A Node Localization Algorithm in WSNs By Using Signal Phase Searching Method

Node self-localization is one of the hot research topics in wireless sensor networks (WSNs). According to the relationship between signal phase and physical distance, a localization algorithm by using signal phase searching method for WSNs is proposed. According to the received signal phase between the anchor nodes and the unknown node, an objective function based on cosine similarity is set up in this algorithm. At this point, self-localization of an unknown node in WSN is transformed into that of searching the optimal solution of an objective function. Then, the initial search pixel can be determined by centroid localization. To reduce the complexity, gradient descent method is used to avoid the time consuming procedure of pixel-by-pixel search method. The performance is investigated by using simulated data.