Author : Oziel Hernández Salgado
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (768 download)
Book Synopsis Position Location Estimation in Ad-hoc Networks Using a Dead Reckoning Approach by : Oziel Hernández Salgado
Download or read book Position Location Estimation in Ad-hoc Networks Using a Dead Reckoning Approach written by Oziel Hernández Salgado and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Classical multilateration techniques for position estimation assume direct connectivity between land reference nodes and a node whose location we want to estimate, but in the case of ad-hoc networking position location schemes use pair-wise range and angle of arrival estimates made between all the nodes and their neighbors. In ad-hoc networks, devices are not required to be in range of fixed Access Points like in common cellular systems, instead, a few known-location devices in the network allow the remaining devices to calculate their location using a method called Dead Reckoning that is the process of estimating location based solely on consecutive distance and direction of travel estimates parting from the last known position. The distance vectors between each base station and the node of interest calculated using dead reckoning are different from the real distance due to the error created by the environmental conditions and by the hardware used to estimate the angle of arrival and time of arrival. This work presents a Maximum Likelihood estimator and its performance is compared versus a Linearized Weighted Least Squares estimator previously proposed in [1] assuming that the resultant error from the dead reckoning method has a M-Erlang distribution (exponentially distributed multipath interarrival times) and the availability of angle of arrival and time of arrival information at every node in the network. In addition we derive the Cramer-Rao Bound for the maximum likelihood estimator in order to evaluate the performance of the proposed method with respect to the number of available access points, time of arrival estimation accuracy and node density.