Error Control for Wireless Ad-Hoc and Sensor Network Localization

MPhil Thesis Defence


Title: "Error Control for Wireless Ad-Hoc and Sensor Network Localization"

By

Mr. Lirong Jian


Abstract

Location information is essential for a wide range of wireless ad-hoc and 
sensor network applications. A number of localization approaches have been 
proposed, most of which are based on inter-node distance. However, errors 
are inevitable in distance measurements and we observe that a small number 
of outliers can degrade localization accuracy drastically. In this thesis, 
we investigate a large body of existing approaches with focuses on error 
control, one rising aspect that attracts significant research interests in 
recent years. Error control aims to alleviate the negative impact of noisy 
ranging measurement and the error accumulation effect during cooperative 
localization process. We formally define the outlier detection problem for 
network localization and build a theoretical foundation to identify 
outliers based on graph embeddability and rigidity theory. Our analysis 
shows that the redundancy of distance measurements plays an important 
role. We then design an outlier detection algorithm based on bilateration 
generic cycles, and examine its effectiveness and efficiency through a 
network prototype of MicaZ motes. Extensive simulations are also conducted 
on the data sets from a real-world system. The results show that our 
design significantly improves the localization accuracy by wisely 
rejecting outliers.


Date:			Tuesday, 29 June 2010

Time:			12:00noon – 2:00pm

Venue:			Room 3494
 			Lifts 25/26

Committee Members:	Dr. Yunhao Liu (Supervisor)
 			Dr. Ke Yi (Chairperson)
 			Dr. Lin Gu


**** ALL are Welcome ****