Adaptive iterative optimization inversion method for plume extinction coefficient of Mie-scattering lidar

Accurate, real-time inversion of the plume extinction coefficient is of great significance in remote sensing, environmental protection, and health security. This paper proposes the dual iterative ratio (DIR) method for retrieving the plume extinction coefficient, based on the ratio of the Mie scattering echo signal to the background signal with adaptive iterative optimization. Simulation tests demonstrate that the DIR method performs well under low signal-to-noise ratios (SNR) and is compatible with varying plume concentrations and lidar ratios; when the SNR exceeds 10, the average relative error is Less than 0.343. The algorithm is insensitive to changes in the geometric factor caused by optical misalignment: with a 1.0 mrad boresight offset in a coaxial transceiver lidar, the average relative error changes by only 4.55%. In experiments, the DIR method exhibits a strong correlation with classical inversion algorithms and achieves an average relative error of 0.131, outperforming classical methods. The measured average computation time is 80.8ms, making it suitable for real-time detection systems. The proposed algorithm provides a convenient and accurate approach of obtaining the plume extinction coefficient, addressing a technical gap in the field.