AA Sa WEST SAP B Sae Mo E Oc d MEE EE“ A A FELT nk dde EEE AAN A enn UN A T clu a MEE 
Using these parameters, we get & spatial frequency fr which required 
for radiometer system. That is, 
benim Et Lite) 
OTF of optics at this spatial frequency is 0.51 (estimated from some 
measured data about a catoptric telescope). 
MTF of CCD array at the required spatial frequency for aperture 
pattern (1) (see Fig. 8) is 0.81, and for aperture pattern (2) is 0.60. 
These values can be calcurated by formula (3) and (4). 
From formula (2), 
2 — ZEN (1-6) Ta Un QTE) (MTF)aT (5) 
M 4 (S/N). (NES) 
When we are given the value for required signal ta noise ratio 
(S/N)a, can calcurate the required Fic of the optics. For some assumed 
(S/N)4 , the required Fyo are calcurated and the values shown with the 
required diameter of optics in Table UL. 
5. Conelusion 
We showed some results of conceptual design of electronic self- 
scanning radiometer. Required optics is such one that the speed is 
2, the aperture is about 150 mm, FOV is less than 6° and the focal 
length is about 300 mm. Such optics is realizable by either dioptric 
or catoptric system. Calibration of imaging data is rather difficult 
problem, because such electronic self-scanning system uses thousands 
of sensor elements and the spectral responses of these elements are 
not identical and differ eachother as shown in Fig. 6. Frequent onbcad 
calibrations will be impossible, and image construction might be done 
only by ground calibration data, therefore very high stability will 
be required for the senor element performances. Fortunately, CCD 
linear array is more stable than photomultiplier. 
Nevertheless, the utilization of such a linear array sensor seems 
to be a only probable solution to meet the requirement for higher 
resolution power in future remote sensing. 
13 
LIA dnd Sees, SF ER ME.