Surface Coverage and Recovery Strategy for 3-D Wireless Sensor Networks in Complex Mountainous Terrain

To address the issues of low coverage and local optima frequently encountered during Wireless Sensor Networks (WSNs) deployment in mountainous terrains, this study introduces a strategy called Phased Decoupling Deployment Strategy (PDDS). The PDDS improves coverage and convergence in complex terrains by decoupling optimization into three stages: terrain-based sensing pre-coverage, estimation of regional surface normals, and node height adjustment, enabling coordinated optimization of node positions and sensing orientations. Given the limited research on repairing coverage holes over 3D terrain surfaces, an additional contribution is the proposed Adaptive Redundancy Repair Strategy (ARRS). The ARRS uses a flood-fill algorithm to detect connected void regions and incorporates Principal Component Analysis (PCA) for region segmentation and directional analysis. Based on node influence and the distance between nodes and holes, it efficiently matches and schedules redundant nodes. This leads to accurate and efficient patching of coverage deficiencies. Simulation experiments reveal that the proposed approach consistently outperforms state-of-the-art methods in diverse complex terrains. It delivers notable improvements in coverage, convergence rate, and robustness. Overall, this work offers a practical solution for efficient deployment and recovery of WSNs in mountainous 3D environments.