uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Sensor Networks and Their Radio Environment: On Testbeds, Interference, and Broken Packets
Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Computer Systems. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems. (Communication Research)
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Sensor networks consist of small sensing devices that collaboratively fulfill a sensing task, such as monitoring the soil in an agricultural field or measuring vital signs in a marathon runner. To avoid cumbersome and expensive cabling, nodes in a sensor network are powered by batteries and communicate wirelessly. As a consequence of the latter, a sensor network's communication is affected by its radio environment, i.e., the environment's propagation characteristics and the presence of other radio devices. This thesis addresses three issues related to the impact of the radio environment on sensor networks.

Firstly, in order to draw conclusions from experimental results, it is necessary to assess how the environment and the experiment infrastructure affect the results. We design a sensor network testbed, dubbed Sensei-UU, to be easily relocatable. By performing an experiment in different environments, a researcher can asses the environments’ impact on results. We further augment Sensei-UU with support for mobile nodes. The implemented mobility approach adds only little variance to results, and therefore enables repeatable experiments with mobility. The repeatability of experiments increases the confidence in conclusions drawn from them.

Secondly, sensor networks may experience poor communication performance due to cross-technology radio interference, especially in office and residential environments. We consider the problem of detecting and classifying the type of interference a sensor network is exposed to. We find that different sources of interference each leave a characteristic "fingerprint" on individual, corrupt 802.15.4 packets. We design and implement the SoNIC system that enables sensor nodes to classify interference using these fingerprints. SoNIC supports accurate classification in both a controlled and an uncontrolled environment.

Finally, we consider transmission errors in an outdoor sensor network. In such an environment, errors occur despite the absence of interference if the signal-to-noise ratio at a receiver is too low. We study the characteristics of corrupt packets collected from an outdoor sensor network deployment. We find that content transformation in corrupt packets follows a specific pattern, and that most corrupt packets contain only few errors. We propose that the pattern may be useful for applications that can operate on inexact data, because it reduces the uncertainty associated with a corrupt packet.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2014. , 73 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1171
Keyword [en]
Sensor networks, Testbed, Mobility, Interference classification, Packet corruption
National Category
Communication Systems
Research subject
Computer Science with specialization in Computer Communication
Identifiers
URN: urn:nbn:se:uu:diva-230769ISBN: 978-91-554-9019-5 (print)OAI: oai:DiVA.org:uu-230769DiVA: diva2:742131
Public defence
2014-10-17, Room 1311, Polacksbacken, Lägerhyddsvägen 2, Uppsala, 13:00 (English)
Opponent
Supervisors
Projects
WISENET
Funder
VINNOVA, P26628-4
Available from: 2014-09-24 Created: 2014-08-28 Last updated: 2015-01-23
List of papers
1. Sensei-UU: a relocatable sensor network testbed
Open this publication in new window or tab >>Sensei-UU: a relocatable sensor network testbed
2010 (English)In: Proc. 5th ACM International Workshop on Wireless Network Testbeds, Experimental Evaluation and Characterization, ACM Press, 2010, 63-70 p.Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
ACM Press, 2010
Keyword
heterogeneity, mobility, testbed, wireless sensor networks
National Category
Computer Engineering Communication Systems
Research subject
Computer Science with specialization in Computer Communication
Identifiers
urn:nbn:se:uu:diva-136397 (URN)10.1145/1860079.1860091 (DOI)
Projects
WISENETProFuN
Available from: 2010-12-13 Created: 2010-12-13 Last updated: 2014-09-25Bibliographically approved
2. Repeatable experiments with mobile nodes in a relocatable WSN testbed
Open this publication in new window or tab >>Repeatable experiments with mobile nodes in a relocatable WSN testbed
Show others...
2011 (English)In: Computer journal, ISSN 0010-4620, E-ISSN 1460-2067, Vol. 54, no 12, 1973-1986 p.Article in journal (Refereed) Published
Abstract [en]

Many sensor network application scenarios include mobile nodes, such as a moving sink. Evaluatingsuch applications in a testbed is challenging since the testbed has to support mobile nodes. Wepresent Sensei-UU, a sensor network testbed that supports mobile sensor nodes. The testbedis inexpensive, relocatable and possible to reproduce by other researchers. Its primary designobjectives are to support experiments with repeatable mobility and to support relocating thetestbed deployment to different locations. Mobile sensor nodes are carried by robots that usefloor markings for navigation and localization. The testbed can be used to evaluate applicationsin which sensor nodes move in the order of meters rather than millimeters, e.g., when a humancarries a mobile phone that collects data while passing stationary sensor nodes. To investigate therepeatability of robot movements, we measure the achieved precision and timing of the robots, andfind that our robot localization is accurate to ±1 cm. Furthermore, we investigate variations inradio signal strengths between mobile and stationary nodes. We study the impact of imprecisemovements, external sources of interference, and environmental influences. We conclude thatSensei-UU supports experiments in which these variations are acceptably low to capture small-scalefading phenomena in IEEE 802.15.4.

National Category
Computer Engineering Signal Processing
Research subject
Computer Science with specialization in Computer Communication; Electrical Engineering with specialization in Signal Processing
Identifiers
urn:nbn:se:uu:diva-151814 (URN)10.1093/comjnl/bxr052 (DOI)000298386300005 ()
Projects
WISENETProFuN
Available from: 2011-04-18 Created: 2011-04-18 Last updated: 2017-12-11Bibliographically approved
3. A Lightweight Approach to Online Detection and Classification of Interference in 802.15.4-based Sensor Networks
Open this publication in new window or tab >>A Lightweight Approach to Online Detection and Classification of Interference in 802.15.4-based Sensor Networks
2012 (English)In: ACM SIGBED Review, ISSN 1551-3688, Vol. 9, no 3, 11-20 p.Article in journal (Refereed) Published
Abstract [en]

With a rapidly increasing number of devices sharing access to the 2.4 GHz ISM band, interference becomes a serious problem for 802.15.4-based, low-power sensor networks. Consequently, interference mitigation strategies are becoming commonplace. In this paper, we consider the step that precedes interference mitigation: interference detection. We have performed extensive measurements to characterize how different types of interferers affect individual 802.15.4 packets. From these measurements, we define a set of features which we use to train a neural network to classify the source of interference of a corrupted packet. Our approach is sufficiently lightweight for online use in a resource constrained sensor network. It does not require additional hardware, nor does it use active spectrum sensing or probing packets. Instead, all information about interferers is gathered from inspecting corrupted packets that are received during the sensor network’s regular operation. Even without considering a history of earlier packets, our approach reaches a mean classification accuracy of 79.8%, with per interferer accuracies of64.9% for WiFi, 82.6% for Bluetooth, 72.1% for microwave ovens, and 99.6% for packets that are corrupted due to insufficient signal strength.

National Category
Computer Engineering Communication Systems
Identifiers
urn:nbn:se:uu:diva-179803 (URN)10.1145/2367580.2367582 (DOI)
Conference
3rd International Workshop on Networks of Cooperating Objects (CONET 2012)
Projects
WISENET
Available from: 2012-08-23 Created: 2012-08-23 Last updated: 2014-09-25Bibliographically approved
4. SoNIC: Classifying interference in 802.15.4 sensor networks
Open this publication in new window or tab >>SoNIC: Classifying interference in 802.15.4 sensor networks
Show others...
2013 (English)In: Proc. 12th International Conference on Information Processing in Sensor Networks, New York: ACM Press, 2013, 55-66 p.Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
New York: ACM Press, 2013
National Category
Computer Systems
Research subject
Computer Science with specialization in Computer Communication
Identifiers
urn:nbn:se:uu:diva-198284 (URN)10.1145/2461381.2461392 (DOI)978-1-4503-1959-1 (ISBN)
Conference
IPSN 2013
Projects
WISENETProFuN
Funder
Vinnova
Available from: 2013-04-11 Created: 2013-04-11 Last updated: 2014-09-25Bibliographically approved
5. All is not lost: Understanding and exploiting packet corruption in outdoor sensor networks
Open this publication in new window or tab >>All is not lost: Understanding and exploiting packet corruption in outdoor sensor networks
Show others...
2014 (English)In: Wireless Sensor Networks: EWSN 2014, Springer Berlin/Heidelberg, 2014, 116-132 p.Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Springer Berlin/Heidelberg, 2014
Series
Lecture Notes in Computer Science, 8354
National Category
Computer Science Communication Systems
Identifiers
urn:nbn:se:uu:diva-211736 (URN)10.1007/978-3-319-04651-8_8 (DOI)000340395900008 ()978-3-319-04650-1 (ISBN)
Conference
11th European Conference on Wireless Sensor Networks, Feb 17-19, 2014, Oxford, England
Projects
WISENETProFuN
Available from: 2013-11-29 Created: 2013-11-29 Last updated: 2016-08-26Bibliographically approved

Open Access in DiVA

fulltext(4213 kB)749 downloads
File information
File name FULLTEXT01.pdfFile size 4213 kBChecksum SHA-512
1d1c5b6eb0d50150bda78fed6a8757c60f34ee28f10a3949695b341010dbd531e924429479c020ad865d47712d900ba2648e600372ae27a62002c4d6f3108fc0
Type fulltextMimetype application/pdf
Buy this publication >>

Authority records BETA

Hermans, Frederik

Search in DiVA

By author/editor
Hermans, Frederik
By organisation
Division of Computer SystemsComputer Systems
Communication Systems

Search outside of DiVA

GoogleGoogle Scholar
Total: 749 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1335 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf