(19a) 
(19b) 
(19c) 
TW 
m} (19d) 
(19f) 
parameter 
) equations. 
(20a) 
(20b) 
(20c) 
(20d) 
(20e) 
(20f) 
or included 
(21a) 
(21b) 
(21c) 
(21d) 
  
  
  
  
  
SES | i gd (21e) 
[7 C 0 -s 
aw | CsSa 
o =(R+h) — CHC (211) 
C 
- - 0 
Iw S$sCa 
E =(R +h) $584 (21g) 
dn 
= CS 
3 i CsC4 
m sls (21h) 
|. | 
T SS 
  
The model parameters are assumed to satisfy the 
following conditions about the satellite attitude and 
position. 
Cond.(i) the satellite pointing is not deviated in 
amount of more than 12 degrees from the line between 
the satellite and the center of the Earth. 
Cond. (ii) the position of the satellite predicted from 
the orbital model allow only less than 2° error for the 
longitude and latitude and less than 30km error for the 
altitude of the actual position. 
If the deviated angle is 5, the Cond. (/) is described 
mathematically as 
    
    
    
  
> in sey sc) 
ö = tan” AR RISE ku Jecy vesc t ) ( s ) <12°.(22) 
Rain S2 
The Cond. (ii) is described mathematically as 
le — 6J < 2° 
In - n. <2 (23) 
| — ^| € 30km 
where do,no, and ho are expected parameters from the 
orbital model of the KITSAT-1. 
The model parameters are estimated repeatedly by using 
Eq.(17) with the conditions in the Eq.(22-23). The 
systematic correction based on the estimated parameter 
values was applied to remove the geometric distortions in 
the KITSAT-1 images. 
5. Result 
Following several pictures shows some geometrically 
corrected results of a wide angle camera image over the 
southern Europe, taken by the KITSAT-1 on May 8, 1995. 
Fig. 4 shows just a raw image. Fig. 5 shows the 
geometrically corrected image drawn in latitude and 
longitude grids. The model parameters to correct this 
image were estimated as 
61: -10.6551°, 02: 0.0361*, 03: 32.1341? 
¢: 28.3961°E, n: 40.9716°N, h: 1290.06Km 
The pointing error of the satellite at the time when this 
image was captured is calculated by using Eq.(22) and it 
is about 10.6552°. The corrected image is projected on 
the Mercator map in Fig. 6. The white lines on the figure 
are coast lines in a real map. 
  
Figure 6. An image over southern Europe of 
the KITSAT-1 
Figure 7. The preprocessed corrected image 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B3. Vienna 1996