Research And Implementation Of Meteor Spectrum Extraction Method

Meteoroids enter the earth’s atmosphere to ablate and melt to produce meteor vapor.The excited atoms in the meteor vapor radiate photons outward to produce light,which is the phenomenon of meteors.The physical and chemical properties of meteoroids can be obtained from meteor.It is an emerging topic in the space environment to analyze the chemical composition of meteoroids and infer the origin of meteoroids and their impact on the Earth’s atmosphere by meteor spectrum obtained from meteor by using spectroscopic devices.In order to obtain meteor spectral data and analyze the physical and chemical properties of meteoroids,the observation and extraction method of meteor spectrum based on grating video is studied according to the luminescence phenomenon of meteoroids in the atmosphere,and meteor spectrum pipeline process flow is given in this thesis.On this basis,a meteor spectrum inversion software for processing massive data is developed.Using this software,the meteor spectrum video recorded by the observation system is processed,and a relatively rich meteor spectrum data is obtained,and a preliminary analysis of the spectrum data is carried out.The thesis mainly studies the content and conclusions are as follows:1)According to the characteristics of meteors,in order to choose suitable meteor spectrum observation equipment,the principles of spectroscopic devices and image sensors for acquiring and recording meteor spectrum are comprehensively analyzed,and diffraction gratings and charge-coupled devices selected as the devices are used in the meteor spectroscopic observation system.The design of meteor spectrum observation system is studied,and the construction scheme of hardware observation system and software monitoring system is given.The observation system is used for long-term meteor observation,and a large number of meteor spectrum video data are obtained to verify the reliability of the system.2)The most difficult task in the extraction of meteor spectra is to correct the aberrations of meteor spectra.In this thesis,based on the structure of the meteor spectrum observation system,the imaging optical path of the meteor spectrum is derived,we analyze the aberrations produced by the meteor spectra recorded by the observation system and their causes,and study the correction method of spectral aberrations by transforming the image projection method to correct the spectral aberrations.The spectral lamp experiments were used to determine the transformation parameters and spectral dispersion values,and the spectral lines were extracted from the spectral lamp experimental images by image transformation and comparison with the spectral lamp experimental data of known wavelengths to quantitatively analyze the spectral line extraction errors.The results show that the spectral line extraction error of the spectral lamp experiment is less than two pixels,which is within the acceptable range,and the causes of the error are analyzed.Finally,the meteor spectral video example data were processed using this method,and clear meteor spectral lines were obtained.3)Based on the above proposed the meteor spectrum extraction method,the processing flow of meteor spectrum video is given,and based on this,a software for processing massive meteor spectrum video data is developed,and the overall architecture of the software and the specific implementation of each module are given.The software is used to process the Sirius stellar spectra recorded by the observing system,and the measured spectra are in good agreement with the standard spectra in several specific absorption lines by comparison with the standard spectra.Then a large amount of meteor spectral data recorded by the observing system was processed to obtain meteor spectral line data,and a preliminary analysis of the velocity,ablation process,and chemical composition of the meteoroid was performed based on the extracted results.In summary,the meteor spectrum observation system designed and the established video processing flow of meteor spectrum as well as the developed frequency spectrum inversion software in thesis can effectively record and process the video data of meteor spectrum,extract clear meteor spectrum lines,obtain the physical and chemical characteristics of meteoroids,and provide important technical support for the analysis of the origin of meteoroids and their impact on the earth’s spatial environment.