Distributed Localization of a RF Target in NLOS Environments

A NLOS Localization Algorithm Based on BPNN

Artificial neural network (ANN) is a humanly constructed network which is based on the human brain neural network. BP neutral network (BPNN), as a typical forward ANN, can approximate any nonlinear continuous rational function. In this paper we use the BPNN to modify the Non-Line-of-Sight (NLOS) Time Difference of Arrival (TDOA) measurement value to make it closer to the Line-of-Sight (LOS) mea...

Localization and dynamic link detection for geographic routing in non-line-of-sight (NLOS) environments

IEEE 802.15.4a networks can provide the geographic routing solution with high location accuracy for the indoor environments. However, in the non-line-of-sight (NLOS) environments, the IEEE 802.15.4a networks may have a large scale location error and an unstable communication link. In this article, we propose a location estimation and dynamic link detection scheme for the geographic routing in t...

CRLBs for WSNs localization in NLOS environment

Determination of Cramer-Rao lower bound (CRLB) as an optimality criterion for the problem of localization in wireless sensor networks (WSNs) is a very important issue. Currently, CRLBs have been derived for line-of-sight (LOS) situation in WSNs. However, one of major problems for accurate localization in WSNs is non-line-of-sight (NLOS) propagation. This article proposes two CRLBs for WSNs loca...

Moving target localization in indoor wireless sensor networks mixed with LOS/NLOS situations

Indoor target localization is an essential and fundamental issue for wireless sensor networks (WSN). However, it is rather difficult for WSN to maintain the localization accuracy in line-of-sight (LOS) and non-line-of-sight (NLOS) mixed environment. NLOS propagation always leads to larger ranging error than LOS does. When the target moves in the rooms and corridors, the signal transmission stat...

WiMAX Technology LOS and NLOS Environments