4 and S/N of VTIR hardware measured in the factory was larger in 
band 3 than in band 4. 
(3)Geometric distortion compensation evaluation 
By using 20 GCPs in one pass scene, position error of level 2 
imagery was measured to be 3.1-4.7km which is under specified 
value 7 pixels (6.3 km). 
(4)Spatial resolution evaluation 
By using edge of coast, spatial resolution was measured as 
follows: 
line direction pixel direction 
Band 1 1.4 pixel 3.3 pixel 
Band 3 3.0 pixel 4,8 pixel 
Band 4 3.3 pixel 5.4 pixel 1 pixel:900m 
In case of band 2, spatial resolution can not be obtained because 
earth surface can not be observed, Concerning thermal band ( 
Band 2,3,4),three pixel is nominal spatial resolution. 
(5)Sea surface temperature extraction evaluation 
LOWTRAN 6 was applied to VTIR thermal band  imagery(Path 
21,May 31,1987) and the following results were obtained. 
  
  
  
level 2 Atmospheric compensated | Truth 
data data data 
Band 3 Band H Band 3 Band 4 
17.85 16.40 19.65 18.85 19.6 (Omaezaki) 
18.00 16.35 20.50 19.35 19.2 (Oshima) 
  
  
  
  
Remark: Radio sonde data was used. unit: °C 
3.3 MSR 
The MSR is a Dicke type radiometer to measure very weak earth 
radiation noise at the 23 GHz and 31 GHz. Beam width of MSR is 
32 km (23 GHz) and 23 km (31 GHz). Main nission objective of the 
MSR is to measure water vapor and liquid water, snow cover, sea 
ice distribution. 
(1)Radiometric distortion compensation evaluation 
By measuring mean and standard deviation in level 2 imagery, 
the following results were obtained. 
23 GHz 10msec 1.14 K 
23 GHz 47msec 1.43 K 
31 GHz 10msec 1.33 K 
31 GHz 47msec 1.30 K 
In ease of evaluation of internal calibration source, the 
102