Multi-source Data Assisted Radiometric Calibration Of Optical Remote Sensing Image

Multi-source remote sensing data processing and application technology is not only an effective means of resource and environment information detection,but also the first choice for monitoring of ecological environment changes.In the agriculture,forestry,hydrology and mapping industries,there is a huge demand for the processing and application of multi-source remote sensing data.The combination of multi-source remote sensing data will greatly improve the productivity of these industries.In recent years,domestic satellite construction has been advancing rapidly,and multi-spectral,hyperspectral and full-color remote sensing data have been applied in many fields.The radiation correction quality of these data has a significant impact on the application of related industries.Effective radiation correction will play a fundamental role in the follow-up data application.The main contents of this paper are divided into the following two parts:First,the ground and aerial remote sensing data assisted by the optical remote sensing satellite image radiation correction.Field radiometric calibration requires the test site of uniform features and stable reflectivity,so mixture of objects and spectral mixing will lead to poor radiation calibration quality when test site is not suitable for use.For non-field radiometric calibration,only the use of ground control points to measure the spectrum is clearly not a comprehensive reflection of the real situation.Considering the presence of surface-point difference between satellite imagery and measuring point,and the difficult of multi-source remote sensing data fusion,this paper proposes a radiation correction method using aerial imagery as a transition between ground measurement and satellite observation.Experiments use Specim Aisa Eaglet airborne hyperspectral imager to capture Jiangsu province Changshu district,synchronous collect ground ASD data and get the image of GF-1 and HJ-1.use ground measurement to calibrate aerial imagery firstly,and then unite calibrated aerial imagery with 6S atmospheric transportation model to calibrate satellite imagery.Experimental results and accuracy verification show that the calibration method is more effective and more accurate than the conventional method of directly correcting satellite imagery with ground data.Compare the two satellite calibration results using the same method,GF-1 satellite is superior to HJ-1 satellite.The effect of the aerial image as a transition,wavelength integral and spatial synthesis in the radiation correction method is remarkable and can be studied further and utilized effectively.Second,Radiometric correction of optical remote sensing satellite images based on spaceborne remote sensing data includes multispectral image correction and hyperspectral image correction.During the radiometric correction of optical remote sensing satellite images,which are assisted by spaceborne data,first,DN of the corresponding region is gained according to the control-point information.Second,we calculate radiance using the DN of the calibrated image.Radiance of the undetermined image is calculated based on the channel matching factors and radiance of the calibrated image.Then,the calibration coefficients are obtained by fitting the radiance with the DN of the undetermined image by least squares.Finally,we can get the corrected reflectance image according to the calibration coefficients of radiance and ground reflectance.During the radiation correction of Hyperspectral image aided by spaceborne data,considering hyperspectral data which cover short wave infrared(2.1nm),blue band(0.47nm),the red band(0.66nm),we correct the hyperspectral remote sensing data by using dark target iterative method.In the method,atmospheric parameter lookup is constructed by the 6S radiation transmission model.Taking Wuhan city as the research area,the atmospheric correction is carried out with Hyperion hyperspectral data as the data source.