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  • 1.
    Antoja Lleonart, Guillem
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    New Generation 4-Channel GNSS Receiver: Design, Production, and Testing2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Due to the current research needs and the lack of commercial multi-channel, multi-constellation GNSS receivers, a two-board solution has been developed so it can be mated with and take advantage of the processing power of the FPGA board branded as MicroZed.

    In order to achieve the proposed goals, an initial phase for assessing and updating the older design, building, and testing of SiGe modules (including both the electronics and casings) has been carried out. The results included demonstrate performances at logging GPS-L1 data with similar C/N0 and AGC values as the previous versions of the modules and offering navigation solutions with accuracies of a few meters. Secondly, a first iteration and design proposal for the new generation receiver has been proposed for GPS and GLONASS L1 and L2, which has been manufactured and tested. Partial tests have been performed due to the flaws of the current revision of the MicroZed Board in regards to its communication peripherals, and the results have validated the receiver’s design provided certain modifications are considered for future iterations. Furthermore, voltage and frequency tests have provided results with an error of less than 7%, and signal tests have provided C/N0 values similar to those of the SiGe modules of around 47[dB-Hz] which will be a useful baseline for future iterations. Finally, a design proposal for an Interface Board used between the older NT1065_PMOD Board and other FPGA boards carrying the standardized FMC connectors has been added to the report and negotiations with manufacturers have been engaged.

  • 2.
    Bezerra, Nibia Souza
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Saguna, Saguna
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    de Sousa Jr., Vicente A.
    Federal University of Rio Grande do Norte.
    Propagation Model Evaluation for LoRaWAN: Planning Tool Versus Real Case Scenario2019Ingår i: 2019 IEEE 5th World Forum on Internet of Things (WF-IoT) / [ed] IEEE, https://ieeexplore.ieee.org/document/8767299, 2019, s. 1-6Konferensbidrag (Refereegranskat)
    Abstract [en]

    LoRa has emerged as a prominent technology for the Internet of Things (IoT), with LoRa Wide Area Network (LoRaWAN) emerging as a suitable connection solution for smartthings. The choice of the best location for the installation of gateways, as well as a robust network server configuration, are key to the deployment of a LoRaWAN. In this paper, we present an evaluation of Received Signal Strength Indication (RSSI) values collected from the real-life LoRaWAN deployed in Skellefteå, Sweden, when compared with the values calculatedby a Radio Frequency (RF) planning tool for the Irregular Terrain Model (ITM), Irregular Terrain with Obstructions Model (ITWOM) and Okumura-Hata propagation models. Five sensors are configured and deployed along a wooden bridge, with different Spreading Factors (SFs), such as SF 7, 10 and 12. Our results show that the RSSI values calculated using the RF planning tool for ITWOM are closest to the values obtained from the real-life LoRaWAN. Moreover, we also show evidence that the choice of a propagation model in an RF planning tool has to be made with care, mainly due to the terrain conditions of the area where the network and the sensors are deployed.

  • 3.
    Carlson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    van de Beek, Jaap
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Mohamad, Medhat
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Mbit/second Communication through a Rock Bolt Using Ultrasound2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    In most industrial processes transfer of data and software from or to sensors is an essential part of the monitoring and control systems. Many of the older, wired communication systems have been or are being replaced with wireless alternatives. A number of challenges are associated with this replacement: Radio receivers are subject to interference from other radio sources. Similarly, radio transmitters may cause undesired interference into other equipment and environments. Compared to wired solutions, security becomes an issue as radio communication links are more vulnerable to eavesdropping than wired schemes. Radio communication with sensors and sensor platforms embedded deep inside large metal structures or fluid tanks may be difficult or even impossible. The objective of this work is to develop and evaluate a high data-rate communications scheme based on ultrasound, which can be used to transmit wirelessly through solid structures. An example will be given using a one-meter segment of a rock bolt.

  • 4.
    Carlson, Johan
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    van de Beek, Jaap
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Mohamad, Medhat
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Mbit/second Communication through a Rock Bolt Using Ultrasound2017Ingår i: IEEE International Ultrasonics Symposium, IUS, Piscataway, NJ: IEEE Computer Society, 2017, artikel-id 8092474Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents a digital communication system based on Orthogonal Frequency Division Multiplexing (OFDM) and MHz-range ultrasound, for transmission of data through solid materials and liquids. The system is tested on experiments using a off-the-shelf ultrasound transducers with a center frequency of 3.5 MHz as transmitter and receiver, respectively. The propagation medium in the experiment was a 1 m long section of an epoxy coated steel rock bolt. The results show that data rates in excess of 1 Mbit/second is attainable, using readily available hardware and software.

  • 5.
    Halén, Axel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Cloud Monitoring and observation measurements in OpenStack environment2018Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 6.
    Jasim, Al-Hussein Hameed
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Blixt™: An Available Bandwidth Measurements’ Approach for High-Speed Mobile Networks2018Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Mobile networks are in the process of becoming the world’s leading medium for data traffic. This challenge has raised the bar for Quality of Services (QoS) provided by the mobile network operators. It requires methods and tools to verify the Service Level Agreement (SLA) and benchmark competitors by comparing metrics of QoS, e.g. the round-trip time and available bandwidth. For this purpose, Blixt™ has been developed, which is a property of InfoVista Sweden AB. Blixt™ is an Android application which measures the available bandwidth and the round-trip time for the latest generation of mobile networks. Blixt™ approach relies on a time-stamping protocol commonly known as Two-Way Active Measurement Protocol (TWAMP). This research work discusses how the packet probing parameters affect the accuracy of measurements and the level of intrusiveness. The performance of the technique was experimentally tested and compared to other tools and methods, namely, iPerf3, nPerf and FTP test.

  • 7.
    Krasheninnikov, Pavel V.
    et al.
    Siberian State University of Telecommunications and Information Sciences, Novosibirsk, Russia.
    Melent’ev, Oleg G.
    Siberian State University of Telecommunications and Information Sciences, Novosibirsk, Russia.
    Kleyko, Denis
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Shapin, Alexey
    Ericsson Research, Luleå, Sweden.
    Parameter Estimation for the Resulting Logical Channel Formed by Minimizing Channel Switching2019Ingår i: Automation and remote control, ISSN 0005-1179, E-ISSN 1608-3032, Vol. 80, nr 2, s. 278-285Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We propose a method for calculating the parameters of the resulting discrete channel for secondary users in cognitive radio systems formed by the algorithm for minimizing channel switchings. The availability of channel slots is defined by a simple Markov chain. We obtain mathematical expressions for determining the transition probabilities of a graph reduced to two states for any number of primary channels.

  • 8.
    Lyamin, Nikita
    et al.
    Halmstad University, Sweden.
    Kleyko, Denis
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Delooz, Quentin
    University of Liège, Belgium.
    Vinel, Alexey
    Halmstad University, Sweden.
    AI-Based Malicious Network Traffic Detection in VANETs2018Ingår i: IEEE Network, ISSN 0890-8044, E-ISSN 1558-156X, Vol. 32, nr 6, s. 15-21Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Inherent unreliability of wireless communications may have crucial consequences when safety-critical C-ITS applications enabled by VANETs are concerned. Although natural sources of packet losses in VANETs such as network traffic congestion are handled by decentralized congestion control (DCC), losses caused by malicious interference need to be controlled too. For example, jamming DoS attacks on CAMs may endanger vehicular safety, and first and foremost are to be detected in real time. Our first goal is to discuss key literature on jamming modeling in VANETs and revisit some existing detection methods. Our second goal is to present and evaluate our own recent results on how to address the real-time jamming detection problem in V2X safety-critical scenarios with the use of AI. We conclude that our hybrid jamming detector, which combines statistical network traffic analysis with data mining methods, allows the achievement of acceptable performance even when random jitter accompanies the generation of CAMs, which complicates the analysis of the reasons for their losses in VANETs. The use case of the study is a challenging platooning C-ITS application, where V2X-enabled vehicles move together at highway speeds with short inter-vehicle gaps.

  • 9.
    Marques Lima, Francisco Rafael
    et al.
    Luleå tekniska universitet, Extern.
    Maciel, Tarcisio
    Luleå tekniska universitet, Extern.
    da CRUZ FREITAS JUNIOR, Walter
    Luleå tekniska universitet, Extern.
    Porto Cavalcanti, Francisco Rodrigo
    Souza Bezerra, Nibia
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    B. Rodrigues, Emanuel
    Method and apparatus for resource allocation satisfying multiple performance constraints2013Patent (Övrig (populärvetenskap, debatt, mm))
  • 10.
    Nilsson, Daniel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Rymdteknik.
    Evaluation of Secure Long Distance Communication in Non-Urban Environments2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 11.
    Palm, Jonathan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Optimization of 5G New Radio for Fixed Wireless Access2019Självständigt arbete på avancerad nivå (yrkesexamen), 300 hpStudentuppsats (Examensarbete)
    Abstract [en]

    With the advent of new 5G networks, the interest in connecting house-hold to the Internet via mobile networks has increased. One such way toconnect users is using completely stationary antennas. This use-case iscalled Fixed Wireless Access (FWA) and is seen as promising, cost-efficient means of expanding internet connectivity. Stationary users connected at high frequencies, such as 28 GHz, leads to a special use-case and environment for 5G New Radio (NR). This thesis investigates the characteristics of these FWA deployments and the control signaling on the physical layer of NR. The overhead and feasibility of eachsignal is considered. A FWA deployment in the 28 GHz band with 64 users is simulated with different line-of-sight settings and receiver placements. It is concluded that direct line-of-sight to the base station is vital for high user and cell throughput and that there are significant drawbacks of placing the receiver indoors. New algorithms for Channel State Information Reference Signal (CSI-RS) transmission for both beam management and link adaptation are proposed and evaluated. The beam management algorithms do not displayany significant performance gains over the default sweeping algorithm. Closer investigation of simulation results shows that several beams can have almost equal signal strength with the chosen antenna set up, minimizing potential gains of quickly adapting to environmental changes. Results show there are clear benefits of using an aperiodic and adaptive transmission scheme for CSI-RS transmissions over a fixed-rate transmission scheme, yielding a 7% increase in user goodput at similar levels of overhead.

  • 12.
    Perdomo, José
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    UE Performance in a 5G Multi-connectivity UDN City Scenario2019Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Multi-connectivity and network densification are two solutions intended to enhance user throughput and reliability. These solutions are critical since 5G NR uses a wide range of frequency bands, which exhibit different varying radio coverage characteristics. This work studies the user equipment (UE) performance using multi-connectivity within an ultra-dense network (UDN) deployed in an urban city environment. By being connected to more than one access node simultaneously, the UE should benefit from increased reliability and data rates at the expense of a potentially increased power consumption. In this letter, we have constructed an urban city environment and a context-aware UE power consumption model. The performance of the UE is assessed with an uplink power control scheme for multi-connectivity and a novel multi-connectivity scheme is proposed. Our simulation results show that dual-connectivity increases performance by up to 44% and 27% in average downlink and uplink throughput, respectively. Similarly, tri-connectivity does the same by up to 45% and 25%. At mid load (forty-five users), the average increase in UE power consumption compared to single-connectivity is 25% and 60% for dual-connectivity and tri-connectivity, respectively. Dual-connectivity increases global UE energy efficiency by up to 30%. Within an urban environment, dual-connectivity decreases the RLF rate by 20% compared to single-connectivity for high speed users.

  • 13.
    Pinoé Chacón, Luis
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    IEEE 802.11nImplementering och Analys: Accesspunkter2014Självständigt arbete på grundnivå (högskoleexamen), 5 poäng / 7,5 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Sammanfattning

    Detta examensarbete har genomförts på företaget Axe'L Dataservice. Mitt uppdrag var att implementera ett trådlöst nätverk åt företaget GUNSHILL AB.

    GUNSHILL AB bedriver mjölk- och köttproduktion och använder ett robot-mjölksystem som heter Lely. Detta system styrs via applikationer som installeras i Android- eller iPhone-enheter.

    Det trådlösa nätverket hade som mål att täcka mjölkproduktions-anläggningen, på ungefär trehundrafemtio kvadratmeter totalt.

    I samband med analysen av det trådlösa nätverket, installerade vi ett övervakningssystem. Detta används framförallt som ett testverktyg för att övervaka accesspunkterna under implementeringen samt ge en inblick till företaget GUNSHILL AB om hur användbart och effektivt övervaknings-systemet är.

    Denna rapport redovisar processen för de genomförda implementeringarna samt beskriver en analys av IEEE 802.11n-teknologin i förhållande till Ubiquiti-utrustningen som används i detta projekt.

    Resultaten av detta examensarbete uppfyller de krav som företaget GUNSHILL AB hade ställt upp. Det implementerade trådlösa nätverket täcker trehundrafemtio kvadratmeter och levererar en Internet-hastighet upp till 6.4 Mbit/s, vilket motsvarar ungefär 90.6 % av den ursprungliga Internet-hastigheten som är 7 Mbit/s.

  • 14.
    Poirot, Valentin
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Energy-Efficient Multi-Connectivity for Ultra-Dense Networks2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In 5G systems, two radio air interfaces, evolved LTE and New Radio (NR), will coexist. By using millimeter waves, NR will provide high throughputs, but the higher frequencies will also lead to increased losses and a worse coverage. Multi-connectivity is therefore envisioned as a way to tackle these effects by connecting to multiple base stations simultaneously, allowing users to benefit from both air interfaces’ advantages. In this thesis, we investigate how multi-connectivity can be used efficiently in ultra-dense networks, a new paradigm in which the number of access nodes exceeds the number of users within the network. A framework for secondary cell association is presented and an energy efficiency’s condition is proposed. Upper and lower bounds of the network’s energy efficiency are analytically expressed. Algorithms for secondary cell selection are designed and evaluated through simulations. Multi-connectivity showed an improvement of up to 50% in reliability and and an increase of up to 20% in energy efficiency.

  • 15.
    Van-Eckmann, Nik
    Luleå tekniska universitet, Institutionen för konst, kommunikation och lärande, Medier ljudteknik och upplevelseproduktion och teater.
    Wildlife Sound Recording: Dealing With The Distance And On-Axis Issues2017Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    In natural history filmmaking recording fauna vocalisation often produces difficult challenges especially when recording sound from a distance. The camera in many cases is able to solve these problems due to lens changes, but the microphone cannot do this, which creates major problems when combining sound and picture. This thesis using a multi disciplinary approach, looks at these problems in particular the 'Distance' and 'On-Axis' issues and attempts to solve them using both a theoretical and practical approach. The thesis consists of two parts, part one the theoretical section discusses the idiosyncrasies of natural history sound recording giving examples where the problems of actual situations have been resolved. Part two is an applied method or practical experimentation using technology designed to test certain theories in effectively dealing with the 'Distance' and 'On-Axis' issues. The practical experimentation takes place at various locations using avian subjects to demonstrate the problems and solutions when recording wildlife vocalisation. As a result of the tests, a remote-controlled microphone operating system was developed and tested in the field to ascertain its capabilities. Although still a prototype it has the potential through further development, to be a useful technological instrument for recording wildlife sound.

  • 16.
    Zhohov, Roman
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Evaluating quality of experience and real-time performance of industrial internet of things2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The Industrial Internet of Things (IIoT) is one of the key technologies of Industry 4.0 thatwill be an integral part of future smart and sustainable production. The current constitutedmodels for estimating Quality of Experience (QoE) are mainly targeting the multimediasystems. Present models for evaluating QoE, specifically leveraged by the expensivesubjective tests, are not applicable for IIoT applications. This work triggers the discussionon defining the QoE domain for IIoT services and applications. Industry-specific KPIs areproposed to assure QoE by linking business and technology domains. Tele-remote miningmachines are considered as a case study for developing the QoE model by taking intoaccount key challenges in QoE domain. As a result, QoE layered model is proposed, whichas an outcome predicts the QoE of IIoT services and applications in a form of pre-definedIndustrial KPIs. Moreover, software tool and analytical model is proposed to be used as anevaluation method for certain traffic types in the developed model.

1 - 16 av 16
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