فهرس المقالات radiometric calibration

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  1 - Selecting Remotely Sensed Images Radiometric Calibration Site (Case Study: Tehran Province)
  Mohammad Javad Khodam Abbas Bashiri Hasan Hasani Moghaddam Seyyed Mohammad Afghahi Hasan Tabarsi
  Radiometric errors are the most common errors of data acquired by remote sensing sensors. Correction of this type of error requires knowledge about the atmospheric conditions during imaging of the sensor. The aim of this study is to select an ideal location for the cons أکثر

  Radiometric errors are the most common errors of data acquired by remote sensing sensors. Correction of this type of error requires knowledge about the atmospheric conditions during imaging of the sensor. The aim of this study is to select an ideal location for the construction of a radiometric calibration site. Tehran province was selected as a case study to conduct research in a pilot environment. Based on the studies performed on the CEOS standards in site selection as well as the criteria observed in Cal Val sites, 14 parameters were selected as important and necessary parameters for calibration site selection. The data used in this research include two categories of satellite data and GIS layers. After applying the preprocessing on the data and obtaining the weight of each layers, suitable places were obtained for the construction of the calibration site between 2012 to 2019 years. Due to the importance of the consistency of the selected place during different years, the places that were always suitable between the evaluated years, were selected. The results of the research show an ideal location in the western region of Tehran for site construction, which has been selected very well suitable in terms of all criteria. In addition to developing the appropriate location for the calibration site uses, instruments such as san-photometer and goniometer were also developed to be installed on the site to provide services to multispectral and hyperspectral sensors. تفاصيل المقالة
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  2 - A novel method for Sentinel-2 satellite images radiometric calibration
  Abbas Bashiri Hasan Hasani Moghaddam Mohamad Javad Khodam Seyyed Mohammad Afghahi Hassan Tabarsi
  10.30495/jonass.2021.1929310.1011
  Background and objective: Absolute and Relative Models of Radiometric Corrections Due to the relative information provided from different parts of the globe, there are always errors when correcting images, which has led many researchers to develop local models or design أکثر

  Background and objective: Absolute and Relative Models of Radiometric Corrections Due to the relative information provided from different parts of the globe, there are always errors when correcting images, which has led many researchers to develop local models or design tools to obtain information about the situation of Atmospheric of the area under study when the satellite passes. The present study aims to present a new method for radiometric correction of satellite images.Material and methods: To apply the proposed method for correcting the calibration of satellite images, a sun-photometer was first designed and developed that can obtain atmospheric data and attenuate sunlight in the range of 400 to 950 nm in a hyperspectral mode. Sentinel-2 satellite images related to the city of Tehran were selected as a sample and in 2 days with clean and high pollution, data were obtained and the coefficients obtained were applied through a sun-photometer.Results and conclusions: Based on made assessments, the importance of radiometric corrections based on local information for satellite images become more apparent. Evaluation of the research results shows the high capability of the designed sun-photometer in accurately assessing the attenuation of sunlight in different spectral. The amount of sunlight attenuation in the green band is more than the blue and red bands, which indicates the type of urban pollution in the region, which had the greatest impact on the green band and the least impact on the red band. تفاصيل المقالة