Lecture Notes
Updated Wednesday, 21-Jan-2004 09:52:06 EST

Remote Sensing

Electromagnetic Radiation from Warm Objects

 

(1 micron = 1 micrometer = 10-6 m.)

 Characteristic Spectrum of a Substance

Variation of Intensity with Distance

Instrument A is 10000 km from a warm object; instrument B is 30000 km away from the same object. Instrument A will receive 9 times greater intensity of radiated energy than instrument B.

Scanning

This is commonly called pushbroom scanning because the entire width of the swath is swept by the sensors at the same time. It requires somewhat simpler optics (lenses, etc.) but also requires a more complex and expensive multi-celled sensor.

This method is called side scanning since the pivoting mirror scans sideways across the swath. As with pushbroom scanning, the small sections on the ground can vary from less than a mile to several hundred miles. This method requires more complex optics (the pivoting mirror must be controlled by the computer very rapidly and precisely), but has the advantage of needing only one sensor.

 

Copyright © 1998, Robert G. Melton

Created 14-Mar-98
Updated Wednesday, 21-Jan-2004 09:52:06 EST