Research on High-Precision Gas Concentration Inversion for Imaging Fourier Transform Spectroscopy Based on Multi-Scale Feature Attention Model

The accurate monitoring of greenhouse gas (GHG) concentrations is crucial in mitigating global warming. The imaging Fourier transform spectrometer (IFTS) is an effective tool for measuring GHG concentrations, offering high throughput and a wide spectral measurement range. In order to address the issue of spectral inconsistency during the detection process of the target gas, which is influenced by external environmental factors, making it difficult to achieve high-precision gas concentration inversion, this paper proposes a multi-scale feature attention (MDISE) model. The model uses a multi-scale dilated convolution (MD) module to retain both global and local shallow features of the spectra; introduces the one-dimensional Inception (1D Inception) module to further extract multi-scale deep features; and incorporates the channel attention mechanism (SE) module to enhance attention to important spectral wavelengths, suppressing redundant and interfering information. A target gas detection system was built in the laboratory, and the proposed model was tested on gas samples collected by two channels of a short and medium-wavelength infrared imaging Fourier transform spectrometer (SMWIR-IFTS). The experimental results show that the MDISE model reduces the root mean square error (RMSE) in both channels by 79.14%, 76.59%, and 69.80%, and 81.45%, 82.65%, and 74.01%, respectively, compared to the partial least squares regression (PLSR), support vector regression (SVR), and conventional one-dimensional convolutional neural network (1D-CNN) models. Additionally, the MDISE model achieved average coefficient of determination (R2) values of 0.997 and 0.995 for the concentration intervals in both channels. The MDISE model demonstrates excellent performance and significantly improves the accuracy of GHG concentration inversion.