对温室气体进行全球范围的高精度监测, 获取高可靠有效数据, 是实现对温室气体排放进行监控的基础。为了实现温室气体的亚纳米高光谱分辨率光谱探测, 需要保证高光谱温室气体监测仪探测系统具有高信噪比。围绕仪器信号链路的关键模块——InGaAs面阵探测器的信息获取与处理模块, 开展了微弱光谱信号低噪声信息获取和处理技术的研究。设计了微弱光谱信号低噪声信息获取和处理系统, 并深入研究了影响光谱探测系统噪声的重要因素。通过构建谱段信噪比模型, 并采用小带宽运放电路和AD多次采样方法降低电路噪声, 系统在1.61μm谱段0.07nm光谱分辨率下, 典型能量值为1.91W/(μm·m2·sr), 信噪比(SNR)达340。实验结果表明, 系统噪声均方差(RMS)值为8.1LSB, 优于10LSB(4.9mV噪声), 实现了高光谱温室气体监测仪对亚纳米微弱光谱信号探测的高信噪比需求。该低噪声信号获取与处理技术为InGaAs面阵探测器在温室气体监测应用领域的微弱光谱信号探测打下了基础。

The high-precision monitoring of greenhouse gases on a global scale and the acquisition of highly reliable and effective data are the basis for monitoring greenhouse gas emissions. In order to achieve sub-nm hyperspectral resolution spectral detection of greenhouse gases, it is necessary to ensure a high signal-to-noise ratio of the high-spectrum greenhouse gas monitor detection system. In this paper, as the key module of the instrument signal link, the information acquisition and processing module of InGaAs area array detector is studied. A low-noise information acquisition and processing system for weak spectral signals is designed, and important factors affecting the noise of the spectral detection system are analyzed. By constructing a spectral signal-to-noise ratio model and using a small-bandwidth op-amp circuit and AD multi-sampling method to reduce the circuit noise, the system obtains a typical energy value of 1.91W/μm at a spectral resolution of 0.07nm in the 1.61μm spectrum. When the typical enery value is 1.91W/(μm·m2·sr), the signal-to-noise ratio reaches 340. The experimental results show that the mean square error (RMS) of the system noise is 8.1LSB, which is better than 10LSB (4.9mV noise), realizing a high signal-to-noise ratio of the high-spectrum greenhouse gas monitor for sub-nano weak spectral signal detection. The low-noise signal acquisition and processing technology lays the foundation for the detection of weak spectral signals in the field of greenhouse gas monitoring applications by InGaAs area array detectors.