Research On Ground-based Infrared Characteristics Measurement Systems In Wide Dynamic Range Radiometry

The ground-based infrared characteristics measurement systems is one of the most important means for optical field to acquire the radiation characteristics of measured target,detect and recognize the incoming target in time,and make effective stealth assessment for the weapon in the infrared band.With the level of military hardware in our country,the infrared properties of newly-developed weapons and equipped weapons have been paid more and more attention in outfield,and it is imperative to complete the infrared characteristics measurement of these weapons.Therefore,the demand for infrared characteristics measurement is increasing gradually.Different from the laboratory,the environmental conditions are always complex and variable in outfield and the uncertain targets have been often faced up.It has been a major problem that how to improve the mobility and adaptability of systems and guarantee the accuracy of radiant calibration and measurement in outfield.The sources of error infrared radiation characteristics mainly include the operating ambient,the calibration,the internal working state,the atmospheric transmission model,the characteristics imaging of target and so on.Based on deeply studied the existing calibration methods the non-uniformity correction(NUC)characteristics measurement of target and radiation inversion,we proposed new methods on wide dynamic range of calibration,wide dynamic non-uniformity correction algorithm,radiation measurement and inversion algorithm on target in this dissertation.Contributions of the thesis are summarized as follows:1.In summary of the existing calibration methods including laboratory and outfield at home and abroad,we proposed the calibration in wide dynamic range,which is fit for complex external environment conditions.The methods improve the accuracy and ensure the mobility of system and the range of measurement.2.Considering the particularity requirements for the infrared measurement system NUC and based on the calibration-based NUC algorithm,wide dynamic non-uniformity correction algorithm is proposed.The algorithm on the one hand ensures the effectiveness of the entire radiation measurement,on the other hand guarantees the quality of the image,without periodic NUC and interruption of measurement.3.Considering the uncertain and state of target in external field,a wide dynamic range measurement method with integration time and neutral attenuator for system is proposed.A variety of key technologies to improve the measurement accuracy of infrared theodolites are proposed,covering based on a reference source method,subtracted the background method and the "3σ" principle with normal distribution method.These methods eliminate the uncertainty factors of the atmospheric transmission correction and further adapt to the external field application requirements.This dissertation systematically studies the principle of the infrared characteristics measurement system.With a variety of theoretical and experimental analysis,a wide dynamic calibration method including the wide range calibration with cavity blackbody amended by extended source and the high efficiency calibration method were proposed.Considering the periodic NUC and the quality of image and measurement,the wide dynamic NUC algorithm was proposed.The model of wide dynamic range measurement was built and based on a reference source method,subtracted the background method and the "3σ" principle with normal distribution method was proposed to improve the accuracy.The research results of this paper are important for further research on the target characteristics measurement,which is theoretical significance and practical reference value.