A Multi-Hop Localization Algorithm Based on Path Tortuosity Correction and Hierarchical Anchor Extension for Wireless Sensor Networks

In wireless sensor networks (WSNs), node localization technology serves as a critical foundation for Internet of Things (IoT) applications such as environmental monitoring and ecological protection. High-precision localization has long been a key challenge in IoT applications. However, traditional multi-hop localization algorithms suffer from insufficient localization accuracy in complex environments due to path tortuosity and error accumulation. To address this issue, this paper proposes DV-Hop-HLPT, a multi-hop localization algorithm based on a tortuosity model and a hierarchical strategy for reliable anchor nodes. The algorithm employs a hierarchical localization strategy to expand the anchor node set, incorporating high-precision localized nodes into the anchor node collection through received signal strength indication (RSSI) calibration and evaluating their reliability. To address the multi-hop path tortuosity problem, the algorithm constructs a tortuosity weight model by analyzing path information between anchor nodes, enabling dynamic correction of multi-hop path lengths. Combined with an incremental shortest path first (ISPF) algorithm to limit search depth, the approach enhances adaptability to dynamic networks. Finally, utilizing the tortuosity model and anchor node reliability, the unknown node coordinates are solved through regularized weighted least squares method. Experimental results demonstrate that under square and C-shaped network topologies, DV-Hop-HLPT reduces average normalized localization error by 50.15% and 70.95%, respectively, compared with DV-Hop, and shows significant improvements over other enhanced algorithms, effectively addressing the localization accuracy degradation problem caused by sparse anchor nodes in complex environments.