A graph-based approach to assist TDOA based localization

In multidimensional source localization based on time difference of arrival (TDOA), it is difficult to identify the direct-path TDOA among all TDOA estimates of one sensor pair and to find the corresponding TDOA values belonging to the same source among different sensor pairs. In this paper, we present a graph based approach to solve this problem. It relies on the concept of consistent graph whose sum of edge weights along all loops is zero. We introduce the concept of consistent graph and reformulate the above TDOA matching task as a synthesis of consistent graphs. We prove the feasibility of a bottom-up synthesis of consistent graphs by using fundamental loops. Finally, we present an efficient synthesis algorithm by exploiting a search in a compatibility-conflict graph.