In the heart of China’s coal mining regions, a groundbreaking advancement is set to revolutionize how we monitor and manage surface deformation, offering significant commercial benefits for the energy sector. Lei Duan, a researcher from The Second Exploration Team of Shandong Coalfield Geological Bureau, has spearheaded a novel approach to phase unwrapping (PU) in differential interferometric synthetic aperture radar (DInSAR) technology. This innovation promises to enhance the accuracy and reliability of mining subsidence monitoring, a critical aspect of safe and efficient coal extraction.
Traditional PU methods have long struggled with low-coherence deformation interferograms in mining areas, leading to inaccuracies and inefficiencies. Duan’s research, published in ‘Meikuang Anquan’ (translated to ‘Coal Safety’), introduces an L2-norm PU approach driven by the matrix pencil model. This method accurately extracts wrapped phase gradients in four directions—horizontal, vertical, and the two diagonals—using an improved matrix pencil local frequency estimator. These gradients are then integrated with a four-direction weighted least squares PU algorithm, employing the Gauss-Seidel iteration method to compute the unwrapped deformation phase of the mining surface.
“The proposed approach not only preserves the advantages of high unwrapping efficiency and smooth phase surfaces but also effectively mitigates noise interference during the PU process,” Duan explains. This enhancement is crucial for the energy sector, where precise monitoring of surface deformation can prevent accidents, optimize operations, and ensure regulatory compliance.
Experimental results based on mining subsidence simulation data and real-world data from three coal mining collapse sites in Yongcheng Mining Area of Henan Province demonstrate the method’s superiority. Compared to traditional methods like minimum-cost flow, statistical-cost network-flow, and four-direction weighted least squares PU, Duan’s approach improves PU accuracy by up to 74.1%. This translates to more accurate, complete, and smooth unwrapped deformation phases, which are essential for effective mining management.
The implications of this research are far-reaching. Enhanced PU accuracy can lead to better prediction and management of mining subsidence, reducing the risk of accidents and environmental impact. For the energy sector, this means more efficient and safer coal extraction processes, ultimately contributing to more stable energy supply chains.
As the energy sector continues to evolve, the need for advanced monitoring technologies becomes increasingly critical. Duan’s research represents a significant step forward in this domain, offering a robust solution that can be integrated into existing DInSAR systems. The commercial impact is substantial, with potential applications ranging from improved safety protocols to optimized resource management.
In the words of Duan, “This new approach significantly enhances the accuracy and noise resistance of the L2-norm unwrapping model, paving the way for more reliable and efficient mining operations.” As the energy sector looks to the future, innovations like these will be key to meeting the dual challenges of sustainability and efficiency.