PERFORMANCE PREDICTION OF AVNIR BY A SIMULATOR 
HAJIME KOSHIISHI 
Remote Sensing Technology Center 
7-15-17, Roppongi, Minatoku, Tokyo, Japan 
MASAO NAKA 
National Aerospace Laboratoly 
YOSHIYUKI KAWATA 
Kanazawa Technology Institute 
YOSHITAKA IWATA 
Fujitu F.I.P Co.Ltd 
CC ISPRS Commission II, Working Group 2 
.yse 
[ues ; : ; 
t à KEY WORDS: Imaging spectrometer, Pushbroom scan, Simulation, ADEOS, AVNIR 
de 
iute 
des ABSTRACT 
des 
les. The AVNIR(Advanced Visible Near Infrared Radiometer) is one of core sensors of japanese 
next earth observation satellite ADEOS. The AVNIR has linear array for each multi- 
spectral band and panchromatic band, and uses the pushbroom scheme for scanning. The 
pushbroom scan has a sampling process in cross track scan as the inherent property. In 
along track scan, there is no such a inherent sampling process, but there will be a image 
phy degradation by the satellite motion. In such a high resolution spectrometer, the atmospher 
stam has significant effect on the spatial resolution. A digital simulator for performance 
-ing analysis and design of imaging spectrometer was developed. The performances of AVNIR 
Pert affected by such a sampling process, degradations by satellite motion and atmosphere were 
les. studied by the simulator and the results are presented. 
and 
the 
or 1. INTRODUCTION electron charge of each sensor element co- 
rresponds to radiance is scanned electro- 
Recent high resolution imaging spectrometer nically. Therefore, here is a sampling 
, such as HRV of SPOT, OPS of JERS-1, and process inherently. Aliasing ploblem will 
MESSR of M0S-1, has a linear array on the be in such a pushbroom scan system. For 
focal plane for each spectral band, and reduction the aliasing, it is necessary to 
uses pushbroom scheme in the cross track increase the number of sensor element and 
scan. The linear array includes a lot of to cut the higher excessive frequency res- 
sensor elements, for example, 6,000 ele- ponce. 
ments for HRV and 4,000 elements for OPS. In the along track scan, there is no such a 
The linear array is put on the focal plane alias problem, but the imaging data is de- 
of optics in cross track direction, and the graded by the motion of platform. 
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