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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Study of Low-Power Wide-Area Networks and an In-Depth Study of the LoRaWAN Standard

PETTER, LAGUSSON, JOHANNA, NORDLÖF January 2017 (has links)
Low Power Wide Area Networks (LPWAN) are able to combine long range communication with a low energy consumption sacrificing performance in terms of bit rate and message frequency. This thesis presents a general evaluation of the LPWAN characteristics and a description of the LPWAN protocols LoRaWAN, SigFox and NB-IoT. It also covers a method to evaluate if a LPWAN technology would be a suitable choice of communication technology for a certain use case. Lastly, it covers the implementation of LoRaWAN on a connected electromechanical lock and investigates in the real life performance of the lock by using eight nodes in two case studies involving four locations each. The lock was evaluated from how often it was able to send a heartbeat (a status message), how reliable the communication was, what latency a user could expect and how much energy a data transmission required. Two of the eight nodes were placed in a deep indoor environment. One of them, located 0.794 km from a gateway was able transmit every 150th second. The other one located 1.85 km from a gateway was not able to successfully deliver any packets at all. Five nodes were able to transmit most heartbeats within 10 seconds. The Packet Delivery Ratio (PDR) was below 90% for all locations except for one. In this location, the node was placed close to a large window and managed to communicate with a gateway 3.22 km away with a PDR of 97% and almost exclusively with less than 10 seconds between transmission. The results in this thesis show the potential in LoRaWAN but highlights how dependent the performance will be of the placement of the lock. / Genom att kombinera låg dataöverföringshastighet och låg meddelandefrekvens kan LPWAN uppnå en kommunikation med lång räckvidd och låg energiförbrukning. Denna uppsats går igenom vad som karaktäriserar LPWAN i stort samt presenterar LPWAN-protokollen LoRaWAN, SigFox och NB-IoT. Den visar även en metod vilken kan användas för att utvärdera hur väl ett use case lämpar sig för LPWAN-tekniken. Slutligen görs en implementering av LoRaWAN i ett uppkopplat lås från ASSA ABLOY för att undersöka vilken prestanda som är möjlig att uppnå för åtta olika noder i två olika fallstudier. Låset utvärderades utfirån hur ofta det kunde skicka statusmeddelanden, hur tillförlitlig kommunikationen var samt hur mycket energi som förbrukades. Två av åtta noder placera-des långt in i sina respektive byggnader, den ena kunde endast skicka statusuppdateringar i intervaller om 150 sekunder och den andra lyckades inte leverera några datapaket alls. Fem noder lyckades skicka de flesta statusuppdateringerna i intervall under tio sekunder. Resultatet visade på en packet delivery ratio under 90% i samtliga fall förutom ett. Där placerades noden nära ett stort fönster och lyckades kommunicera med en gateway 3.22 km bort med en PDR på 97% och mindre än 10 sekunder mellan sändningarna. Detta resultat visar potentialen för LoRaWAN men belyser även hur beroende prestandan kommer att vara av hur låset placeras.
2

Energy Consumption of Low Power Wide Area Network Node Devices in the Industrial, Scientific and Medical Band

Eriksen, Rúni January 2019 (has links)
Low-Power Wide-Area Networks, LPWANs, achieve long communication ranges with a low energy consumption by communicating at low bit rates. Most LPWAN devices are battery powered and are required to operate for an extended period of time, which stresses the requirements for energy efficiency. This thesis investigates the energy consumption of LPWAN devices operating in the Industrial, Scientific and Medical, ISM, band and how use cases affect the consumption. Specifically, LoRa/LoRaWAN and Sigfox are examined. Their key characteristics are described and energy consumption is modelled. The models are verified by comparing the model outputs with measured power consumption of LoRa and Sigfox devices. Through the models, design parameters are investigated with regards to consumption, and product lifetime are estimated. The influence of use cases on energy consumption is explored by measuring the Package Delivery Ratio, PDR, at different ranges using various bit transmission rates.The results showed that the bitrate, data redundancy and protocol overhead were among parameters which could be used to optimise energy efficiency. It was also shown, that the device lifetimes could be significantly increased by increasing the transmission interval and removing message acknowledgements. Realistically, LoRa devices can have a lifetime of more than 10 years and Sigfox 3 years, using a 2800 mWh battery. The use case tests showed that a 100 % PDR should not be expected at any bitrate, but lower bitrates and messaging redundancy increase the likelihood of a successful package delivery. Hence, there is a tradeoff between low energy consumption and range/reliability. Additionally, it was found that a low node to gateway distance and a high gateway density increase the probability of a successful transaction. Thus, the power consumption is tightly coupled to the network configuration. / Low-Power Wide-Area Networks, LPWANs, uppnår långa kommunikationsräckvidder med låg energiförbrukning genom att kommunicera med låga bithastigheter. De flesta enheter är batteridrivna och måste operera över längre tid, vilket ökar kraven för energieffektivitet. Denna avhandling undersöker energiförbrukningen för LPWAN enheter i det industriella, vetenskapliga och medicinska ISM bandet och hur olika användningsfall påverkar förbrukningen. Specifikt undersöks LoRa/LoRaWAN och Sigfox. Deras viktigaste egenskaper beskrivs och deras energiförbrukning modelleras. Modellerna verifieras genom att jämföra resultaten från modellerna med uppmätt effektförbrukning av LoRa och Sigfox-enheter. Genom modellerna undersöks även designparametrar med avseende på strömkonsumtion och produktens livslängd uppskattas. Påverkan användningsfall har på energiförbrukning undersöks genom att mäta Package Delivery Ratio, PDR, vid olika avstånd och bitöverföringshastigheter.Resultaten visade att bitraten, dataredundansen och protokollstorleken var bland parametrar som kunde användas för att optimera energieffektiviteten. Det visades också att enhetens livslängd kunde ökas signifikant genom att öka överföringsintervallet och ta bort meddelandebekräftelser. Realistiskt kan LoRaenheter ha en livslängd på mer än 10 år och Sigfox 3 år, med ett batteri på 2800 mWh. Resultatet av olika test visade att en 100 % PDR inte bör förväntas vid någon bitrate, men lägre bitrater och redundans för meddelanden ökar sannolikheten för en paketleverans. Det finns därför en avvägning mellan låg energiförbrukning och räckvidd och sannolikheten för en lyckad packetleverans. Dessutom konstaterades att en låg nod till gateway-avstånd och en hög gateway-densitet ökar sannolikheten för att transaktioner lyckas. Således är energiförbrukningen tätt kopplad till nätverkskonfigurationen.
3

Comparison of Performance and Power Consumption Between GPS and Sigfox Positioning Using Pycom Modules

Zhou, Xujia, Flora, Eduardo January 2018 (has links)
Sigfox is one of the newly-emerging LPWAN (Low Power Wide Area Network) technologies aiming to provide power-efficient solutions to the world of IoT. This study presents a comparison between Sigfox Geolocation and GPS (Global Positioning System) in terms of power consumption and performance which includes three metrics: accuracy and precision, response rate and response time. This study includes for the first part a series of lab tests where Sigfox Geolocation and GPS were studied in a single Sleep, Wake up, Idle, Tx/Rx cycle. For the second part, field tests with different geographical parameters (altitude, population, mobility) were conducted. Results of lab tests show that power consumption difference between Sigfox and GPS is a linear function of Idle time. In field tests, GPS presents a far superior performance than Sigfox in all metrics and marginally better power efficiency for relatively short Idle interval. For both GPS and Sigfox, a correlation between power efficiency and performance was observed. Results show that GPS operates best in rural environments while Sigfox stands out in urban ones. Payload size was observed to affect Sigfox in both power consumption and performance while different transmission rates only affect power consumption but do not seem to impact the other metrics. A solution based on the outcome of this study is suggested for a freight-monitoring system where geolocation is handled by GPS and the coordinates transmitted via Sigfox. As an emerging technology under constant development, Sigfox Geolocation is expected to have improved performance in the near future.
4

Posouzení informačního systému firmy a návrh změn / Information System Assessment and Proposal for ICT Modification

Červený, Radek January 2017 (has links)
This diploma thesis analyzes the information system of FCC Environment CEE and is focused on a detection of risks and other imperfections of the system. The result of the thesis should be a proposal for a change which may lead to an improvement of the entire system and eventually to elimination of the discovered risks.
5

Implementace a vyhodnocení komunikační technologie LoRaWAN v simulačním prostředí NS-3 / Implementation of the LoRaWAN Communication Technology Using the Network Simulator 3

Mašek, Petr January 2021 (has links)
The diploma thesis focuses on the description of LPWAN (Low Power Wide Area Network) technologies for use in IoT (Internet of Things) communication scenarios. The theoretical part compares communication technologies operating in the license-exempt frequency band, i.e. Sigfox and LoRaWAN (Long Range Wide Area Network). Furthermore, technologies using the licensed frequency spectrum are discussed, specifically, attention is focused on NB-IoT (Narrow Band IoT). Emphasis is placed on LoRaWAN technology and the properties of the unlicensed frequency band below the 1 GHz, which is utilized by this technology. The practical part of the thesis consists of the evaluation of simulation scenarios using an integrated module in the simulation environment NS-3 (Network Simulator 3). Attention is focused mainly on the analysis of data transmission success using selected communication parameters of LoRaWAN technology. The obtained simulation outputs with a focus on mMTC (massive Machine-Type Communication) communication scenarios confirm the relationship between the number of end devices and gateways, communication distance and transmission reliability, or the limit value for the duty cycle.
6

Návrh a realizace wattmetru s komunikací v síti IoT / Design and realization of the power meter with IoT connectivity

Zagrapan, Ivan January 2017 (has links)
This thesis deals with designing and creating working prototype of IoT Wattmeter with option to switching relay. This device can be control remotely with option to read measured values. To reach my goals, I am using open-source designing board, different sensors and modules. I tis possible to communicate with device through Wi-Fi module ESP 8266 and to test LPWAN network I am using SIGFOX, module. To measure current, it´s used simple Hall-effect sensor and all available information’s are displayed on OLED display. To switch the circuit off or on solid state relay was used. In theoretical part of the work, I am trying to explain working principles of every module and source code, which I am using to control these modules. In practical part I created scheme, using CADSoft EAGLE and created functional wattmeter. Whole work is programmed in C++ language using Arduino IDE.
7

Chytrý zámek využívající sítě IoT / Smart digital door lock system using IoT networks

Vitula, Marek January 2020 (has links)
This master thesis describes the design of a battery-powered smart lock using IoT networks and NFC technology for user authentication. The first part of the thesis describes the individual components to be used for the device design and also deals with the design of matching circuits and the antenna for the NFC. The following part of the thesis describes the design of the hardware, particularly the design of the printed circuit board. The third part describes the firmware and the final part of the thesis is dedicated to the security analysis.
8

Unlicensed and licensed low-power wide area networks : Exploring the candidates for massive IoT

Sjöström, Daniel January 2017 (has links)
In the Internet of things (IoT), many applications will require low-power and low-cost to achieve long lifetime and scale (respectively). These types of applications are referred to as massive IoT, as opposed to critical IoT, which emphasizes ultra-high reliability and availability and low latency. One type of network catering to massive IoT applications are Low-Power Wide Area Networks (LPWANs), and presently, many LPWAN standards are trying to assert their role in the IoT ecosystem. This thesis explores LPWANs from both technical and non-technical perspectives to ascertain their use-case versatility and influence on the future telecommunications’ landscape. With respect to spectrum, the studied LPWANs may be categorized as unlicensed LPWAN or licensed LPWAN. The prior category typically refers to proprietary solutions and in this thesis are represented by SigFox and LoRaWAN. The latter group includes EC-GSM-IoT, eMTC, and NB-IoT and can be considered synonymous with cellular LPWAN because they are designed to be integrated into existing cellular infrastructures. The results indicate that all of the different types of explored LPWANs support applications without strict downlink, payload size, and latency requirements. For use cases without these specific demands (typically sensors, meters, tracking, etc.), it is not a question of whether or not a network fulfills the requirements, but rather how flexible the requirements are. As a result the choice of network will be determined by non-technical aspects and a cost versus functionality trade-off where unlicensed LPWAN is typically cheaper. Hence, both categories of LPWANs offer a unique value proposition; therefore, they can be considered complementary. This notion is reinforced when looking at non-technical aspects such as ecosystem, regulation, network ownership and control, and network coordination, which differ quite significantly. Furthermore, unlicensed LPWANs are likely to be the vanguard of a new type of competitor offering the core service of connectivity. / Inom Internet of Things (IoT) kommer många applikationer att kräva låg effekt och låg kostnad för att uppnå en lång livstid och skala. Dessa typer av applikationer refereras till som massiv IoT, vilket står i motsats till kritisk IoT som kräver ultrahög tillförlitlighet och tillgänglighet och låg fördröjning. En typ av nätverk som ämnar tillgodose kraven av massiv IoT är Low-Power Wide Area Networks (LPWANs), och idag försöker många av dessa hävda sig inom IoT ekosystemet. Detta examensarbete undersöker LPWANs from ett teknisk och icke-tekniskt perspektiv för att utröna deras mångsidighet och påverkan på det framtida telekomlandskapet. Med avseende på spektrum kan de i detta examensarbete undersökta nätverken kategoriseras som olicensierat LPWAN eller licensierat LPWAN. Den tidigare hänvisar typiskt till proprietära lösningar och representeras i detta arbete av SigFox och LoRaWAN. Den senare kategorin består av EC-GSM-IoT, eMTC, och NB-IoT och kan betraktas som synonymt med mobil LPWAN eftersom de designade för att bli integrerade i existerande mobila nätverk. Resultaten indikerar att alla nätverk stödjer applikationer utan strikta krav när det gäller nedlänkens funktionalitet, mängden data per meddelande, och fördröjning. För applikationer utan dessa specifika krav (typiskt sensorer, mätare, spårning, etc.) är det inte en fråga om huruvida ett nätverk uppfyller kraven eller ej, utan snarare hur flexibla kraven är. Därför kommer valet av nätverk att bestämmas av icke-tekniska aspekter och en avvägning mellan kostnad och funktionalitet vari olicensierat LPWAN är vanligtvis billigare. Därmed erbjuder båda kategorier av nätverk en unik värde proposition och kan därför betraktas som komplementerande. Denna föreställning är förstärkt av att nätverken skiljer sig signifikant när det gäller deras icke-tekniska aspekter såsom ekosystem, reglering, ägandeskap och kontroll, och nätverks koordinering. Dessutom är olicensierade LPWANs troligen är förtruppen av en ny typ av konkurrent som erbjuder den grundläggande servicen av konnektivitet.
9

Implementace a vyhodnocení komunikační technologie LTE Cat-M1 v simulačním prostředí Network Simulator 3 / Implementation of Communication Technology LTE Cat-M1 Utilizing the Network Simulator 3

Drápela, Roman January 2019 (has links)
Diploma thesis deals with the implementation of LTE Cat-M1 technology in simulator NS--3 (Network Simulator 3). The theoretical part of the thesis summarizes key terms concerning IoT (Internet of Things), M2M (Machine-to-Machine) communication, LTE (Long Term Evolution) and LPWA (Low-Power Wide Area) networks. The practical part summarizes the possibilities of currently available modules for cellular technologies for NS-3, ie. the LENA module and the subsequent extension of LENA+ and ELENA. Simulation scenarios offer a comparison of LTE/LTE-A and LTE Cat-M1 (also known as eMTC - enhanced Machine Type Communication) technologies for M2M communication. The results of the simulations are well-arranged in the form of graphs and discussed at the end of the thesis.
10

Implementace a vyhodnocení komunikační technologie LTE Cat-M1 v simulačním prostředí NS-3 / Implementation of the LTE Cat-M1 Communication Technology Using the Network Simulator 3

Maslák, Roman January 2021 (has links)
The Diploma work deals with the implementation of LTE Cat-M technology in the simulation tool Network Simulator 3 (NS-3). The work describe LPWA technologies and their use cases. In first are described the main parts of the Internet of Things (IoT) and Machine-to-Machine (M2M) communication. Subsequently are described and defined the most used technologies in LPWA networks. Technologies which are used in the LPWA networks are Sigfox, LoRaWAN, Narrowband IoT (NB-IoT) and Long Term Evolution for Machines (LTE Cat-M), where LTE Cat-M technology is described in more details. Simulations are simulated in simulation tool NS-3 and use LENA module. In NS 3 tool are simulated Simulations, which give us informations of Network state according to different Network set up. At the end are done changes of Radio Resource Control (RRC) states in NS-3 tool. These changes are required for correct implementation LTE Cat-M technology in NS-3 tool. Then we are able to simulate simulations, which meet to definition of LTE Cat-M technology.

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