Signal Photon Extraction Method for Weak Beam Data of ICESat-2 Using Information Provided by Strong Beam Data in Mountainous Areas

The Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) can measure the elevations of Earth’s surface using a sampling strategy with unprecedented spatial detail. In daytime mountainous areas where signal–noise ratio (SNR) weak beam data is very low, current algorithms do not always perform well on extracting signal photons from (i.e., many were missed). This paper proposes an effective algorithm to extract ICESat-2 in areas. First, theoretical equation SNR for measured was derived prove that available information provided by strong be used assist extraction (that may have low areas). Then, relationship between along-track slope noise level as bridge connect data. To specific, inversed slope–noise obtained data, then rotate direction searching neighborhood Density-Based Spatial Clustering Applications Noise (DBSCAN) algorithm. With help this process, number included will significantly increase easily detected noisy photons. proposed tested Tibetan Plateau, Altun Mountains, Tianshan Mountains different seasons, results compared ATL03 datasets, ATL08 classical DBSCAN Based ground-truth visual inspection, parameters classification precision, recall, F-score our three other calculated. modified could achieve good balance precision (93.49% averaged) recall (89.34% averaged), its (more than 0.91) higher methods, which successfully continuous profile SNRs. future, are promising assess elevation accuracy achieved ICESat-2, estimate cross-track slope, further obtain ground control points (GCPs) stereo-mapping satellites