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PHOTOGRAMMETRIC POTENTIAL OF JERS-1 OPS 
Torbjórn Westin 
SSC Satellitbild 
Box 816, S-98128 Kiruna, Sweden 
ISPRS Commission IV, WG2 
KEY WORDS: Satellite, DEM/DTM, Adjustment, Rectification, Accuracy, Stereoscopic, JERS-1 
ABSTRACT: 
The japanese JERS-1 is the first earth resource satellite to utilize the principle of along-track stereo. The optical 
VNIR instrument has four spectral bands based on CCD array sensors. Bands 1-3 (green, red and near-IR) are 
looking at nadir, while band 4 has the same spectral sensitivity as band 3 but is looking 15.33° forward. This 
gives the possibility for stereo images with B/H = 0.3. : 
To be able to use JERS-1 OPS for photogrammetric purposes, a model for interior and exterior orientation for 
JERS-1 OPS is developed. A least-squares adjustment procedure is developed for estimating the orbital and 
attitude parameters for strips of JERS-1 scenes. After adjustment, digital elevation models (DEM) are extracted 
by an existing software for multi-point least-squares matching. 
The photogrammetric capabilities of JERS-1 OPS using this system is evaluated in a case with six scenes 
acquired in a contiguous strip. The results of the tests show that a planimetric accuracy of 6 m rms error is 
possible, and that the stability allows us to reduce the number of control in the whole strip to only two points, 
without increasing the rms errors to more than 9 m. The result of the DEM extraction test shows that 20 m rms 
error in elevation is possible. It also shows that this accuracy can be achieved without any control at all in the 
stereo pair, by only using control points further away in the strip. 
1. INTRODUCTION 
The launch of JERS-1 in 1992 gave us new tools in 
optical remote sensing. The problems and A 
discontinuation of the middle infrared bands in 1993 1 
was unfortunate, but still the VNIR bands is a good x 
source of data, . Also, its along-track stereo possibility 
is unique. The optical VNIR instrument has four 
spectral bands based on CCD array sensors. Bands 
1-3 (green, red and near-IR) are looking at nadir, 
while band 4 has the same spectral sensitivity as S/C DIRECTION 
band 3 but is looking 15.33? forward (Figure 1). This Ca 
gives the possibility for stereo images with B/H = 0.3. 
The nominal pixelsize is 18 m across-track and 24 m 
along-track. 
   
GROUND 
C 7 
The purpose of this study is to investigate the f ( 7 Y S es 
potential photogrammetric capabilities of JERS-1, in Sadi m 
terms of geometric accuracy both in planimetry and 
altimetry. Pursuing high geometric accuracy is very 
important in many respects, not only in cartographic Figure 1. Imaging geometry of the JERS-1 VNIR 
applications. Change detection and other instrument (reproduced from NASDA, 1990). 
multitemporal studies often require better than half 
pixel accuracy to give good results. So do also multi- — An other very important aspect investigated is the 
sensor studies, such as merging VNIR data with = stability of the photogrammetric model, ie. if it is 
SPOT Pan or with SAR data. possible to achieve high geometric accuracy with only 
  
  
  
  
937 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996