Study On The Information Acquisition Technology Of Infrared FPA TDI Detection System

There are currently increasingly demands of image system spatial and temporal resolution and sensitivity on space remote sensing applications.Time delay integration technique could improve the detect sensitivity under the condition of making no influence on system spatial and temporal resolution,and hence it has been widely used on space remote sensing.With the development of infrared focal plane array,windowing technique make it possible for array detector to realize digital TDI.This paper studied digital TDI technique based on infrared array detector.Then it also analysed the influence factor of digital TDI on system spatial and temporal noise and the influence of high frame rate detect on digital TDI image system.The main research contents are as follows:1) Analysed the noise sources of the image system and established system noise model as well as discussed and simulated the improvement effect of TDI on signals that contain different types of noise.2) Analysed the influence factor of TDI on SNR improvement effect.Define the deviation that actual value and theoretical value of SNR improvement so as to quantify the SNR improvement effect.At the condition of 40 TDI stages,the deviation is up to 10%. At the condition of 20 TDI stages,the SCR is up from 6.9 to 10.2.3) Established the spatial noise model based on the non-uniformity sources of focal plane array and studied the influence of TDI on system non-uniformity with this model, separated by rows and columns. At the condition of 64 TDI stages,the non-uniformity of row is from 5.76% down to 0.019%,and the non-uniformity of column is from 6.545% down to1.09%.4) Analysed the influence of windowing high frame rate on TDI image system from three aspects:the scan velocity,system velocity matching as well as the realization of upper computer digital TDI. And then discussed the digital TDI realization with upper computer and high frame rate image data.5) Established the infrared scaning image system and did experiments with this image system.Made test of spatial and temporal noise as well as the array detector non-uniformity.Analysed the influence of TDI on point target detection.Realized upper computer digital TDI with high frame rate data and the result verified the influence of windowing high frame rate detection on TDI image system.