Correction of influence of alternating voltage coupling in a signal chain of scanning opto-electronic sensors

摘要

A method for correction of influence of alternating voltage coupling in a signal chain of scanning opto-electronic sensors on radiometric data thereof is carried out by firstly ascertaining, and storing, characteristic times from the time constant of a RC-circuit of the signal chain of the respective spectral channel, a line scanning frequency and a number of image elements per scanline. A preliminary correction in the form of a recursive inverse RC-filtering of the sampling values is then performed for each image element of a channel with its characteristic time, and the preliminary corrected image data are intermediately stored channel-by-channel and line-by-line. In the case of the use of a dark reference source completely independent of external radiation, corrected pixel values are computed immediately and directly on the basis of the preliminarily corrected and intermediately stored image data with the aid of dark reference signals present at the sensor output for each channel.