Research On Low-noise Electronics Technology Of Hyperspectral InGaAs Area Array For Carbon Dioxide Monitoring

High-precision monitoring of greenhouse gases on a global scale and access to high-reliability and effective data are essential tools for controlling greenhouse gas emissions.In order to obtain high-precision data,hyperspectral greenhouse gas monitors need to achieve sub-nanometer resolution spectral detection with high signal-to-noise ratio.In this paper,the information acquisition and processing module of InGaAs area array detector,one of the key modules of the instrument signal link,is used to study the low-noise electronics of weak spectral signals,so as to guarantee the typical spectral resolution of 1.61 um in the 1.61 um spectrum.The signal-to-noise ratio at the energy value of 1.91 W/um/m2 /sr meet application requirements.The key technologies of the information acquisition and processing system of the focus plane device are studied,and the important factors affecting the system noise are analyzed.The signal-to-noise ratio model of the spectrum segment is proposed,and the quantization noise requirements for the key modules are obtained.Based on this,the weak spectral signal low noise is discussed in detail.The design flow and peripheral circuits of the information module.The paper firstly investigates the status quo of remote sensing technology for greenhouse gases at home and abroad,and briefly introduces the detection methods and performance indicators of on-orbit monitors at home and abroad.On this basis,the information acquisition and processing technology based on infrared area array focal plane detector is investigated,and the measures taken to reduce system noise and its development results are analyzed.By comparing the advantages and disadvantages of the existing schemes,combined with the performance indicators of the hyperspectral greenhouse gas monitor and the characteristics of the InGaAs focal plane detector,the function of the detector information acquisition and processing module of one of the key modules of the instrument signal link is analyzed.And performance requirements.According to the characteristics of InGaAs 1300×300 focal plane detector,a scheme for calculating the noise of the electronic module based on system noise is proposed to realize high signal-to-noise ratio.Based on the scheme,the factors affecting the system noise are quantitatively analyzed.The main noise sources of the system are shot noise,background noise,information acquisition and processing circuit noise,and the noise mathematical model of the detector,information acquisition and processing module is established.Aiming at the readout signal characteristics of the InGaAs short-wave infrared component focal plane device,the low noise information acquisition circuit,including the drive and bias and signal conditioning circuit design of the focal plane device,is designed and implemented with FPGA as the core.Methods and PCIe-based data acquisition and transmission methods.The low noise requirement of the information acquisition circuit is fully considered in the design.The low noise design is made for the power module,the focal plane device bias circuit,the analog signal conditioning circuit and the PCB,and the noise mathematical model of the information acquisition circuit is established and analyzed.The experimental platform of the InGaAs short-wave infrared focal plane device experimental system was built,and the noise performance of the information acquisition circuit was tested.The data related to the information acquisition and processing circuit was tested and analyzed,and the final noise results were statistically calculated.The experimental results show that the system noise mean square error(RMS)is 8.1 LSB and less than 10 LSB(4.9 m V noise),which satisfies the application requirements of high-spectrum greenhouse gas monitor for high signal-to-noise ratio under weak spectral signals.