Non-line-of-sight (NLOS) identification and mitigation carry significant importance in wireless localization systems. In this paper, we propose a novel NLOS identification technique based on the multipath channel statistics such as the kurtosis, the mean excess delay spread, and the root-mean-square delay spread. In particular, the IEEE 802.15.4a ultrawideband channel models are used as example...

Non-line-of-sight (NLOS) geolocation becomes an important issue with the fast development of mobile communications in recent years. Several methods have been proposed to address this problem. However, a comprehensive study on the best geolocation accuracy that these methods may possibly achieve is called for. In [1], [2], we reported a unified analysis of the CramerRao Lower Bound (CRLB) and ac...

A Non-light-of-sight (NLOS) mitigation approach based on GBSBEM was proposed in this paper. The main idea is to model the NLOS errors to the elliptical model and mitigate them with a novel method. At the first step, the semi-minor of GBSBEM is estimated, then a way to restrain the NLOS errors with the help of the semi-minor is used. When the semi-minor can not be estimated, an optimization meth...

Performance of Ultra-wideband (UWB) radios in non-line-of-sight (NLoS) environments has been a topic of interest among researchers, especially when it comes to indoor localization applications. It is known that NLoS propagation of electromagnetic waves can severely affect the localization accuracy. Despite the interest in indoor localization performance, it is still difficult to compare results...

:lhstr,,c/This paper deals with thc problem of non-line-of-sight (NLOS) in wireless coinniunications systems devoted to location purpnses. I t i s WEII known that NLOS biases time o f nr r iva l ('rO+\) 21nd Time Difference of Arrival (TDOA) estimates thus rcduring accuracy of positioning algorithms. I n urder to achieve positioning error reduction the Kalman filter proposed for Iorntion estima...

Non-line-of-sight (NLOS) propagation can severely degrade the reliability of communication and localisation accuracy in indoor ultra-wideband (UWB) ‘location-aware’ networks. Link adaptation and NLOS bias mitigation techniques have respectively been proposed to alleviate these effects, but implicitly rely on the ability to accurately distinguish between LOS and NLOS propagation scenarios. A sta...

An ultraviolet (UV) signal transmission undergoes rich scattering and strong absorption by atmospheric particulates. We develop a path loss model for a Non-Line-of-Sight (NLOS) link. The model is built upon probability theory governing random migration of photons in free space, undergoing scattering, in terms of angular direction and distance. The model analytically captures the contributions o...

Non-line-of-sight (NLoS) maritime mobile radio channel in 5 GHz band is experimentally investigated in this paper through wideband channel soundings. During the measurements, the transmitter was installed onboard a speed boat, while the receiver was placed on the roof top of a building on shore. Different types of cargo ships anchored off the east coast of Singapore were examined as obstruction...

Indoor localization systems that are accurate and robust with respect to propagation channel conditions are still a technical challenge today. In particular, for systems based on range measurements from radio signals, non-line-of-sight (NLOS) situations can result in large position errors. In this paper, we address these issues using measurements in a representative indoor environment. Results ...

Network mobilephone-based positioning experiences degradation of location accuracy due to localised non-line-of-sight (NLOS) signal propagation. This is well known to be a major source of error in network-based mobilephone positioning. NLOS error systematically causes the Mobile Station (MS) to appear further away from the base station than it actually is, thereby increasing the positioning err...