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  • 1. Behboodi, Arash
    et al.
    Crombez, Pieter
    de las Heras, Jose Javier
    De Poorter, Eli
    Handziski, Vlado
    Lemic, Filip
    Moerman, Ingrid
    Van Haute, Tom
    Verhoeve, Piet
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Wolisz, Adam
    Evaluation of RF-based Indoor Localization Solutions for the Future Internet2013Conference paper (Refereed)
  • 2.
    Behboodi, Arash
    et al.
    Technical University of Berlin, Germany.
    Wirström, NIclas
    RISE, Swedish ICT, SICS.
    Lemic, Filip
    Technical University of Berlin, Germany.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Wolisz, Adam
    RISE, Swedish ICT, SICS.
    Interference Effect on Localization Solutions: Signal Feature Perspective2015In: 2015 IEEE 81st Vehicular Technology Conference (VTC Spring), 2015, 10, article id 7145885Conference paper (Refereed)
    Abstract [en]

    We study the effect of interference on localization algorithms through the study of the interference effect on signal features that are used for localization. Particularly, the effect of interference on packet-based Received Signal Strength Indicator (RSSI), reported by IEEE 802.11 and IEEE 802.15.4 technologies, and on Time of Flight (ToF), reported by IEEE 802.15.4 technology, is studied using both theoretical discussions and experimental verifications. As for the RSSI values, using an information theoretic formulation, we distinguish three operational regimes and we show that the RSSI values, in dBm, remain unchanged in the noise-limited regime, increase almost linearly with interference power in dBm in the interference-limited regime and cannot be obtained due to packet loss in the collision regime. The maximum observable RSSI variation is dependent on the transmission rate and Signal to Noise Ratio (SNR). We also show that ToF is, interestingly, decreased under interference which is caused in the symbol synchronization procedure at the receiver. After providing the experimental results, we discuss how the localization algorithms are affected by interference.

  • 3. Borissov, Nikolay
    et al.
    Anandasivam, Arun
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Neumann, Dirk
    Rational bidding using reinforcement learning: an application in automated resource allocation2008Conference paper (Refereed)
    Abstract [en]

    The application of autonomous agents by the provisioning and usage of computational resources is an attractive research field. Various methods and technologies in the area of artificial intelligence, statistics and economics are playing together to achieve i) autonomic resource provisioning and usage of computational resources, to invent ii) competitive bidding strategies for widely used market mechanisms and to iii) incentivize consumers and providers to use such market-based systems. The contributions of the paper are threefold. First, we present a framework for supporting consumers and providers in technical and economic preference elicitation and the generation of bids. Secondly, we introduce a consumer-side reinforcement learning bidding strategy which enables rational behavior by the generation and selection of bids. Thirdly, we evaluate and compare this bidding strategy against a truth-telling bidding strategy for two kinds of market mechanisms – one centralized and one decentralized.

  • 4. Borissov, Nikolay
    et al.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Q-Strategy: A Bidding Strategy for Market-Based Allocation of Grid Services2008Conference paper (Refereed)
    Abstract [en]

    The application of autonomous agents by the provisioning and usage of computational services is an attractive research field. Various methods and technologies in the area of artificial intelligence, statistics and economics are playing together to achieve i) autonomic service provisioning and usage of Grid services, to invent ii) competitive bidding strategies for widely used market mechanisms and to iii) incentivize consumers and providers to use such market-based systems. The contributions of the paper are threefold. First, we present a bidding agent framework for implementing artificial bidding agents, supporting consumers and providers in technical and economic preference elicitation as well as automated bid generation by the requesting and provisioning of Grid services. Secondly, we introduce a novel consumer-side bidding strategy, which enables a goal-oriented and strategic behavior by the generation and submission of consumer service requests and selection of provider offers. Thirdly, we evaluate and compare the Q-strategy, implemented within the presented framework, against the Truth-Telling bidding strategy in three mechanisms – a centralized CDA, a decentralized on-line machine scheduling and a FIFO-scheduling mechanisms.

  • 5.
    Duquennoy, Simon
    et al.
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Dunkels, Adam
    RISE, Swedish ICT, SICS.
    Demo: Snap – Rapid Sensornet Deployment with a Sensornet Appstore2011Conference paper (Refereed)
    Abstract [en]

    Despite ease of deployment being seen as a primary advantage of sensor networks, deployment remains difficult. We present Snap, a system for rapid sensornet deployment that allows sensor networks to be deployed, positioned, and reprogrammed through a sensornet appstore. Snap uses a smartphone interface that uses QR codes for node identification, a map interface for node positioning, and dynamic loading of applications on the nodes. Snap nodes run the Contiki operating system and its low-power IPv6 network stack that provides direct access from nodes to the smartphone application. We demonstrate rapid sensor node deployment, identification, positioning, and node reprogramming within seconds, over a multi-hop sensornet routing path with a WiFi-connected smartphone.

  • 6.
    Duquennoy, Simon
    et al.
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Tsiftes, Nicolas
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Dunkels, Adam
    RISE, Swedish ICT, SICS.
    Leveraging IP for Sensor Network Deployment2011Conference paper (Refereed)
  • 7.
    Kumm, Mia
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Fire Research.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Nilsson, Martin
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Ingason, Haukur
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Fire Research.
    Vylund, Lotta
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Fire Research.
    Safety positioning for first responders to fires in underground constructions: A pre-study of demands and possibilities2016Report (Other academic)
    Abstract [en]

    This report presents the results of the SafePos pre-study, in which different technologies for safety positioning to be used by first responders were identified, and techniques for ad hoc positioning were evaluated. The aim of the project, was to test various systems for localisation and communication and narrow- and wide-band radio transmission techniques, and to further investigate how the presence of such a system could support fire and rescue operations in complex underground environments. Tests have been carried out in real, pre-existing mining environments, and complex office corridors with similar conditions to those of a mine as regards curves and obstructions have been used for introductory tests. A computer application for digital simulation has been developed and adapted to the system, although this only operates on a relatively basic level, so as to support the testing of the positioning and communication systems; thus, more can be done to improve performance for real-life applications. The analysis was conducted by studying the results of the experiments and linking them to expected usage during a fire and rescue operation. Tests have also been carried out in cooperation with the fire and rescue services in order to identify equipment and wearable technologies that could support and make fire and rescue operations in mines and other complex underground constructions safer and more efficient. In order to transfer information to and from these wearable technologies and to improve the likelihood of a safe and efficient fire and rescue operation, positioning and connectivity are requirements.Keywords: Underground constructions, mine, fire safety, positioning, connectivity

  • 8.
    Misra, Prasant
    et al.
    RISE, Swedish ICT, SICS. Indian Institute of Science, India.
    Hu, Wen
    CSIRO, Australia.
    Jin, Yuzhe
    Microsoft, USA.
    Liu, Jie
    Microsoft, USA.
    Souza de Paula, Amanda
    University of Sao Paulo, Brazil.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Energy Efficient GPS Acquisition with Sparse-GPS2014Conference paper (Refereed)
    Abstract [en]

    Following rising demands in positioning with GPS, low-cost receivers are becoming widely available; but their energy demands are still too high. For energy efficient GPS sensing in delay-tolerant applications, the possibility of offloading a few milliseconds of raw signal samples and leveraging the greater processing power of the cloud for obtaining a position fix is being actively investigated. In an attempt to reduce the energy cost of this data offloading operation, we propose Sparse-GPS1: a new computing framework for GPS acquisition via sparse approximation. Within the framework, GPS signals can be efficiently compressed by random ensembles. The sparse acquisition information, pertaining to the visible satellites that are embedded within these limited measurements, can subsequently be recovered by our proposed representation dictionary. By extensive empirical evaluations, we demonstrate the acquisition quality and energy gains of Sparse-GPS. We show that it is twice as energy efficient than offloading uncompressed data, and has 5-10 times lower energy costs than standalone GPS; with a median positioning accuracy of 40m.

  • 9. Nimis, Jens
    et al.
    Anandasivam, Arun
    Borissov, Nikolay
    Smith, Garry
    Neumann, Dirk
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Rosenberg, Erel
    Villa, Matteo
    SORMA - business cases for an open grid market: concept and implementation2008Conference paper (Refereed)
    Abstract [en]

    Economic mechanisms enhance technological solutions by setting the right incentives to reveal information about demand and supply accurately. Market or pricing mechanisms are ones that foster information exchange and can therefore attain efficient allocation. By assigning a value (also called utility) to their service requests, users can reveal their relative urgency or costs to the service. The implementation of theoretical sound models induce further complex challenges. The EU-funded project SORMA analyzes these challenges and provides a prototype as a proof-of-concept. In this paper the approach within the SORMA-project is described on both conceptual and technical level.

  • 10.
    Pettinato, Paolo
    et al.
    RISE, Swedish ICT, SICS.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Eriksson, Joakim
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Multi-Channel Two-way Time of Flight Sensor Network Ranging2012Conference paper (Refereed)
    Abstract [en]

    Two-way time of flight (ToF) ranging is one of the most interesting approaches for localization in wireless sensor networking since previous ToF ranging approaches using commercial off-the-shelf (COTS) devices have achieved good accuracy. The COTS-based approaches were, however, evaluated only in line-of-sight conditions. In this paper, we extend ToF ranging using multiple IEEE 802.15.4 channels. Our results demonstrate that with multiple channels we can achieve good accuracy even in non line-of-sight conditions. Furthermore, our measurements suggest that the variance between different channels serves as a good estimate of the accuracy of the measurements, which can be valuable information for applications that require localization information.

  • 11.
    Sundström, Petra
    et al.
    RISE, Swedish ICT, SICS.
    Kosmack Vaara, Elsa
    RISE - Research Institutes of Sweden, ICT, SICS.
    Solsona Belenguer, Jordi
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Lundén, Marcus
    RISE, Swedish ICT, SICS.
    Laaksolahti, Jarmo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Waern, Annika
    RISE, Swedish ICT, SICS.
    Höök, Kristina
    RISE, Swedish ICT, SICS.
    Experiential Artifacts as a Design Method for Somaesthetic Service Development2011Conference paper (Refereed)
  • 12.
    Sundström, Petra
    et al.
    RISE, Swedish ICT, SICS.
    Taylor, Alex
    Grufberg, Katja
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Solsona Belenguer, Jordi
    Lundén, Marcus
    RISE, Swedish ICT, SICS.
    Inspirational Bits - Towards a Shared Understanding of the Digital Material2011Conference paper (Refereed)
    Abstract [en]

    In any design process, a medium’s properties need to be considered. This is nothing new in design. Still we find that in HCI and interactive systems design the properties of a technology are often glossed over. That is, technologies are black-boxed without much thought given to how their distinctive properties open up design possibilities. In this paper we describe what we call inspirational bits as a way to become more familiar with the design material in HCI, the digital material. We describe inspirational bits as quick and dirty but fully working systems in both hardware and software built with the aim of exposing one or several of the dynamic properties of a digital material. We also show how they provide a means of sharing design knowledge across the members of a multi-disciplined design team.

  • 13.
    Sundström, Petra
    et al.
    RISE, Swedish ICT, SICS.
    Taylor, Alex
    Grufberg, Katja
    supple.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Solsona Belenguer, Jordi
    Lundén, Marcus
    RISE, Swedish ICT, SICS.
    Inspirational bits: towards a shared understanding of the digital material2011Conference paper (Refereed)
    Abstract [en]

    In any design process, a medium's properties need to be considered. This is nothing new in design. Still we find that in HCI and interactive systems design the properties of a technology are often glossed over. That is, technologies are black-boxed without much thought given to how their distinctive properties open up design possibilities. In this paper we describe what we call inspirational bits as a way to become more familiar with the design material in HCI, the digital material. We describe inspirational bits as quick and dirty but fully working systems in both hardware and software built with the aim of exposing one or several of the dynamic properties of a digital material. We also show how they provide a means of sharing design knowledge across the members of a multi-disciplined design team.

  • 14.
    Van Haute, Tom
    et al.
    Ghent University, Belgium.
    De Poorter, Eli
    Ghent University, Belgium.
    Crombez, Pieter
    Televic NV, Belgium.
    Lemic, Filip
    Technical University of Berlin, Germany.
    Handziski, Vlado
    Technical University of Berlin, Germany.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Wolisz, Adam
    Technical University of Berlin, Germany.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Moerman, Ingrid
    Ghent University, Belgium.
    Performance Analysis of Multiple Indoor Positioning Systems in a Healthcare Environment2016In: International Journal of Health Geographics, ISSN 1476-072X, E-ISSN 1476-072X, Vol. 15, no 7Article in journal (Refereed)
    Abstract [en]

    Background: The combination of an aging population and nursing staff shortages implies the need for more advanced systems in the healthcare industry. Many key enablers for the optimization of healthcare systems require provisioning of location awareness for patients (e.g. with dementia), nurses, doctors, assets, etc. Therefore, many Indoor Positioning Systems(IPSs) will be indispensable in healthcare systems. However, although many IPSs have been proposed in literature, most of these have been evaluated in non-representative environments such as office buildings rather than in a hospital. Methods: To remedy this, the paper evaluates the performance of existing IPSs in an operational modern healthcare environment: the “Sint-Jozefs kliniek Izegem” hospital in Belgium. The evaluation (data-collecting & data-processing) is executed using a standardized methodology and evaluates the point accuracy, room accuracy and latency of multiple IPSs. To evaluate the solutions, the position of a stationary device was requested at 73 evaluation locations. By using the same evaluation locations for all IPSs the performance of all systems could objectively be compared. Results: Several trends can be identified such as the fact that Wi-Fi based fingerprinting solutions have the best accuracy result (point accuracy of 1.21 m and room accuracy of 98 %) however it requires calibration before use and needs 5.43 s to estimate the location. On the other hand, proximity based solutions (based on sensor nodes) are significantly cheaper to install, do not require calibration and still obtain acceptable room accuracy results. Conclusion: As a conclusion of this paper, Wi-Fi based solutions have the most potential for an indoor positioning service in case when accuracy is the most important metric. Applying the fingerprinting approach with an anchor installed in every two rooms is the preferred solution for a hospital environment.

  • 15.
    Van Haute, Tom
    et al.
    Ghent University, Belgium.
    De Poorter, Eli
    Ghent University, Belgium.
    Lemic, Filip
    Technical University of Berlin, Germany.
    Handziski, Vlado
    Technical University of Berlin, Germany.
    Wirström, Niclas
    RISE, Swedish ICT, SICS.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Wolisz, Adam
    Technical University of Berlin, Germany.
    Moerman, Ingrid
    Ghent University, Belgium.
    Platform for Benchmarking of RF-based Indoor Localization Solutions2015In: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 53, no 9, p. 126-133Article in journal (Refereed)
    Abstract [en]

    Over the last years, the number of indoor localization solutions has grown exponentially and a wide variety of different technologies and approaches is being explored. Unfortunately, there is currently no established standardized evaluation method for comparing their performance. As a result, each solution is evaluated in a different environment using proprietary evaluation metrics. Consequently, it is currently extremely hard to objectively compare the performance of multiple localization solutions with each other. To address the problem, we present the EVARILOS Benchmarking Platform, which enables an automated evaluation and comparison of multiple solutions in different environments and using multiple evaluation metrics. We propose a testbed independent benchmarking platform, combined with multiple testbed dependent plug-ins for executing experiments and storing performance results. The platform implements the standardized evaluation method described in the EVARILOS Benchmarking Handbook, which is aligned with the upcoming ISO/IEC 18305 standard “Test and Evaluation of Localization and Tracking Systems”. The platform and the plugins can be used in real-time on existing wireless testbed facilities, while also supporting a remote offline evaluation method using precollected data traces. Using these facilities, and by analyzing and comparing the performance of three different localization solutions, we demonstrate the need for objective evaluation methods that consider multiple evaluation criteria in different environments.

  • 16. Van Haute, Tom
    et al.
    De Poorter, Eli
    Rossey, Jen
    Moerman, Ingrid
    Handziski, Vlado
    Behboodi, Arash
    Lemic, Filip
    Wolisz, Adam
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Combez, Pieter
    Verhoeve, Piet
    de las Heras, Jose Javier
    The EVARILOS Benchmarking Handbook: Evaluation of RF-based Indoor Localization Solutions2013Conference paper (Refereed)
  • 17.
    Wirström, Niclas
    et al.
    RISE, Swedish ICT, SICS.
    Behboodi, Arash
    Technical University of Berlin, Germany.
    Lemic, Filip
    Technical University of Berlin, Germany.
    Wolisz, Adam
    Technical University of Berlin, Germany.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Localization using Anonymous Measurements2015In: 2015 International Conference on Distributed Computing in Sensor Systems, 2015, 10, p. 137-146, article id 7165032Conference paper (Refereed)
    Abstract [en]

    Range-based IEEE 802.15.4 localization systems currently require relatively high anchor density for indoor deployments. It can therefore be beneficial to use external sources of transmission as additional anchors. We present methods for using WiFi beacons to improve localization accuracy of a range-based IEEE 802.15.4 localization system in cases where only two IEEE 802.15.4 anchor nodes are available. We do this by identifying WiFi beacons from RSSI traces that we dynamically sample online, and applying fingerprinting and range-based methods using the RSSI values of the identified beacons. However, because the data of the WiFi traffic is not decodable by the IEEE 802.15.4 devices, these RSSI measurements lack identifiers that can associate them to specific WiFi Access Points (APs). Therefore, novel methods are required for both fingerprinting and range-based approaches to allow for these additional WiFi APs to be used as anchors. We show by using real-world measurements that our beacon identification method gives a false-positive rate of only 3%, and that if the range measurements to the IEEE 802.15.4 anchors are relatively accurate, with a standard deviation of 1 and 3 m, a localization accuracy improvement of 47% and 24% can be gained, respectively.

  • 18.
    Wirström, Niklas
    et al.
    RISE, Swedish ICT, SICS.
    Misra, Prasant
    RISE, Swedish ICT, SICS.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory. Uppsala University, Sweden.
    Spray: A Multi-Modal Localization System for Stationary Sensor Network Deployment2014Conference paper (Refereed)
    Abstract [en]

    We present a localization system that targets rapid deployment of stationary wireless sensor networks (WSN). The system uses a particle filter to fuse measurements from multiple localization modalities, such as RF ranging, neighbor information or maps, to obtain position estimations with higher accuracy than that of the individual modalities. The system isolates different modalities into separate components which can be included or excluded independently to tailor the system to a specific scenario. We show that position estimations can be improved with our system by combining multiple modalities. We evaluate the performance of the system in both an indoor and outdoor environment using combinations of five different modalities. Using two anchor nodes as reference points and combining all five modalities, we obtain RMS (Root Mean Square) estimation errors of approximately 2.5 m in both cases, while using the components individually results in errors within the range of 3.5 and 9 m.

  • 19.
    Wirström, Niklas
    et al.
    RISE, Swedish ICT, SICS.
    Misra, Prasant
    RISE, Swedish ICT, SICS.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Spray, Embracing Multimodality2013Conference paper (Refereed)
    Abstract [en]

    We present Spray, a localization system that compensates for low accuracy of individual localization measurements by combining measurements from multiple localization modalities.

  • 20.
    Österlind, Fredrik
    et al.
    RISE, Swedish ICT, SICS.
    Wirström, Niklas
    RISE, Swedish ICT, SICS.
    Tsiftes, Nicolas
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Finne, Niclas
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Voigt, Thiemo
    RISE, Swedish ICT, SICS, Computer Systems Laboratory.
    Dunkels, Adam
    RISE, Swedish ICT, SICS.
    StrawMAN: Making Sudden Traffic Surges Graceful in Low-Power Wireless Networks2010Conference paper (Refereed)
1 - 20 of 20
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