In recent years there has been growing interest in ad-hoc and wireless sensor networks (WSNs) for a variety of indoor applications. Localization information in these networks is an enabling technology and in some applications it is the main sought after parameter. The cooperative localization performance of WSNs is constrained by the behavior of the utilized ranging technology in dense cluttere...

It is well known that non-line-of-sight (NLOS) and multipath propagation biases time of arrival (TOA) and Time Difference of Arrival (TDOA) estimates thus reducing accuracy of positioning algorithms. In order to achieve timing error reduction, a high-resolution first arriving path detector from propagation channel estimates is derived based on the minimum variance (MV) estimates and normalized ...

Abstract This paper introduces a review article on indoor localization techniques and technologies. The starts with current systems summarizes comparisons between these in terms of accuracy, cost, advantages, disadvantages. Also, the presents different detection compare them accuracy cost. Finally, methods algorithms, including angle arrival (AOA), time (TOA), recived signal strength (RSS) are ...

Signals from millisecond pulsars travel to us on geodesics along the line-of-sight that are affected by space--time metric. The exact path-geometry and redshifting determine observed Time-of-Arrival (ToA) of pulses. metric is determined distribution dark matter, gas, stars in galaxy and, final stages travel, solar system bodies. inhomogeneous stellar masses can have a small but significant stat...

In two-way time-of-arrival (TOA) systems, a user device (UD) obtains its position by round-trip communications to number of anchor nodes (ANs) at known locations. The objective function the maximum likelihood (ML) method for TOA localization is nonconvex. Thus, widely-adopted Gauss-Newton iterative solve ML estimator usually suffers from local minima problem. this paper, we convert original int...

This paper presents a novel peer-to-peer or mobileto-mobile localization scheme for general indoor and outdoor environments. In this scheme, two mobile nodes at arbitrary locations are able to locate each other without the need of Line-of-Sight (LOS) path between the two mobile device, and without the need for any reference devices such as GPS or land base beacons. Existing peerto-peer localiza...

1 Abstract In this paper a novel code tracking algorithm is proposed which can be used in GNSS receivers. Classical code tracking approaches consider AWGN channels as an hypothesis for designing theoretically optional trackers. However, this hypothesis does not hold in multipath channels. The method proposed , based on neural networks, provides results that outperform classical DLL trackers. On...

We investigate the estimation of the time of arrival (ToA) of a radio signal transmitted over a flat-fading channel. The path attenuation is assumed to depend only on the transmitter-receiver distance and the path loss exponent (PLE) which, in turn, depends on the physical environment. All previous approaches to the problem either assume that the PLE is perfectly known or rely on estimators of ...

We describe the design and evaluation of an integrated low-cost underwater sensor node designed for reconfigurability, allowing continuous operation on a relatively small rechargeable battery for one month. The node uses a host CPU for the network protocols and processing sensor data and a separate CPU performs signal processing for the ultrasonic acoustic software-defined Modulator/Demodulator...