| The number and spread of forest fires have increased significantly in recent years due to the effects of global climate change and human activities.Forest fires not only destroy forest structure and cause natural disasters,but also affect social stability.Since forest fires often occur in remote areas,satellite remote sensing monitoring provides a large area of low-cost measurement advantages to a large extent.Using hyperspectral technology,it can monitor fires,simultaneous research chemical components released by fires.Based on the application of monitoring forest fire,a low cost uncooled thermal infrared hyperspectral imaging system for micro-satellite platform is researched and designed in this paper.Firstly,the present situation of forest fire monitoring by space-based remote sensing and thermal infrared hyperspectral imager are introduced.It is pointed out that the detection ability of chemical substances released by fire combustion is not enough and it is difficult to accurately grasp the occurrence of fire.Then based on the target characteristics of forest fires and the principle of remote sensing monitoring of forest fires,a low-cost uncooled infrared detector is chosen.According to the orbital height of the satellite platform,the spatial resolution,the time resolution,the spectral resolution and SNR required for fire detection,we determine the parameters for hyperspectral detection of forest fires.According to the requirements of these indicators and the miniaturization of optical systems,the structural type of the optical system are determined.Medium and long wave infrared dual-band hyperspectral imaging system is designed based on a Schwarzchild telescope and Dyson spectroscopic mount.The medium wave infrared and the long wave infrared share the same optical system,achieving the advantage of compact structure.Finally,the analysis and formulation of tolerance,the design of mechanical structure,and the analysis of stray light are carried out.The tolerance distribution results are in line with the actual processing requirements.Space dimension and spectral dimension stray light coefficient is small but its self-thermal radiation needs to be further extracted by algorithm. |
