Study on Nonlinear Process of Remote Sensing Camera Imaging at Visible Wavelengths

摘要

As the atmospheric environments get more complex, the surface characteristics are diverse, spaceborne remote sensing cameras with the characteristics of large aperture, long focal length, and small size are demanded ever-increasing, and the high-sensitivity photoelectric detectors are required to detect more observing targets, the nonlinear process of remote sensing imaging system is worth consideration. In this paper, time delay integrated charge-coupled device (TDICCD) is used as an example to analyze imaging chains of space remote sensing system at visible wavelengths. The nonlinear process influenced by atmospheric radiation transmission mode, the reflection characteristics of earth surface, ground-air couping effect, imaging optical system, TDICCD photoelectric detector, imaging electronics system, data transmission/compression system, and ground station system is researched in detail. At the same time, the method to reduce the nonlinear effects of the image is discussed. In order to apply the space remote sensing information to all walks of life effectively, the nonlinear process will be improved by high-precision atmospheric radiation transmission calculation, reducing the move of the image plane and the noise of the electronics system, designing the A/D converter with stable gain coefficient, optimizing the compression/decompression process, and reducing information loss of the remote sensing imaging system from satellite to the ground station system.