Link quality analysis of wireless underground sensor networks

Show simple item record

dc.contributor.advisor Gruner, Stefan en
dc.contributor.postgraduate De Carvalho e Silva, Bruno Jorge en
dc.date.accessioned 2015-07-02T11:05:55Z
dc.date.available 2015-07-02T11:05:55Z
dc.date.created 2015/04/23 en
dc.date.issued 2014 en
dc.description Dissertation (MEng (Computer Engineering))--University of Pretoria, 2014. en
dc.description.abstract Wireless Sensor Networks have received significant attention due to their capability for distributed sensing at relatively low cost, in applications which range from environmental to industrial monitoring. More recently, wireless underground sensor networks have been proposed for applications such as personnel tracking in underground mines and moisture monitoring for precision agriculture. Wireless underground sensor networks are typically categorised into wireless sensor networks for mines and tunnels (which communicate overthe- air) and Subsoil Wireless underground sensor networks (which communicate wirelessly through soil). For Subsoil wireless underground sensor networks specifically, it is well known that the soil medium introduces a number of challenges. Firstly, the path loss in soil is very high. Secondly, propagation characteristics are dependent on soil conditions and properties, which can change due to irrigation or rain. Thirdly, communication in Subsoil Wireless underground sensor networks takes place over three different types of channels: underground-to-underground, aboveground-to-underground and underground-toaboveground. Therefore, communication protocols developed for over-the-air wireless sensor networks are not suitable for wireless underground sensor networks. Although some studies on wireless underground sensor networks have focussed on channel characterization, many aspects related to link characteristics have not been thoroughly investigated. Understanding the link behaviour in wireless underground sensor networks is a fundamental building block for protocol development for medium access, topology management and routing. The aim of this research is to gain insight into the link quality in wireless underground sensor networks which can aid in the development of efficient and reliable communication protocols. To this end, the link quality in the three wireless underground sensor network communication channels is characterized empirically for dry and wet soil conditions. This characterization is performed using the received signal strength, link quality indicator and packet reception rate. The results show that links in the underground-to-underground channel are very stable (in terms of received signal strength) and exhibit high symmetry and high packet reception rate, even for received signal strength values near the receiver sensitivity, but the communication ranges are limited due to the very high attenuation. On the other hand, links in the aboveground-to-underground /underground-to-aboveground channels are typically asymmetric and have longer communication ranges. For most links in all three channels, it is observed that the link quality indicator is highly variant and is not correlated with received signal strength and packet reception ratio. Furthermore, an increase in the soil moisture also affects the link asymmetry and the width of the transitional windows in the aboveground-to-underground/underground-to-aboveground channels. The results show that efficient communication protocols for wireless underground sensor networks will have to be highly adaptive/reactive to soil conditions, and link quality estimation has to be robust to the asymmetry present in most links. en
dc.description.availability Unrestricted en
dc.description.degree MEng (Computer Engineering) en
dc.description.department Electrical, Electronic and Computer Engineering en
dc.description.librarian tm2015 en
dc.identifier.citation De Carvalho e Silva, BJ 2014, Link quality analysis of wireless underground sensor networks, MEng Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/45903> en
dc.identifier.other A2015 en
dc.identifier.uri http://hdl.handle.net/2263/45903
dc.language.iso en en
dc.publisher University of Pretoria en_ZA
dc.rights © 2015 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. en
dc.subject UCTD en
dc.title Link quality analysis of wireless underground sensor networks en
dc.type Dissertation en


Files in this item

This item appears in the following Collection(s)

Show simple item record