Adaptive source localization with unknown permittivity and path loss coefficients

In wireless sensor network (WSN) and signal source localization tasks, permittivity and path loss coefficients, which characterize the specific signal propagation properties of the environment, have vital importance on the accuracy of location estimates. Therefore, these coefficients need to be accurately known or estimated for the effectiveness of the localization algorithm. In this paper, we propose a geometric cooperative technique to instantaneously estimate such coefficients, with details provided for received signal strength (RSS) and time-of-flight (TOF) based range sensors. Further, a discrete time recursive least squares (RLS) based adaptive localization scheme employing the proposed environmental propagation coefficient estimation technique is derived. Simulation studies, based on an unmanned aerial vehicle (UAV) localization scenario, of this adaptive localization scheme well demonstrate the effectiveness of the integration of the adaptive localization scheme and the proposed coefficient estimation technique.