A new splitting-merging paradigm for distributed localization in wireless sensor networks

This paper proposes a new merging (stitching) scheme for distributed localization of wireless sensor networks. In splitting-merging localization techniques, the network is first split into small sub-networks and each sub-network self-localizes itself, possibly in its own rather than a global coordinate basis. Then by using a stitching strategy they are merged back to compute the position of the nodes in a global coordinate basis. Unlike the existing techniques in which the stitchable sub-networks must have at least 3 nodes in common for the stitching to succeed, the proposed method can systematically address all possible scenarios (even when the two sub-networks are disjoint) while keeping the computational complexity fairly low. The scheme puts the idea of four-bar linkage mechanism and bilateration together in tackling the problem. Therefore, theoretically the proposed method can localize a broader class of networks which are localizable by any splitting-stitching technique. Simulation comparisons with trilateration and wheel graphs show a considerably higher percentage of the localized nodes in this technique. This technique in conjunction with some existing distributed splitting technique, provides a total distributed localization algorithm.