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  • 1.
    Aeddula, Omsri
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för maskinteknik.
    Flyborg, Johan
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för hälsa.
    Larsson, Tobias
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för maskinteknik.
    Anderberg, Peter
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för hälsa.
    Sanmartin Berglund, Johan
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för hälsa.
    Renvert, Stefan
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för hälsa. Kristianstad University, SWE.
    A Solution with Bluetooth Low Energy Technology to Support Oral Healthcare Decisions for improving Oral Hygiene2021Ingår i: ACM International Conference Proceeding Series, Association for Computing Machinery (ACM), 2021, Vol. 1, s. 134-139Konferensbidrag (Refereegranskat)
    Abstract [en]

    The advent of powered toothbrushes and associated mobile health applications provides an opportunity to collect and monitor the data, however collecting reliable and standardized data from large populations has been associated with efforts from the participants and researchers. Finding a way to collect data autonomously and without the need for cooperation imparts the potential to build large knowledge banks. A solution with Bluetooth low energy technology is designed to pair a powered toothbrush with a single-core processor to collect raw data in a real-time scenario, eliminating the manual transfer of powered toothbrush data with mobile health applications. Associating powered toothbrush with a single-core processor is believed to provide reliable and comprehensible data of toothbrush use and propensities can be a guide to improve individual exhortation and general plans on oral hygiene quantifies that can prompt improved oral wellbeing. The method makes a case for an expanded chance to plan assistant capacities to protect or improve factors that influence oral wellbeing in individuals with mild cognitive impairment. The proposed framework assists with determining various parameters, which makes it adaptable and conceivable to execute in various oral care contexts 

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    ICMHI-OKA
  • 2.
    Ahmadi Mehri, Vida
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    An Investigation of CPU utilization relationship between host and guests in a Cloud infrastructure2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Cloud computing stands as a revolution in IT world in recent years. This technology facilitates resource sharing by reducing hardware costs for business users and promises energy efficiency and better resource utilization to the service providers. CPU utilization is a key metric considered in resource management across clouds.

    The main goal of this thesis study is directed towards investigating CPU utilization behavior with regard to host and guest, which would help us in understanding the relationship between them. It is expected that perception of these relationships would be helpful in resource management.

    Working towards our goal, the methodology we adopted is experi- mental research. This involves experimental modeling, measurements and observations from the results. The experimental setup covers sev- eral complex scenarios including cloud and a standalone virtualization system. The results are further analyzed for a visual correlation.

    Results show that CPU utilization in cloud and virtualization sce- nario coincides. More experimental scenarios are designed based on the first observations. The obtaining results show the irregular behav- ior between PM and VM in variable workload.

    CPU utilization retrieved from both cloud and a standalone system is similar. 100% workload situations showed that CPU utilization is constant with no correlation co-efficient obtained. Lower workloads showed (more/less) correlation in most of the cases in our correlation analysis. It is expected that more number of iterations can possibly vary the output. Further analysis of these relationships for proper resource management techniques will be considered. 

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    fulltext
  • 3.
    Ammar, Doreid
    et al.
    Norwegian Univ Sci & Technol, NOR.
    De Moor, Katrien
    Norwegian Univ Sci & Technol, NOR.
    Xie, Min
    Next Generat Serv, Telenor Res, NOR.
    Fiedler, Markus
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Heegaard, Poul
    Norwegian Univ Sci & Technol, NOR.
    Video QoE Killer and Performance Statistics in WebRTC-based Video Communication2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we investigate session-related performance statistics of a Web-based Real-Time Communication (WebRTC) application called appear. in. We explore the characteristics of these statistics and explore how they may relate to users' Quality of Experience (QoE). More concretely, we have run a series of tests involving two parties and according to different test scenarios, and collected real-time session statistics by means of Google Chrome's WebRTC-internals tool. Despite the fact that the Chrome statistics have a number of limitations, our observations indicate that they are useful for QoE research when these limitations are known and carefully handled when performing post-processing analysis. The results from our initial tests show that a combination of performance indicators measured at the sender's and receiver's end may help to identify severe video freezes (being an important QoE killer) in the context of WebRTC-based video communication. In this paper the performance indicators used are significant drops in data rate, non-zero packet loss ratios, non-zero PLI values, and non-zero bucket delay.

  • 4.
    Ayyagari, Nitin Reddy
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Databases For Mediation Systems: Design and Data scaling approach2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Context: There is continuous growth in data generation due to wide usage of modern communication systems. Systems have to be designed which can handle the processing of these data volumes efficiently. Mediation systems are meant to serve this purpose. Databases form an integral part of the mediation systems. Suitability of the databases for such systems is the principle theme of this work.

    Objectives: The objective of this thesis is to identify the key requirements for databases that can be used as part of Mediation systems, gain a thorough understanding of various features, the data models commonly used in databases and to benchmark their performance.

    Methods: Previous work that has been carried out on various databases is studied as a part of literature review. Test bed is set up as a part of experiment and performance metrics such as throughput and total time taken were measured through a Java based client. Thorough analysis has been carried out by varying various parameters like data volumes, number of threads in the client etc.

    Results: Cassandra has a very good write performance for event and batch operations. Cassandra has a slightly better read performance when compared to MySQL Cluster but this differentiation withers out in case of fewer number of threads in the client.

    Conclusions: On evaluation of MySQL Cluster and Cassandra we conclude that they have several features that are suitable for mediation systems. On the other hand, Cassandra does not guarantee ACID transactions while MySQL Cluster has good support. There is need for further evaluation on new generation databases which are not mature enough as of now.

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  • 5.
    Bjorklund, Svante
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Johansson, Tommy
    Swedish Def Res Agcy FOI, SE-58111 Linkoping, Sweden..
    Petersson, Henrik
    Swedish Def Res Agcy FOI, SE-58111 Linkoping, Sweden..
    Target Classification in Perimeter Protection with a Micro-Doppler Radar2016Ingår i: 2016 17TH INTERNATIONAL RADAR SYMPOSIUM (IRS), 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    In security surveillance at the perimeter of critical infrastructure, such as airports and power plants, approaching objects have to be detected and classified. Especially important is to distinguish between humans, animals and vehicles. In this paper, micro-Doppler data (from movement of internal parts of the target) have been collected with a small radar of a low complexity and cost-effective type. From time-velocity diagrams of the data, some physical features have been extracted and used in a support vector machine classifier to distinguish between the classes "human", "animal" and "man-made object". Both the type of radar and the classes are suitable for perimeter protection. The classification result are rather good, 77% correct classification. Particularly interesting is the surprisingly good ability to distinguish between humans and animals. This also indicates that we can choose to have limitations in the radar and still solve the classification task.

  • 6.
    Bjorklund, Svante
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Petersson, Henrik
    Swedish Def Res Agcy FOI, SE-58111 Linkoping, Sweden..
    Hendeby, Gustaf
    Swedish Def Res Agcy FOI, SE-58111 Linkoping, Sweden.;Linkoping Univ, SE-58183 Linkoping, Sweden..
    Features for micro-Doppler based activity classification2015Ingår i: IET radar, sonar & navigation, ISSN 1751-8784, E-ISSN 1751-8792, Vol. 9, nr 9, s. 1181-1187Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Safety and security applications benefit from better situational awareness. Radar micro-Doppler signatures from an observed target carry information about the target's activity, and have potential to improve situational awareness. This article describes, compares, and discusses two methods to classify human activity based on radar micro-Doppler data. The first method extracts physically interpretable features from the time-velocity domain such as the main cycle time and properties of the envelope of the micro-Doppler spectra and use these in the classification. The second method derives its features based on the components with the most energy in the cadence-velocity domain (obtained as the Fourier transform of the time-velocity domain). Measurements from a field trial show that the two methods have similar activity classification performance. It is suggested that target base velocity and main limb cadence frequency are indirect features of both methods, and that they do often alone suffice to discriminate between the studied activities. This is corroborated by experiments with a reduced feature set. This opens up for designing new more compact feature sets. Moreover, weaknesses of the methods and the impact of non-radial motion are discussed.

  • 7.
    Björklund, Svante
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Grahn, Per
    Nelander, Anders
    Pettersson, Mats
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Measurement of Rank and Other Properties of Direct and Scattered Signals2016Ingår i: International Journal of Antennas and Propagation, ISSN 1687-5869, E-ISSN 1687-5877, Vol. 2016, artikel-id 5483547Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We have designed an experiment for low-cost indoor measurements of rank and other properties of direct and scattered signals with radar interference suppression in mind. The signal rank is important also in many other applications, for example, DOA (Direction of Arrival) estimation, estimation of the number of and location of transmitters in electronic warfare, and increasing the capacity in wireless communications. In real radar applications, such measurements can be very expensive, for example, involving airborne radars with array antennas. We have performed the measurements in an anechoic chamber with several transmitters, a receiving array antenna, and a moving reflector. Our experiment takes several aspects into account: transmitted signals with different correlation, decorrelation of the signals during the acquisition interval, covariance matrix estimation, noise eigenvalue spread, calibration, near-field compensation, scattering in a rough surface, and good control of the influencing factors. With our measurements we have observed rank, DOA spectrum, and eigenpatterns of direct and scattered signals. The agreement of our measured properties with theoretic and simulated results in the literature shows that our experiment is realistic and sound. The detailed description of our experiment could serve as help for conducting other well-controlled experiments. © Copyright 2016 Svante Björklund et al.

  • 8.
    Boldt, Martin
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Ickin, Selim
    Ericsson Research, SWE.
    Borg, Anton
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Kulyk, Valentin
    Ericsson Research, SWE.
    Gustafsson, Jörgen
    Ericsson Research, SWE.
    Alarm prediction in cellular base stations using data-driven methods2021Ingår i: IEEE Transactions on Network and Service Management, E-ISSN 1932-4537, Vol. 18, nr 2, s. 1925-1933Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The importance of cellular networks continuously increases as we assume ubiquitous connectivity in our daily lives. As a result, the underlying core telecom systems have very high reliability and availability requirements, that are sometimes hard to meet. This study presents a proactive approach that could aid satisfying these high requirements on reliability and availability by predicting future base station alarms. A data set containing 231 internal performance measures from cellular (4G) base stations is correlated with a data set containing base station alarms. Next, two experiments are used to investigate (i) the alarm prediction performance of six machine learning models, and (ii) how different predict-ahead times (ranging from 10 min to 48 hours) affect the predictive performance. A 10-fold cross validation evaluation approach and statistical analysis suggested that the Random Forest models showed best performance. Further, the results indicate the feasibility of predicting severe alarms one hour in advance with a precision of 0.812 (±0.022, 95 % CI), recall of 0.619 (±0.027) and F1-score of 0.702 (±0.022). A model interpretation package, ELI5, was used to identify the most influential features in order to gain model insight. Overall, the results are promising and indicate the potential of an early-warning system that enables a proactive means for achieving high reliability and availability requirements. IEEE

  • 9.
    Chadalapaka, Gayatri
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik. BTH.
    Performance Assessment of Spectrum Sharing Systems: with Service Differentiation2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
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    BTH2018Chadalapaka
  • 10. Chandu, Chiranjeevi
    Region of Interest Aware and Impairment Based Image Quality Assessment2016Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
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    BTH2016Chiranjeevi
  • 11.
    Chu, Thi My Chin
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kreativa teknologier.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kreativa teknologier.
    On Capacity of Full-Duplex Cognitive Cooperative Radio Networks with Optimal Power Allocation2017Ingår i: 2017 IEEE WIRELESS COMMUNICATIONS AND NETWORKING CONFERENCE (WCNC), IEEE , 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we examine a full-duplex transmission scheme for cognitive cooperative radio networks (CCRNs) to improve capacity. In this network, the secondary transmitter and secondary relay are allowed to utilize the licensed spectrum of the primary user by using underlay spectrum access. We assume that the CCRN is subject to the interference power constraint of the primary receiver and maximum transmit power limit of the secondary transmitter and secondary relay. Under these constraints, we propose an optimal power allocation policy for the secondary transmitter and the secondary relay based on average channel state information (CSI) to optimize capacity. Then, we derive an expression for the corresponding achievable capacity of the secondary network over Nakagami-m fading. Numerical results are provided for several scenarios to study the achievable capacity that can be offered by this full-duplex underlay CCRN using the proposed optimal power allocation scheme.

  • 12.
    Chu, Thi My Chinh
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Zepernick, Hans-Juergen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Modeling and Analysis of Small Cell Networks with NOMA: A Stochastic Geometry Approach2021Ingår i: IEEE ICCE 2020: 2020 IEEE EIGHTH INTERNATIONAL CONFERENCE ON COMMUNICATIONS AND ELECTRONICS (ICCE), IEEE , 2021, s. 105-110Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, a stochastic geometry approach is used to model and analyse a downlink small cell network (SCN). Carrier sense multiple access with collision avoidance (CSMA/CA) is used as medium access control (MAC) protocol at the base stations (BSs). To boost spectral efficiency, each active BS deploys both orthogonal multiple access (OMA) and nonorthogonal multiple access (NOMA) to transmit signals to the user equipments (UEs) in its coverage area. The choice between OMA and NOMA mode is based on the density of UEs and aims to improve the sum rate of the BS. If there exist two UEs that sufficiently differ in their channel power gains to the BS, the BS will use NOMA superimposing the signals of the UEs in the power-domain. Otherwise, the BS will operate in OMA mode to transmit the signal of a single UE in its coverage area. Stochastic geometry is used to include the spatial densities of the UEs and BSs in the performance assessment of the SCN. On this basis, analytical expressions for the coverage probability, data rates of the UEs, and sum rate of the BSs of the considered system are derived. Numerical results are provided to illustrate the impact of system parameters on the performance of this SCN with NOMA subject to the spatial densities of the BSs and UEs.

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    fulltext
  • 13.
    Chu, Thi My Chinh
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Zepernick, Hans-Juergen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Hook, Anders
    Saab AB, Surveillance, Gothenburg, Sweden.
    Westerhagen, Alexander
    Saab AB, Surveillance, Karlskrona, Sweden.
    Granbom, Bo
    Saab AB, Aeronautics, Linkoping.
    OTFS Modulation for Non-Terrestrial Networks: Concepts, Applications, Benefits, and Challenges2023Ingår i: 2023 16th International Conference on Signal Processing and Communication System, ICSPCS 2023 - Proceedings / [ed] Wysocki B.J., Wysocki T.A., IEEE, 2023Konferensbidrag (Refereegranskat)
    Abstract [en]

    Fifth generation (5G), beyond 5G (B5G), and future sixth generation (6G) mobile networks are foreseen to increasingly account for heterogeneous networks toward ubiquitous communications with non-terrestrial networks (NTNs). Furthermore, in 5G mobile networks, massive machine type communications has been introduced for Internet of Things (IoT) applications aiming at low energy consumption, low to medium data rates, burst transmissions, and massive connectivity. It is expected that IoT communications will take an even larger portion in B5G and 6G mobile networks. Robust communications in such high-mobility NTN deployments including unmanned aerial vehicles (UAVs), airborne platforms, and satellite systems, need novel modulation waveforms that can deal with the induced severe Doppler effects. Orthogonal time frequency space (OTFS) modulation has gained tremendous interest in recent years as an effective technology for coping with high Doppler channels. OTFS essentially transforms a time-varying fading channel into a quasi-static channel in the delay-Doppler domain. In this paper, for the first time, an overview on OTFS modulation for NTNs is provided including basic concepts and applications in UAVs, airborne networks, and satellite systems. A case study related to an application in high Doppler airborne communication networks is also provided to illustrate the potential of OTFS modulation in providing robust transmission links in high-mobility scenarios. This survey will be helpful for researchers and practitioners to keep abreast about the potential of OTFS modulation in NTNs. © 2023 IEEE.

  • 14.
    Chu, Thi My Chinh
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Phan, Hoc
    Univ Reading, GBR.
    Hybrid spectrum access with relay assisting both primary and secondary networks under imperfect spectrum sensing2016Ingår i: EURASIP Journal on Wireless Communications and Networking, ISSN 1687-1472, E-ISSN 1687-1499, artikel-id 244Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper proposes a novel hybrid interweave-underlay spectrum access for a cognitive amplify-and-forward relay network where the relay forwards the signals of both the primary and secondary networks. In particular, the secondary network (SN) opportunistically operates in interweave spectrum access mode when the primary network (PN) is sensed to be inactive and switches to underlay spectrum access mode if the SN detects that the PN is active. A continuous-time Markov chain approach is utilized to model the state transitions of the system. This enables us to obtain the probability of each state in the Markov chain. Based on these probabilities and taking into account the impact of imperfect spectrum sensing of the SN, the probability of each operation mode of the hybrid scheme is obtained. To assess the performance of the PN and SN, we derive analytical expressions for the outage probability, outage capacity, and symbol error rate over Nakagami-m fading channels. Furthermore, we present comparisons between the performance of underlay cognitive cooperative radio networks (CCRNs) and the performance of the considered hybrid interweave-underlay CCRN in order to reveal the advantages of the proposed hybrid spectrum access scheme. Eventually, with the assistance of the secondary relay, performance improvements for the PN are illustrated by means of selected numerical results.

  • 15.
    Chu, Thi My Chinh
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Phan, Hoc
    Duy Tan Univ, VNM.
    Optimal Secrecy Capacity of Underlay Cognitive Radio Networks with Multiple Relays2016Ingår i: MILCOM 2016 - 2016 IEEE MILITARY COMMUNICATIONS CONFERENCE, 2016, s. 162-167Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we study the secrecy capacity of an underlay cooperative cognitive radio network (CCRN) where multiple relays are deployed to assist the secondary transmission. An optimal power allocation algorithm is proposed for the secondary transmitter and secondary relays to obtain the maximum secrecy capacity while satisfy the interference power constraint at the primary receiver and the transmit power budget of the CCRN. Since the optimization problem for the secrecy capacity is non-convex, we utilize an approximation and fitting method to convert the optimization problem into a geometric programming problem which then is solved by applying the Logarithmic barrier function. Numerical results are provided to study the effect of network parameters on the secrecy capacity. Through the numerical results, the advantage of the proposed power allocation algorithm compared to equal power allocation can also be observed.

  • 16.
    Ekramian, Elnaz
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Automation of the test methods for packet loss and packet loss duration in the Ixia platform2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Today’s technology has a strong tendency towards automation. As a matter of fact, the tremendous improvement of science in the recent years brought new ideas regarding to accelerate the scientific process that is not separated of automation. This paper also deals with automation of manual tests that were used to analyze packet loss and packet loss duration in a network. These two metrics were chosen based on their importance they have in the communication technology, also based on the weak points that were found in the manual processes. This experiment is done in the Ixia platform that was an appropriate test bed to design an automation framework.After a comprehensive research on network and communication we could choose packet loss and packet loss duration as two important parameters that are under test several times per day. Therefore, based on the properties that are used for automation, these two metrics had the priority compare to other metrics. We could create a framework that works correspond to the manual test process. For this purpose, Tcl programming language is used. The script that was written with this high-level language can communicate with the graphical user interface, configuring all the connected devices, measuring mentioned metrics and ultimately save the result in a csv file.Finally, we could reach to the main objective of this project which was to show how positively automatic method can affect on the quality of test in terms of accuracy, time and manpower saving.

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  • 17.
    Fakhouri, Hussam N.
    et al.
    University of Petra, Jordan.
    Alawadi, Sadi
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Awaysheh, Feras M.
    Tartu University, Estonia.
    Hani, Imad Bani
    Halmstad University.
    Alkhalaileh, Mohannad
    Al Ain University, United Arab Emirates.
    Hamad, Faten
    Sultan Qaboos University, Oman.
    A Comprehensive Study on the Role of Machine Learning in 5G Security: Challenges, Technologies, and Solutions2023Ingår i: Electronics, E-ISSN 2079-9292, Vol. 12, nr 22, artikel-id 4604Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fifth-generation (5G) mobile networks have already marked their presence globally, revolutionizing entertainment, business, healthcare, and other domains. While this leap forward brings numerous advantages in speed and connectivity, it also poses new challenges for security protocols. Machine learning (ML) and deep learning (DL) have been employed to augment traditional security measures, promising to mitigate risks and vulnerabilities. This paper conducts an exhaustive study to assess ML and DL algorithms’ role and effectiveness within the 5G security landscape. Also, it offers a profound dissection of the 5G network’s security paradigm, particularly emphasizing the transformative role of ML and DL as enabling security tools. This study starts by examining the unique architecture of 5G and its inherent vulnerabilities, contrasting them with emerging threat vectors. Next, we conduct a detailed analysis of the network’s underlying segments, such as network slicing, Massive Machine-Type Communications (mMTC), and edge computing, revealing their associated security challenges. By scrutinizing current security protocols and international regulatory impositions, this paper delineates the existing 5G security landscape. Finally, we outline the capabilities of ML and DL in redefining 5G security. We detail their application in enhancing anomaly detection, fortifying predictive security measures, and strengthening intrusion prevention strategies. This research sheds light on the present-day 5G security challenges and offers a visionary perspective, highlighting the intersection of advanced computational methods and future 5G security. © 2023 by the authors.

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  • 18.
    Fiedler, Markus
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Chapala, Usha Kiran
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Peteti, Sridhar
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Modeling instantaneous quality of experience using machine learning of model trees2019Ingår i: 2019 11th International Conference on Quality of Multimedia Experience, QoMEX 2019, Institute of Electrical and Electronics Engineers Inc. , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    For service providers and operators, successful root cause analysis is essential for satisfactory service provisioning. However, reasons for sudden trend changes of the instantaneous Quality of Experience (QoE) may not always be immediately visible from underlying service- or network-level monitoring data. Thus, there is the challenge to pinpoint such moments of change in provisioning, and model the impact on instantaneous QoE, as a lead in root cause analysis. This work investigates the potential of Machine Learning (ML) of deriving time-interval-based models for instantaneous QoE ratings, obtained from a set of publicly available rating traces. In particular, the paper demonstrates the capability of the ML algorithm M5P to model trends of instantaneous QoE through model trees, consisting of piecewise linear functions over time. It is shown how and to which extent these functions can be used to estimate moments of change. Furthermore, the model trees support earlier assumptions about exponential shapes of instantaneous QoE over time as reactions to sudden changes of provisioning, such as video freezes. © 2019 IEEE.

  • 19.
    Fiedler, Markus
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    De Moor, Katrien
    Norwegian University of Science and Technology, NOR.
    Ravuri, Hemanth
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Tanneedi, Prithvi
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Chandiri, Mounika
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Users On The Move: On Relationships Between QoE Ratings, Data Volumes and Intentions to Churn2017Ingår i: Proc. 2017 IEEE 42nd Conference on Local Computer Networks Workshops (LCN Workshops): Workshop On User MObility and VEhicular Networks (ON-MOVE), IEEE, 2017, s. 97-102Konferensbidrag (Refereegranskat)
    Abstract [en]

    For a long time, the risk of customer churn, i.e. to leave an operator, has been used as argument in favor of Quality of Experience (QoE) research. However, the understanding of how churn behavior and QoE are related is still limited. This is problematic, as customer retention and churn prediction have grown in importance in face of ever-growing competition on the telecom market. The work presented in this paper aims to make a contribution in this respect, by exploring the relationships between QoE ratings, data volumes and churn risk through a longitudinal user study. Using an Experience Sampling Method-inspired approach we have been collecting weekly feedback on experienced quality, annoyance and intentions to churn from 22 users for up to eight weeks. Additionally, measurements of weekly used data volumes were collected. We observed churning behavior for 3 out of 22 participants and analyze the rating and data usage profiles of churners against non-churners. Furthermore, we investigate correlations of ratings and volumes, and find that “annoyed churners surf less”. Our findings point out warning signals for potential user churn as well as promising directions for future studies.

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  • 20.
    Fiedler, Markus
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Zepernick, Hans-Juergen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Kelkkanen, Viktor
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Network-induced temporal disturbances in virtual reality applications2019Ingår i: 2019 11th International Conference on Quality of Multimedia Experience, QoMEX 2019, Institute of Electrical and Electronics Engineers Inc. , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Virtual Reality (VR) applications put high demands on software and hardware in order to enable an immersive experience for the user and avoid causing simulator sickness. As soon as networks become part of the Motion-To-Photon (MTP) path between rendering and display, there is a risk for extraordinary delays that may impair Quality of Experience (QoE). This short paper provides an overview of latency measurements and models that are applicable to the MTP path, complemented by demands on user and network levels. It specifically reports on freeze duration measurements using a commercial TPCAST wireless VR solution, and identifies a corresponding stochastic model of the freeze length distribution, which may serve as disturbance model for VR QoE studies. © 2019 IEEE.

  • 21. Garcia Armada, Ana
    et al.
    Nogueira, Michele
    Saha, Dola
    Coleri, Sinem
    Tutschku, Kurt Tutschku
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik. Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Horner, Larry
    He, Yuwen
    Ma, Liangping
    Chowdhry, Bhawani S.
    GLOBAL COMMUNICATIONS NEWSLETTER: Conference Report: IEEE NFV-SDN 2019 in Dallas, TX, USA.2020Ingår i: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 58, nr 5, s. 13-16Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
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  • 22.
    Geremew, Getahun Wassie
    et al.
    Addis Ababa University, Ethiopia.
    Ding, Jianguo
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Elephant Flows Detection Using Deep Neural Network, Convolutional Neural Network, Long Short-Term Memory, and Autoencoder2023Ingår i: Journal of Computer Networks and Communications, ISSN 2090-7141, E-ISSN 2090-715X, Vol. 2023, artikel-id 1495642Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Currently, the widespread of real-time applications such as VoIP and videos-based applications require more data rates and reduced latency to ensure better quality of service (QoS). A well-designed traffic classification mechanism plays a major role for good QoS provision and network security verification. Port-based approaches and deep packet inspection (DPI) techniques have been used to classify and analyze network traffic flows. However, none of these methods can cope with the rapid growth of network traffic due to the increasing number of Internet users and the growth of real-time applications. As a result, these methods lead to network congestion, resulting in packet loss, delay, and inadequate QoS delivery. Recently, a deep learning approach has been explored to address the time-consumption and impracticality gaps of the abovementioned methods and maintain existing and future traffics of real-time applications. The aim of this research is then to design a dynamic traffic classifier that can detect elephant flows to prevent network congestion. Thus, we are motivated to provide efficient bandwidth and fast transmission requirements to many Internet users using SDN capability and the potential of deep learning. Specifically, DNN, CNN, LSTM, and Deep autoencoder are used to build elephant detection models that achieve an average accuracy of 99.12%, 98.17%, and 98.78%, respectively. Deep autoencoder is also one of the promising algorithms that do not require human class labeler. It achieves an accuracy of 97.95% with a loss of 0.13. Since the loss value is closer to zero, the performance of the model is good. Therefore, the study has a great importance to Internet service providers, Internet subscribers, as well as for future researchers in this area.

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  • 23.
    Gharari, Farnaz
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Chu, Thi My Chinh
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Performance Analysis of a Piecewise-and-Forward Relay Network on Rayleigh Fading Channels2015Ingår i: 2015 9TH INTERNATIONAL CONFERENCE ON SIGNAL PROCESSING AND COMMUNICATION SYSTEMS (ICSPCS), IEEE Communications Society, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we analyse the performance of a cooperative communication network with multiple piecewise-and-forward (PF) relays on Rayleigh fading channels taking the random nature of the channel variations into account. In particular, the probability density function (PDF) of the received signals at the destination of the considered multiple PF relay network is derived for the case of Rayleigh fading. The PDF is then used to support the maximum likelihood detection at the destination. Simulation results are provide to compare the bit error rate (BER) performance of the PF protocol in a multiple relay network with the performance of the amplify-and-forward (AF), decode-and-forward (DF), and estimate-and-forward (EF) protocols on Rayleigh fading as well as additive white Gaussian noise (AWGN) channels. The results indicate that the PF protocol outperforms the EF protocol in the low signal-to-noise ratio (SNR) regime while it is slightly inferior to the EF protocol for high SNR. This behavior is more pronounced over Rayleigh fading compared to AWGN.

  • 24. Han, Guangjie
    et al.
    Shen, Wen
    Duong, Trung Q.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Guizani, Mohsen
    Hara, Takahiro
    A proposed security scheme against Denial of Service attacks in cluster-based wireless sensor networks2014Ingår i: SECURITY AND COMMUNICATION NETWORKS, ISSN 1939-0114, Vol. 7, nr 12, s. 2542-2554Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Traditional security schemes developed for sensor networks are not suitable for cluster-based wireless sensor networks (WSNs) because of their susceptibility to Denial of Service (DoS) attacks. In this paper, we provide a security scheme against DoS attacks (SSAD) in cluster-based WSNs. The scheme establishes trust management with energy character, which leads nodes to elect trusted cluster heads. Furthermore, a new type of vice cluster head node is proposed to detect betrayed cluster heads. Theoretical analyses and simulation results show that SSAD can prevent and detect malicious nodes with high probability of success

  • 25. Hellisten, Hans
    et al.
    Machado, Renato
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Pettersson, Mats I.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Vu, Viet Thuy
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för matematik och naturvetenskap.
    Dammert, Patrik
    EXPERIMENTAL RESULTS ON CHANGE DETECTION BASED ON BAYES PROBABILITY THEOREM2015Ingår i: 2015 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM (IGARSS), IEEE Communications Society, 2015, s. 318-321Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we propose a new change detection (CD) algorithm based on the Bayes theorem and probability assignments. Differently from any kind of likelihood ratio test (LRT) algorithms, the proposed algorithm does not present target alarms, but the probability of certain image position is a target position. In other words, the proposed method leads to quantitative estimates on the probability of a target at any pixel, whereas LRT algorithms can only be used as a figure of merit for any pixel to contain a target.

  • 26.
    Horner, Larry J.
    et al.
    Intel.
    Tutschku, Kurt
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Fumagalli, Andrea
    University of Texas, USA.
    Virtualizing 5G and Beyond 5G Mobile Network2023Bok (Övrigt vetenskapligt)
    Abstract [en]

    The fifth generation (5G) mobile network brings significant new capacity and opportunity to network operators while also creating new challenges and additional pressure to build and operate networks differently. The transformation to 5G mobile networks creates the opportunity to virtualize significant portions of the radio access (RAN) and network core, allowing operators to better compete with over-the-top and hyperscaler offerings. This book covers the business and technical areas of virtualization that enable the transformation and innovation that today’s operators are seeking. It identifies forward-looking gaps where the technology continues to develop, specifically packet acceleration and timing requirements, which today are still not fully virtualized. The book shows you the operational and support considerations, development and lifecycle management, business implications, and vendor-team dynamics involved in deploying a virtualized network. Packed with key concepts of virtualization that solve a broad array of problems, this is an essential reference for those entering this technical domain, those that are going to build and operate these networks, and those that are seeking to learn more about the telecom network. It illustrates why you just can’t do it all in the cloud today.

  • 27. Hossfeld, Tobias
    et al.
    Fiedler, Markus
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    The unexpected QoE killer: When the network emulator misshapes traffic and QoE2015Ingår i: 2015 7th International Workshop on Quality of Multimedia Experience, QoMEX 2015, IEEE Communications Society, 2015, Vol. Article number 7148093Konferensbidrag (Refereegranskat)
    Abstract [en]

    Packet streams observed in today’s networks show a high degree of autocorrelation as successive packets tend to exhibit similar delay and loss characteristics. Network emulators used to conduct performance evaluations therefore have to support the generation of such autocorrelated streams. Typically, this is done using first order autoregressive processes. In this paper, we show that a common implementation of this approach leads to problems when emulating correlated packet loss, and therefore possibly produces erroneous results and conclusions when evaluating objectively application quality or QoE in subjective studies. Further typical network emulator implementations make even low packet jitter become an unexpected QoE killer. © 2015 IEEE.

  • 28.
    Hu, Yan
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Elwardy, Majed
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Zepernick, Hans-Juergen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    On the Effect of Standing and Seated Viewing of 360 degrees Videos on Subjective Quality Assessment2020Ingår i: 2020 IEEE CONFERENCE ON VIRTUAL REALITY AND 3D USER INTERFACES WORKSHOPS (VRW 2020), IEEE COMPUTER SOC , 2020, s. 285-286Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we compare the impact that standing and seated viewing of 360 degrees videos on head-mounted displays has on subjective quality assessment. The statistical analysis of the data gathered in a pilot study is reported in terms of average rating times, mean opinion scores, and simulator sickness scores. The results indicate: (1) Average rating times consumed for 360 degrees video quality assessment are similar for standing and seated viewing, (2) Higher resolving power among different quality levels is obtained for seated viewing, (3) Simulator sickness is kept significantly lower when seated.

  • 29.
    Ilie, Dragos
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Datta, Vishnubhotla Venkata Krishna Sai
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    On Designing a Cost-Aware Virtual CDN for the Federated Cloud2016Ingår i: 2016 INTERNATIONAL CONFERENCE ON COMMUNICATIONS (COMM 2016), IEEE, 2016, s. 255-260Konferensbidrag (Refereegranskat)
    Abstract [en]

    We have developed a prototype for a cost-aware, cloud-based content delivery network (CDN) suitable for a federated cloud scenario. The virtual CDN controller spawns and releases virtual caching proxies according to variations in user demand. A cost-based heuristic algorithm is used for selecting data centers where proxies are spawned. The functionality and performance of our virtual CDN prototype were evaluated in the XIFI federated OpenStack cloud. Initial results indicate that the virtual CDN can offer reliable and prompt service. Multimedia providers can use this virtual CDN solution to regulate expenses and have greater freedom in choosing the placement of virtual proxies as well as more flexibility in configuring the hardware resources available to the proxy (e.g., CPU cores, memory and storage).

  • 30.
    Ilie, Dragos
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Grahn, Håkan
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Lundberg, Lars
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Westerhagen, Alexander
    Saab AB, Surveillance.
    Topology Control for Directed DataLinks between Airborne Platforms: Directed Air Data Link: WP3 report2023Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Contemporary airborne radio networks are usually implemented using omnidirectional antennas. Unfortunately, such networks suffer from disadvantages such as easy detection by hostile aircraft and potential information leakage. In addition, tactical links used for military communication rely on NATO-specific standards such as Link 16, which are becoming outdated. 

    To this end we are investigating the feasibility of replacing omnidirectional communication with directed communication, which will address the disadvantages mentioned above. In addition, we definine a communication architecture based on the conventional Ethernet and TCP/IP protocol stack, which will ease management and interoperability with existing Internet-based system 

    In this report, we briefly review the TCP/IP stack and the services offerd at each layer of the stack. Furthermore, we review existing litterature involving mobile ad hoc network (MANET) protocols used for airborne networks along with various performance studies in the same area. Finally, we propose a novel MANET routing protocol based on directional antennas and situation awareness data that utilizes adaptive multihop routing to avoid sending information in directions where hostile nodes are present. 

    Our protocol is implemented in the OMNEST simulator and evaluated using two realistic flight scenarios involving 8 and 24 aircraft, respectively. The results show that our protocol has significantly fewer leaked packets than comparative protocols, but at a slightly higher cost in terms of longer packet lifetime. 

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  • 31.
    Iqbal, Muhammad Imran
    et al.
    Axis Communications AB, SWE.
    Zepernick, Hans-Juergen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Error sensitivity analysis of DMB transport streams2019Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 7, s. 154424-154434, artikel-id 8876649Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we examine the sensitivity of the digital multimedia broadcasting (DMB) MPEG-2 transport stream (TS) format to transmission errors. To find the sensitivity of different parts of TS packets to transmission errors, each TS packet is divided into four cells, i.e., the first three cells comprising 48 bytes each and the last cell is of 44 bytes length. Bit errors are then introduced into these different parts of the TS packets. The sensitivity of DMB videos to transmission errors and their locations is assessed in terms of the following measures: 1) Number of decoder crashes; 2) Number of decodable videos; 3) Total number of decodable frames; and 4) Objective perceptual video quality of the decoded videos. The structural similarity index and visual information fidelity criterion are used as objective perceptual quality metrics. Simulations are performed on seven different DMB videos using various bit error rates. The results show that the first cell of the TS packets is highly sensitive to bit errors compared to the subsequent three cells, both in terms of spatial and temporal video quality. Further, the sensitivity decreases from Cell 1 to Cell 4 of a DMB TS packet. The error sensitivity analysis reported in this paper may guide the development of more reliable transmission systems for future DMB systems and services. Specifically, the insights gained from this study may support designing better error control schemes that take the sensitivity of different parts of DMB TS packets into consideration.

  • 32.
    Irshad, Azeem
    et al.
    Int. Islamic Univ., PAK.
    Sher, Muhammad
    Int. Islamic Univ., PAK.
    Nawaz, Omer
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Chaudhry, Shehzad Ashraf
    Int. Islamic Univ., PAK.
    Khan, Imran
    Int. Islamic Univ., PAK.
    Kumari, Saru
    Chaudhary Charan Singh Univ, IND.
    A secure and provable multi-server authenticated key agreement for TMIS based on Amin et al. scheme2017Ingår i: Multimedia tools and applications, ISSN 1380-7501, E-ISSN 1573-7721, Vol. 76, nr 15, s. 16463-16489Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The security for Telecare Medicine Information Systems (TMIS) has been crucial for reliable dispensing of the medical services to patients at distant locations. Security and privacy element needs to be there for any physician or caregiver to make certain an appropriate diagnosis, medical treatment or any other exchange of critical information. In this connection, many relevant TMIS-based authentication schemes have been presented, however various forms of attacks and inefficiencies render these schemes inapplicable for a practical scenario. Lately, Amin et al. proposed a scheme based on a multi-server authentication for TMIS. However, the Amin et al., scheme has been found vulnerable to user and server impersonation attacks. We have proposed an improved model with higher performance and efficiency, as evident from the forthcoming sections. Besides, the scheme has been backed up by formal security analysis using BAN logic to ensure the resilience of the proposed scheme.

  • 33.
    Jamil, Momin
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Sequence Design for Radar Applications Using Particle Swarm Optimization2016Ingår i: PROCEEDINGS OF THE 2016 INTERNATIONAL CONFERENCE ON ADVANCED TECHNOLOGIES FOR COMMUNICATIONS (ATC), IEEE, 2016, s. 210-214Konferensbidrag (Refereegranskat)
    Abstract [en]

    Performance of polyphase sequences in radar applications can be evaluated using measures including autocorrelation function, integrated sidelobe ratio (ISLR), and peak-tosidelobe ratio (PSLR). In this paper, we adopt particle swarm optimization to find optimal parameters of Oppermann sequences such that sequences with optimal ISLR and PSLR are generated. This class of sequences has been chosen as it allows to design for a wide range of correlation characteristics by essentially controlling three parameters. A sequence design example is provided in order to illustrate that particle swarm optimization is indeed well-suited to produce optimal sequence designs with respect to the considered performance measures.

  • 34.
    Johari Varnoosfaderani, Mohammad
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Economical Debug Station For debugging 3G modem2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Communication world is growing with an incredible high speed. Every day comes new technologies and give us more access and opportunities in work and life.

    One of the most important branches is small cells and similar product families.

    It extends from a simple telegraph codes to 3G W-CDMA and 4G LTE networks.

    It offers mobile network operators a cost-effective alternative to macro-only deployments for meeting growing coverage and capacity demands.

    Making products and bring it to market is one part of the job. It is important that product be fault free and reliable. Due to this comes our need for test and debugging.

    Test and debugging have high value in massive production.

    This research is subjected to a small cell modem, this modem has different parts like:

    - Download link and upload link through fiber optic cables for CPRI.

    - Network part which include Wi-Fi and LAN.

    - GPS module.

    - eUSB for customization of modem firmware.

    - Com, I2C and JTAG ports for debugging or reprograming the modem.

    We need to develop a debug station to make debugging easier on this modem and having clear compare results. It is important to have a CPRI tester and GPS signal simulator in our debug station.

    Beside all of these we need to make free standalone debug station which save us money and time, and from other side it should be as accurate as possible which make it reliable.

    One of important tests which should get done on test object is Boundary scan in debug station.

    Debuggers mentioned that it is hard to stop the test process in each level and from other side it is hard to find the faults with pass/fail results.

    In this project we try to implement all necessary tests in one and same debug station.

    Debuggers use separate stations for function test and boundary scan test and eUSB programing, with help of this debug station we have all of these 3 main tests in same station and debugger can work independently to repair the boards without interfering in production process or waiting to get time to use function test station or boundary scan tester .

    One of the Results is saving time from debugger’s side and this is more effective for company to save money and give faster and better repair service.

    We should use calibrated and the most accurate tools for testing to get best result. 

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    BTH2016Johari
  • 35.
    Kabiri, Charles
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Sibomana, Louis
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Symbol Error Probability and Effective Capacity of an Underlay CRN over alpha-mu Fading Channels2015Ingår i: 2015 9TH INTERNATIONAL CONFERENCE ON SIGNAL PROCESSING AND COMMUNICATION SYSTEMS (ICSPCS), IEEE Communications Society, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper analyses the performance of an underlay cognitive radio network (CRN) over alpha-mu fading channels in terms of symbol error probability (SEP) and effective capacity (EC). The alpha-mu distribution allows for a more general fading model with an increased level of generality compared to well-known models such as Nakagami-m and Rayleigh fading. The SEP and EC at the secondary user receiver are therefore evaluated for different fading parameters alpha and mu In the considered underlay CRN, the secondary user transmit power is subject to a peak interference power constraint in order to limit the interference to the primary user receiver. Given this setting, analytical expressions for the SEP and EC are derived for the general case of alpha-mu fading channels. Numerical results are provided to illustrate the performance of the considered underlay CRN on different fading channels.

  • 36.
    Kabiri, Charles
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Tran, Hung
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Effective capacity of cognitive cooperative relay networks over α-μ Fading channels2015Ingår i: 2015 21st Asia-Pacific Conference on Communications, APCC 2015, IEEE Press, 2015, s. 427-432, artikel-id Article number 7412551Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, the effective capacity, a link-layer model supporting Quality of Service (QoS) metrics such as user data rate, packet loss rate and service delay, is analyzed. We consider an underlay cognitive cooperative relay network (CCRN) subject to independent non-identically distributed aH fading. An analytical expression of the effective capacity is derived by means of Fox H-functions and Meijer G-functions along with the Mellin transform of the product of two H-functions. The network performance is analyzed against the QoS exponent and the peak interference power constraint imposed by primary users.

  • 37.
    Kabiri, Charles
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Tran, Hung
    Malardalen Univ, SWE.
    Outage Probability of a Cognitive Cooperative Relay Network with Multiple Primary Users Under Primary Outage Constraint2016Ingår i: PROCEEDINGS OF THE 2016 INTERNATIONAL CONFERENCE ON ADVANCED TECHNOLOGIES FOR COMMUNICATIONS (ATC), IEEE, 2016, s. 38-42Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we consider a cognitive cooperative relay network (CCRN) that utilizes a decode-and-forward relay in the presence of multiple primary users. Given this system setting, we study the effect of multiple primary transmitters (PU-Txs) and multiple primary user receivers (PU-Rxs) on the outage probability of the considered CCRN. Specifically, power allocation policies for the secondary user transmitter (SU-Tx) and the secondary relay (SR) are formulated, subject to the outage constraint which is imposed by the PU-Rxs as well as the peak transmit power limits given at the SU-Tx and SR. On the basis of these power allocation policies for the SU-Tx and SR, an expression for the outage probability of the CCRN is derived. Numerical examples are presented to show the effect of different system parameters on the outage probability of the CCRN.

  • 38.
    Kastala, Emmanuel
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Zero Downtime Deployment approaches in Cloud Architecture - Efficiency of deployment process2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Our dependence on applications running cloud or server-based applications has increased exponentially over the last decade through easy access to computers and internet. Keeping web service running through updates and bug fixes is a challenge faced by the software development community. Hence, avoiding service interrupts and automating deployments have become more important now than before. This paper studies such deployment strategies for a web application. The objective of the thesis is to examine whether all three produce zero downtime during deployment and examine which deployment deploys a new service with the least amount of time. This study is done by deploying a new version of a web application on a cloud infrastructure during the application service is online and to check whether the service interrupts during the deployment of a new version. The study is carried out with two research methods: a Literature Review and experimentation. The goal of the Literature Review is to gain insights into the existing approaches and techniques and the second method aims to Experiment with selected approaches in a scenario, which will produce the result required to understand study area. The deployment strategies are the Blue-Green deployment strategy, canary deployment, and rolling deployment. Selected three approaches will be evaluated using the same resources, application, and environment. The results of the experiment show that none of the development strategies produce downtime of the service during the deployment process. The experiments result show that the Blue Green is faster than the Canary Deployment and Rolling deployment . Rolling deployment is faster than Canary deployment. Results show that one is faster than others and non produces non-zero downtime of services. This research will guide a developer to understand and pick the best deployment process for their software deployment process.

  • 39.
    Kebande, Victor R.
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Awaysheh, Feras M.
    Tartu University, EST.
    Ikuesan, Richard A.
    Community College Qatar, QAT.
    Alawadi, Sadi A.
    Uppsala University, SWE.
    Alshehri, Mohammad Dahman
    Taif University, SAU.
    A blockchain-based multi-factor authentication model for a cloud-enabled internet of vehicles2021Ingår i: Sensors, E-ISSN 1424-8220, Vol. 21, nr 18, artikel-id 6018Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Continuous and emerging advances in Information and Communication Technology (ICT) have enabled Internet-of-Things (IoT)-to-Cloud applications to be induced by data pipelines and Edge Intelligence-based architectures. Advanced vehicular networks greatly benefit from these architectures due to the implicit functionalities that are focused on realizing the Internet of Vehicle (IoV) vision. However, IoV is susceptible to attacks, where adversaries can easily exploit existing vulnerabilities. Several attacks may succeed due to inadequate or ineffective authentication techniques. Hence, there is a timely need for hardening the authentication process through cutting-edge access control mechanisms. This paper proposes a Blockchain-based Multi-Factor authentication model that uses an embedded Digital Signature (MFBC_eDS) for vehicular clouds and Cloud-enabled IoV. Our proposed MFBC_eDS model consists of a scheme that integrates the Security Assertion Mark-up Language (SAML) to the Single Sign-On (SSO) capabilities for a connected edge to cloud ecosystem. MFBC_eDS draws an essential comparison with the baseline authentication scheme suggested by Karla and Sood. Based on the foundations of Karla and Sood’s scheme, an embedded Probabilistic Polynomial-Time Algorithm (ePPTA) and an additional Hash function for the Pi generated during Karla and Sood’s authentication were proposed and discussed. The preliminary analysis of the proposition shows that the approach is more suitable to counter major adversarial attacks in an IoV-centered environment based on the Dolev–Yao adversarial model while satisfying aspects of the Confidentiality, Integrity, and Availability (CIA) triad. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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  • 40.
    Kebande, Victor R.
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Ikuesan, Richard Adeyemi
    Community College Qatar, QAT.
    Awaysheh, Feras M.
    Tartu University, EST.
    Alawadi, Sadi
    Uppsala University, SWE.
    Towards a Learning-enabled Virtual Sensor Forensic Architecture Compliant with Edge Intelligence2021Ingår i: 2021 2nd International Conference on Intelligent Data Science Technologies and Applications, IDSTA 2021 / [ed] Alsmirat M., Jararweh Y., Awaysheh F., Aloqaily, Institute of Electrical and Electronics Engineers Inc. , 2021, s. 154-161Konferensbidrag (Refereegranskat)
    Abstract [en]

    While the Internet of Things (IoT), Wireless Sensor Networks (WSNs), and the techniques for extracting digital data have seen continuous advancements, so does the cyber-Threat landscape. Virtual sensors which normally use abstraction layers that operate over a physical infrastructure to achieve their objectives, have seen rapid adoption, for example, it has aided in achieving manufacturing 4.0. This abstract layer has in the recent past seen tremendous proliferation within the sensor-based platform. Coupled with data pre-processing and key compliance with the guidelines for information security, incident investigation principles, and processes. This paper discusses a step towards a Learning-enabled (LE) Virtual Sensor Forensic (VSF) architecture that is compliant with edge intelligence technology, which is based on an initially proposed generic VSF architecture. Furthermore, apart from the learning capabilities, the LE-VSF architecture considers proactive and reactive investigation techniques by assuming an Internet of Vehicle (IoV) attack scenario, enhancing the reliability of a forensically sound data source. This proposition is essential in any sensor-based abstraction where the forensic analysis would otherwise be cumbersome and susceptible to noise. © 2021 IEEE.

  • 41.
    Kelkkanen, Viktor
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Fiedler, Markus
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    A Test-bed for Studies of Temporal Data Delivery Issues in a TPCAST Wireless Virtual Reality Set-up2018Ingår i: 2018 28TH INTERNATIONAL TELECOMMUNICATION NETWORKS AND APPLICATIONS CONFERENCE (ITNAC), IEEE , 2018, s. 404-406Konferensbidrag (Refereegranskat)
    Abstract [en]

    Virtual Reality (VR) is becoming increasingly popular, and wireless cable replacements unleash the user of VR Head Mounted Displays (HMD) from the rendering desktop computer. However, the price to pay for additional freedom of movement is a higher sensitivity of the wireless solution to temporal disturbances of both video frame and input traffic delivery, as compared to its wired counterpart. This paper reports on the development of a test-bed to be used for studying temporal delivery issues of both video frames and input traffic in a wireless VR environment, here using TPCAST with a HTC Vive headset. We provide a solution for monitoring and recording of traces of (1) video frame freezes as observed on the wireless VR headset, and (2) input traffic from the headset and hand controls to the rendering computer. So far, the test-bed illustrates the resilience of the underlying WirelesslID technology and TCP connections that carry the input traffic, and will be used in future studies of Quality of Experience (QoE) in wireless desktop VR.

  • 42.
    Kelkkanen, Viktor
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Fiedler, Markus
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Coefficient of Throughput Variation as Indication of Playback Freezes in Streamed Omnidirectional Videos2018Ingår i: 2018 28TH INTERNATIONAL TELECOMMUNICATION NETWORKS AND APPLICATIONS CONFERENCE (ITNAC), IEEE , 2018, s. 392-397Konferensbidrag (Refereegranskat)
    Abstract [en]

    A large portion of today's network traffic consists of streamed video of large variety, such as films, television shows, live-streamed games and recently omnidirectional videos. A common way of delivering video is by using Dynamic Adaptive Streaming over HTTP (DASH), or recently with encrypted HTTPS. Encrypted video streams disable the use of Quality of Service (QoS) systems that rely on knowledge of application-dependent data, such as video resolution and bit-rate. This could make it difficult for a party providing bandwidth to efficiently allocate resources and estimate customer satisfaction. An application-independent way of measuring video stream quality could be of interest for such a party. In this paper, we investigate encrypted streaming of omni-directional video via YouTube to a smartphone in a Google Cardboard VR-headset. We monitored such sessions, delivered via both WiFi and mobile networks, at different times of day, implying different levels of congestion, and characterised the network traffic by using the Coefficient of Throughput Variation (CoTV) as statistic. We observe that this statistic shows to be able to indicate whether a stream is stable or unstable, in terms of potential video playback freezes, when the DASH delivery strategy is used.

  • 43.
    Kelkkanen, Viktor
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Fiedler, Markus
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för teknik och estetik.
    Lindero, David
    Ericsson Research, SWE.
    Synchronous Remote Rendering for VR2021Ingår i: International Journal of Computer Games Technology, ISSN 1687-7047, E-ISSN 1687-7055, Vol. 2021, artikel-id 6676644Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Remote rendering for VR is a technology that enables high-quality VR on low-powered devices. This is realized by offloading heavy computation and rendering to high-powered servers that stream VR as video to the clients. This article focuses on one specific issue in remote rendering when imperfect frame timing between client and server may cause recurring frame drops. We propose a system design that executes synchronously and eliminates the aforementioned problem. The design is presented, and an implementation is tested using various networks and hardware. The design cannot drop frames due to synchronization issues but may on the other hand stall if temporal disturbances occur, e.g., due to network delay spikes or loss. However, experiments confirm that such events can remain rare given an appropriate environment. For example, remote rendering on an intranet at 90 fps with a server located approximately 50 km away yielded just 0.002% stalled frames while rendering with extra latency corresponding to the duration of exactly one frame (11.1 ms at 90 fps). In a LAN without extra latency setting, i.e., with latency equal to locally rendered VR, 0.009% stalls were observed while using a wired Ethernet connection and 0.058% stalls when using 5 GHz wireless IEEE 802.11 ac. © 2021 Viktor Kelkkanen et al.

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  • 44. Kim, Kyeong Jin
    et al.
    Duong, Trung Quang
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Elkashlan, Maged
    Yeoh, Phee Lep
    Poor, H. Vincent
    Lee, Moon Ho
    Spectrum Sharing Single-Carrier in the Presence of Multiple Licensed Receivers2013Ingår i: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 12, nr 10, s. 5223-5235Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, maximal-ratio combining (MRC) and selection combining (SC) are proposed in spectrum sharing single-carrier networks with multiple primary user receivers (PU-Rxs). Taking into account the peak interference power at the PU-Rx's and the maximum transmit power at the secondary user (SU), the impact of multiple PU-Rx's on the secondary network is characterized when the secondary user receiver (SURx) is equipped with multiple antennas. In doing so, exact and asymptotic expressions are derived for the cumulative distribution function, taking into account two realistic scenarios: 1) non-identical frequency selective fading between the secondary user transmitter (SU-Tx) and the PUs, and 2) frequency selective fading between the SU-Tx and the SU-Rx. Based on these, exact and asymptotic expressions for the outage probability and average bit error rate are derived. Furthermore, an exact closedform expression for the ergodic capacity is derived. It is shown that the asymptotic diversity gain depends only on the number of receive antennas and the number of multipath channels. It is further shown that the number of PU-Rx's and fading severities between the SU-Tx and the PU-Rx's have no impact on the asymptotic diversity gain.

  • 45.
    Kodide, Alekhya
    et al.
    Blekinge Tekniska Högskola, Fakulteten för teknikvetenskaper, Institutionen för tillämpad signalbehandling.
    Chu, Thi My Chinh
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kreativa teknologier.
    Zepernick, Hans-Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Outage probability of multiple relay networks over kappa-mu Shadowed fading2016Ingår i: 2016, 10th International Conference on Signal Processing and Communication Systems, ICSPCS 2016 - Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we study the outage probability of an opportunistic multiple relay communication system over κ-μ shadowed fading channels for both amplify-and-forward and decode-and-forward relaying protocols. We first provide an exact analysis of the impact of κ-μ shadowed fading on the outage probability of the system. To simplify the obtained analytical expression of the outage probability, we further approximate the κ-μ, shadowed fading channel by a Nakagami-m fading model. In order to illustrate the suitability of the approximation, numerical results are provided revealing that the exact outage probability using κ-μ, shadowed fading and the results obtained by approximating the fading by the Nakagami-m fading model match well as long as the parameters of the shadowed fading translate to integer values of the fading severity parameter m. Further, Monte-Carlo simulations have been conducted to validate the derived analytical expressions of the outage probability. Finally, the effect of network parameters such as the average transmit power at the source and the relay, the impact of the number of relays, the influence of the transmission distances and the fading parameters on the outage probability of the considered system is also illustrated through numerical examples. © 2016 IEEE.

  • 46.
    Kolomvakis, Nikolaos
    et al.
    Ericsson Research and Ericsson Ab, SWE.
    Eriksson, Thomas
    Chalmers University of Technology, SWE.
    Coldrey, Mikael
    Ericsson Research and Ericsson Ab, SWE.
    Viberg, Mats
    Blekinge Tekniska Högskola, Ledningen.
    Quantized Uplink Massive MIMO Systems with Linear Receivers2020Ingår i: IEEE International Conference on Communications, Institute of Electrical and Electronics Engineers Inc. , 2020, artikel-id 9149088Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper considers the uplink of a single-cell multi-user massive multiple-input multiple-output (MIMO) system. Each receiver antenna of the base station is assumed to be equipped with a pair of analog-to-digital converters (ADCs) to quantize the real and imaginary part of the received signal. We propose a novel Bussgang-based weighted zero-forcing (B-WZF) receiver, which distinguishes the clipping and granular distortion. Numerical results demonstrate that for sufficiently high SNR and users that do not experience deep large-scale fading, the B-WZF brings significant performance gain over existing linear receivers in the literature, when the training sequence length is higher than the number of users. © 2020 IEEE.

  • 47.
    Kuruganti, NSR Sankaran
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för kommunikationssystem.
    Distributed databases for Multi Mediation: Scalability, Availability & Performance2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Context: Multi Mediation is a process of collecting data from network(s) & network elements, pre-processing this data and distributing it to various systems like Big Data analysis, Billing Systems, Network Monitoring Systems, and Service Assurance etc. With the growing demand for networks and emergence of new services, data collected from networks is growing. There is need for efficiently organizing this data and this can be done using databases. Although RDBMS offers Scale-up solutions to handle voluminous data and concurrent requests, this approach is expensive. So, alternatives like distributed databases are an attractive solution. Suitable distributed database for Multi Mediation, needs to be investigated.

    Objectives: In this research we analyze two distributed databases in terms of performance, scalability and availability. The inter-relations between performance, scalability and availability of distributed databases are also analyzed. The distributed databases that are analyzed are MySQL Cluster 7.4.4 and Apache Cassandra 2.0.13. Performance, scalability and availability are quantified, measurements are made in the context of Multi Mediation system.

    Methods: The methods to carry out this research are both qualitative and quantitative. Qualitative study is made for the selection of databases for evaluation. A benchmarking harness application is designed to quantitatively evaluate the performance of distributed database in the context of Multi Mediation. Several experiments are designed and performed using the benchmarking harness on the database cluster.

    Results: Results collected include average response time & average throughput of the distributed databases in various scenarios. The average throughput & average INSERT response time results favor Apache Cassandra low availability configuration. MySQL Cluster average SELECT response time is better than Apache Cassandra for greater number of client threads, in high availability and low availability configurations.Conclusions: Although Apache Cassandra outperforms MySQL Cluster, the support for transaction and ACID compliance are not to be forgotten for the selection of database. Apart from the contextual benchmarks, organizational choices, development costs, resource utilizations etc. are more influential parameters for selection of database within an organization. There is still a need for further evaluation of distributed databases.

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  • 48.
    Kuzminykh, Ievgeniia
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Carlsson, Anders
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Franksson, Robin
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Liljegren, Alexander
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Measuring a LoRa Network: Performance, Possibilities and Limitations2018Ingår i: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) / [ed] Galinina O., Andreev S., Balandin S., Koucheryavy Y., Springer, 2018, Vol. 11118, s. 116-128Konferensbidrag (Refereegranskat)
    Abstract [en]

    Low power wide area (LPWA) technologies becomes popular for IoT use cases because LPWA is enable the broad range communications and allows to transmit small amounts of information in a long distance. Among LPWA technologies there are LTE-M, SigFox, LoRa, Symphony Link, Ingenu RPMA, Weightless, and NB-IoT. Currently all these technologies suffer from lack of documentation about deployment recommendation, have non-investigated limitations that can affect implementations and products using such technologies. This paper is focused on the testing of LPWAN LoRa technology to learn how a LoRa network gets affected by different environmental attributes such as distance, height and surrounding area by measuring the signal strength, signal to noise ratio and any resulting packet loss. The series of experiments for various use cases are conducted using a fully deployed LoRa network made up of a gateway and sensor available through the public network. The results will show the LoRa network limitation for such use cases as forest, city, open space. These results allow to give the recommendation for companies during early analysis and design stages of network life circle, and help to choose properly technology for deployment an IoT application.

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  • 49.
    Kuzminykh, Ievgeniia
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Carlsson, Anders
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datavetenskap.
    Yevdokymenko, Maryna
    Kharkiv National University of Radio Electronics, UKR.
    A performance evaluation of sensor nodes in the home automation system based on arduino2019Ingår i: 2019 IEEE International Scientific-Practical Conference: Problems of Infocommunications Science and Technology, PIC S and T 2019 - Proceedings, Institute of Electrical and Electronics Engineers Inc. , 2019, s. 511-516, artikel-id 9061442Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, a home automation system model was constructed with purpose to investigate of the correlation between the performance of wireless communication, power consumption of the constrained IoT devices and security. The series of experiments were conducted using sensor nodes connected to Arduino microcontroller and an RF 433 MHz wireless communication module. Measurements of the execution time and power consumption of the Arduino during data transfer with different security levels, as well as the analysis of the experimental results, were performed. The results show that the lifetime of the IoT device is determined by the communication speed, sleep mode management and depends on encryption. The obtained results can be used to minimize the power consumption of the device and improve communication efficiency. The results show that applied security reduces the productivity and lifetime of the sensor node not significantly. © 2019 IEEE.

  • 50.
    Kuzminykh, Ievgeniia
    et al.
    Kharkiv National University, UKR.
    Snihurov, Arkadii
    Kharkiv National University, UKR.
    Carlsson, Anders
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för datalogi och datorsystemteknik.
    Testing of communication range in ZigBee technology2017Ingår i: 14th International Conference The Experience of Designing and Application of CAD Systems in Microelectronics (CADSM), Institute of Electrical and Electronics Engineers (IEEE), 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Abstract:In the rapidly growing Internet of Things (loT) applications from personal electronics to industrial machines and sensors are getting wirelessly connected to the Internet. Many well-known communication technologies such as WiFi, ZigBee, Bluetooth and cellular are used for transfer data in IoT. The choice of corresponding technology or combination of technologies depends on application or other factors such as data requirements, communication range, security and power demands, battery life. In this paper we will focus on ZigBee wireless technology and testing ZigBee end devices in order to see how transmission range impacts on quality parameters.

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