Third-Order Channel Propagation Model-Based Indoor Adaptive Localization Algorithm for Wireless Sensor Networks

In a changing indoor environment, it is very difficult for wireless sensor networks (WSNs) to locate adaptively the target nodes because of the complexity of the propagation path loss. In this letter, the fading characteristics of channel propagation for wireless sensor nodes are tested, the test data are fitted, and the third-order polynomial log-distance path-loss model is proposed. Using the proposed model, an indoor adaptive localization algorithm for WSNs is designed. The algorithm builds a model parameter table according to the received signal strength indication (RSSI) of fixed nodes, and the table is updated with environmental variation. In locating phase, the most suitable parameters are used to estimate the position of target node. Compared to another algorithm, the proposed algorithm improves the average localization accuracy by about 75%.