By taking different kinds of measurements at the same time, it may be possible to improve accuracy target localization or reduce number sensors needed. Time-of-arrival (TOA), time-difference-of-arrival (TDOA), time delay (TD), received signal strength (RSS), and angle-of-arrival (AOA) are commonly used in wireless systems. This article first presents a new weighted least squares (WLS) algorithm...

Source localization can be achieved by employing the time-of-arrival (TOA) measurements between the source and several spatially separated sensors. In this Letter, we develop a simple and accurate algorithm for TOA-based positioning in the presence of multipath propagation. With the use of a pure reflector, the multipath TOA information can be effectively utilized. Simulation results show that ...

This paper examines the performance of time of arrival (TOA) estimation techniques for an UWB system employing a non-coherent energy collection receiver. The performance of two different algorithms, namely, the threshold-crossing (TC) and the maximum selection (MAX) algorithms, are compared in terms of TOA estimation error. The effect of the TOA estimation error on position calculation is evalu...

Precise time-of-arrival (TOA) estimation is one of the most important techniques in RF-based positioning systems that use wireless sensor networks (WSNs). Because the accuracy of TOA estimation is proportional to the RF signal bandwidth, using broad bandwidth is the most fundamental approach for achieving higher accuracy. Hence, ultra-wide-band (UWB) systems with a bandwidth of 500 MHz are comm...

Location finding for CDMA subscribers using an antenna m a y at the base station is studied in this paper. Two methods are considered for radio location that are based on time of arrival (TOA) and angle of arrival (AOA) measurements. For TOA estimates, a maximum likelihood algorithm and a practical structure are proposed when an antenna array is available. For AOA estimates, a least-squares (LS...

In this paper, we propose an efficient two-dimensional geo-location system for social safety robot, where its location is obtained by direction of arrival (DOA) and time of arrival (TOA) of the radio signal. The proposed system requires two reference signals while the conventional systems generally deploy more than three reference signals. For estimating TOA and DOA information together, we emp...

Ultra-wide bandwidth (UWB) technology is a viable candidate for enabling accurate localization through time of arrival (TOA) based ranging techniques. These ranging techniques exploit the high time resolution of the UWB signals to estimate the TOA of the first signal path. Nevertheless, these techniques are facing the problem of proper multipath mitigation especially in harsh propagation enviro...

© 2010 Bin Shen et al. 333 This letter proposes a non-coherent blind time-of-arrival (TOA) estimation scheme for impulse radio ultra-wideband systems. The TOA estimation is performed in two consecutive phases: the Rayleigh-quotient theorem-based coarse-signal acquisition (CSA) and the iterative-threshold-test-based fine time estimation (FTE). The proposed scheme serves in a blind manner without...

This paper presents a new time of arrival (TOA) estimation technique using an improved energy detection (ED) receiver based on the empirical mode decomposition (EMD) in an impulse radio (IR) 60 GHz millimeter wave (MMW) system. A threshold is employed via analyzing the characteristics of the received energy values with an extreme learning machine (ELM). The effect of the channel and integration...

The time-of-arrival (TOA), time-difference-ofarrival (TDOA) and signal strength (SS) methods have been widely accepted as three principal techniques for positioning a mobile station (MS) in a wireless communication system. To the best of our knowledge, previous studies tend to treat these methods separately, and less analytical results on their relationship have been reported. In this paper, th...