TDI scanning imaging system relative radiometric calibration method suitable for multichannel bidirectional output

Abstract

The invention belongs to the technical field of relative radiometric calibration and particularly relates to a TDI scanning imaging system relative radiometric calibration method suitable for multichannel bidirectional output. The method comprises the following steps: recording the maximum radiation brightness, recording brightness data at intervals, calculating multichannel average radiation response data, linearly segmenting collection points, performing two-point relative radiometric calibration for each segment, and recording the head-tail image average gray typical value of each segment, and selecting a corresponding relative radiometric calibration coefficient and other steps. Compared with the prior art, the method solves the problem of relative radiometric calibration of a multichannel TDI scanning imaging system, not only can control the relative radiometric calibration accuracy in a single channel, but also correct the inter-channel relative radiometric calibration precision.

Description

technical field [0001] The invention belongs to the technical field of relative radiometric calibration, in particular to a relative radiometric calibration method for a TDI scanning imaging system adapted to multi-channel bidirectional output. Background technique [0002] At present, optical remote sensing imaging systems are increasingly required to acquire large-width, high-signal-to-noise ratio target images in both military and civilian aspects. In order to obtain large-width, high signal-to-noise ratio target images, TDI scanning imaging is usually used. The TDI scanning imaging system mainly includes an optical system and a photodetector device. On the one hand, the optical system has vignetting, that is, the uniform target is transformed by the optical system to redistribute the energy, resulting in the concentration of energy at the center of the focal plane and gradually reducing to the edge, resulting in The energy distribution of the focal plane is not uniform; ...

AI Technical Summary

Problems solved by technology

The TDI scanning imaging system mainly includes an optical system and a photodetector device. On the one hand, there is vignetting in the optical system, that is, the uniform target is transformed by the optical system to redistribute the energy, resulting in the concentration of energy at the center of the focal plane and gradually decreasing to the edge, resulting in The energy distribution on the focal plane is uneven; on the other hand, due to the intrinsic characteristics of the material, the response characteristics of each detection pixel to the same energy input are different, resulting in uneven response; secondly, the data transfer rate of the TDI device is high, and the device often uses The multi-channel output structure meets the high-frequency data transfer, and the image produces channel block effect due to different channel signals passing through different paths and different operational amplifiers.

The inconsistency caused by the combined effects of these three factors will cause strong pattern noise in the acquired image, seriously affecting the imaging quality, and is an important and key factor restricting the multi-channel TDI scanning imaging system.

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