Data Repair And Confirm Of Thermal Infrared Band Of HY-1B/COCTS Under Cold Space Abnormal

As one of the most important ocean research elements,sea surface temperature(SST)is of great significance for climate and hydrological observation,ecological resource detection,and natural disaster monitoring.In order to build a maritime power and accelerate the development and utilization of marine resources,our country has successively launched four sun-synchronous orbit Ocean-One series of remote sensing satellites for water color and water temperature.Among them,the Ocean-One-B satellite(HY-1B)was launched in 2007 and stopped working in 2015.The main payload Ocean Water Temperature Scanner(COCTS)onboard has accumulated abundant ocean telemetry data after 9 years of operation in orbit.It provides a solid data foundation for scientific research and coastal construction in my country's seas,and has great potential value for the country's economic development and the construction of national defense science and technology.However,due to the interference of unknown radiation in the cold air during the on-orbit operation,the zero-radiation reference of the water-color water temperature scanner has shifted.The cold air anomaly caused the remote measurement results of all detection channels to the earth target signal to be far less than the true value,and aggravated it.The non-uniformity of the thermal infrared dualchannel remote sensing image.This article will focus on the data repair of the thermal infrared band to carry out the following work research:1.Investigate the remote sensing instruments of relevant thermal infrared band at home and abroad,look for cases of interference in cold air during on-orbit work,summarize and analyze their respective solutions,and consider whether they have the potential for universality,in order to solve HY-1B/COCTS provides ideas for the problems encountered in orbit.2.Analyze the structure of the water-color water temperature scanner and the working principle of the zero-radiation reference,explore the influence of the zeroradiation reference on the output code value and image of the earth target after the zeroradiation reference is changed,and study the change law of the cold air signal.3.Analyze the data characteristics of the cold space anomaly,and determine the conversion relationship between the on-board blackbody temperature platinum resistance code value and the equivalent blackbody temperature based on the ground infrared radiation calibration,use bipolar data to establish a response repair model and a non-uniform correction model,and evaluate the model with different parameters,and evaluate the repair work by comparing the repair results with the actual sea temperature.This paper analyzes and compares the historical data of HY-1B/COCTS,and finds that the cold air anomaly in the north and south poles has little impact on the instrument,and the cold air signal changes more stable.Using the filtered bipolar data as samples,the cold air signal,black body signal,and platinum resistance code value determined the instrument response relationship over time,and established a response repair model based on recalibration coefficients,taking into account each element of the detector The affected conditions are inconsistent,and the repair accuracy is different.On the basis of the repair results,a non-uniform correction model based on the code value probability distribution for HY-1B/COCTS is designed to realize the secondary repair of the code value of non-standard elements.By the way,the problem of image banding is solved.Then the accuracy and stability of the model were evaluated,and the restoration results were inverted to the brightness temperature for comparison with other satellite data;in view of the more severe impact of band 10,the code value compensation of band 9 versus band 10 was proposed.Mechanism to achieve model optimization.Finally,the split window algorithm is used to invert the sea temperature.Under the premise of the temperature difference between day and night,the temperature difference between the inversion temperature and the actual temperature is less than 1K,which meets the design requirements of the water color meter and realizes the restoration of the target data.