Self-localization based on ambient signals

Abstract

We present an approach for the localization of passive nodes in a communication network using ambient radio or sound signals. In our settings the communication nodes have unknown positions. They are synchronized but do not emit signals for localization and exchange only the time points when environmental signals are received, the time differences of arrival (TDOA). The signals occur at unknown positions and times, but can be distinguished. Since no anchors are available, the goal is to determine the relative positions of all communication nodes and the environmental signals. The Ellipsoid TDOA method introduces a closed form solution assuming the signals originate from far distances. The TDOA characterize an ellipse from which the distances and angles between three network nodes can be inferred. The approach is tested in numerous simulations and in indoor and outdoor settings where the relative positions of mobile devices are determined utilizing only the sound produced by assistants with noisemakers. © 2010 Springer-Verlag.