The location of an emitter is estimated by intercepting its signal and sharing the data among several platforms to measure the time-difference-of-arrival (TDOA) and the frequency-difference-of-arrival (FDOA). Doing this in a timely fashion requires effective data compression. A common compression approach is to use a rate-distortion criterion where distortion is taken to be the mean-square erro...

In this paper, we present measurement results of the experimental validation of the UWB localization platform under Line-Of-Sight (LOS) and Non-Line-Of-Sight (NLOS) conditions. The platform is based on the Time Difference of Arrival (TDoA) technique and the energy detection receiver. TDoA based localization systems require minimum four anchors to provide 3D position data. In order to deal with ...

Tracking a mobile node using a wireless sensor network under non-line of sight (NLOS) conditions, has been considered in this work, which is of interest to indoor positioning applications. A hybrid of time difference of arrival (TDOA) and angle of arrival (AOA) measurements, suitable for tracking asynchronous targets, is exploited. The NLOS biases of the TDOA measurements and the position and v...

Abstract To achieve more accurate measurements of the MS location, it is possible to integrate many kinds of schemes. In this paper we combine time difference of arrival (TDOA) from three base stations (BSs) and angle of arrival (AOA) information at the serving BS to give location estimation of the MS. Based on the non-line-of-sight (NLOS) environments and the knowledge of NLOS error statistics...

Time synchronization and localization are key requirements for distributed underwater systems consisting of numerous low-cost submersibles. In these systems, submersibles are highly resource constrained and typically have limited acoustic communication capability. We investigate the problem of tracking submersibles that only have the capability of receiving acoustic signals. Traditional Long Ba...

We present the design of a remotely deployable distributed wireless antenna system formed from wireless sensor network nodes. Specifically, the focus is on enhancing the detection range of a distributed wireless antenna system. The primary objective is to create a methodology to steer the beam in the desired direction to enhance radio frequency (RF) direction finding and follow-on signal recept...

Title of dissertation TIME-BASED LOCATION TECHNIQUES USING INEXPENSIVE, UNSYNCHRONIZED CLOCKS IN WIRELESS NETWORKS Matthew Yew Mun Mah, Doctor of Philosophy, 2011 Dissertation directed by Professor Ashok Agrawala Department of Computer Science The ability to measure location using time of flight in IEEE 802.11 networks is impeded by the standard clock resolution, imprecise synchronization of th...

Electromagnetic (EM) source localization has become a vital issue lately to improve civilian safety, increase the military security and mitigate the disaster effect. The localization is embedded in battle-field surveillance, traffic alert, emergency call 911 (E911), resource allocation and mitigation of disaster effect. The location of the emitter can be determined by bestowing its transmitted ...

Local Positioning Systems (LPS) are supposing an attractive research topic over the last few years. LPS ad-hoc deployments of wireless sensor networks for particularly adapt to environment characteristics in harsh environments. Among LPS, those based on temporal measurements stand out their trade-off among accuracy, robustness and costs. But, regardless architecture considered, optimization dis...

Time difference of arrival (TDOA) estimation is one of the key techniques in array signal processing and has wide applications in hands-free speech interface. TDOA is used to derive the time difference of signal propagation from source to the spatially separated microphones. The acoustic transfer functions ratio (ATF-s ratio) method is one of the robust approaches to get TDOA estimate in presen...