Commercial Remote Sensing Satellites and Spatial Information Systems. ”, Highlights of ISPRS, vol. 4, no. 2, pp. 19-30.
7.Gugan, D. J., and Downman, I. J., (1988), “Accuracy and Completeness of Topographic mapping from SPOT Imagery.” Photogrammetric Record, 12(72), 787-796.
8.Gugan, D. J. , and Downman, I. J., (1988), “Accuracy and Completeness of Topographic mapping from SPOT Imagery. ” Photogrammetric Record, 12(72), pp.787-796.
9.Gerald, C. F., and Wheatley, P. O., 1994, “Aplied Numerical Analysis. ”, Addison-Wesley Publishing Co., Reading, Mass.
10.Konecny, G., Kruck, E., Lohmann, P., and Engel, H., (1987), “Evaliation of SPOT Imagery on Analytical Photogrammetric Instruments.” Photogrammetric Engrg. and Temote Sensing, 53(6),1223-1230.
11.Lee, L.-H., (1991), “A Conputational Vision /approach ot Geometrical Analysis for SPOT Images.” PhD Thesis, Inst. of Atmospheeric Physicsm National Central University, Chung-Li, Taiwan.
12.Mayr, W., and Heipke, C., (1988), “A Contribution to Digital Orthophoto Generation.” Int, Archives of Photogrammetry and Remote Sensing, Kyoto, Japan, 27(B11), IV430-$39.
13.Mikhail, E. M. and F. Ackermann, 1982, “Observation and Least Squares. ”, University Press of America, New York, pp.393-426.
14.Rau, J.Y., and Chen, L.C., 1999, “Digital Orthoimage Generation from Large Scale Aerial Photography”, Proceedings of 20th ACRS, pp.707-712.
15.Westin, T., (1990), “Precision Rectification of SPOT Imagery.” Photogrammetric Engeg. and Remote Sensing, 56(2),247-253.
16.Wiesel, J. W., (1985), “Digital Image Processing for Orthophoto Generation.” Photogrammetria, 40(2), 69-76.
17.吳怡瑛，2000，“中華二號衛星影像幾何模擬及方位重建”，碩士論文，國立中央大學土木工程研究所。
18.張立雨，1995，“SPOT衛星載體參數應用於物空間三維定位與影像正射化之研究”，碩士論文，國立中央大學太空科學研究所。
19.李良輝，1993，“遙測影像之三維地形景觀視覺” 中山科學研究院研究報告，中正理工學院測繪工程學系，pp.7-9，125-126。
20.曾清涼，1990，”公分級精度(GPS)測量(II)”，國科會研究報告， NSC78-0410-E006-30，國立成功大學測量工程系，p.151。
21.許才仁，1996 “應用局部過濾及邊緣線對應改善數化空照立體對之區域匹配”，碩士論文，國立中央大學土木工程研究所，61 pages。
22.陳良健，2000，“ROCSAT-2衛星影像幾何校正前處理運算法則之建立”，國科會研究報告，NSC88-NSPO(A)-PC-FA07-01，國立中央大學太空及遙測研究中心，pp.2-22。
23.饒見有，陳良健，1996，“紋理分析於SPOT立體像對影像匹配動態視窗之應用”，第十五屆測量學術及應用研討會論文集，政治大學，pp.717-725。
24.曾忠一，1983，“大氣遙測原理與應用”，台北，pp.8-22。
25.太空計畫室網站，2001，www.nspo.gov.tw。