Node position discovery in wireless sensor networks

Wireless sensor networks (WSN) have gained a significant attention in research and carry the promise to be helpful in numerous aspects of life. For many applications, the location information of the nodes needs to be known. As this information is not necessarily available, there is a huge interest in algorithms estimating the positions of individual nodes. The precision and computational complexity of such “localization” algorithms is still a big issue. However, there are cases where the nodes are placed in one of a few possible predetermined positions. In those cases, computing the relative positions of nodes in relation to each other might be sufficient to determine their real positions. In this study, we introduce a methodology for discovering the sequence of nodes in a unidimensional configuration using the measured Received Signal Strength(RSS) values and allowance of frequency diversity of high frequency radio (CC2420) that is frequently used in wireless sensor networks. In the reported experimental tests, we were able to determine the node sequence correctly for the nodes that are as close as 50cm to each other, using the developed methodology.