This diploma thesis deals with the design of low-power IoT device communicating by using the NB-IoT standard. The theoretical part of the thesis is dedicated to the explanation of the principles and capabilities of communication in IoT networks Sigfox, LoRa and NB-IoT, and also its physical layer, network architecture, techonology principles and frequency bands used. The application part of the thesis is dedicated to design of the NB-IoT device from the system design through the selection of main components to the detailed physical design of the device. Two prototypes of the device with two different radio modules used are fabricated on which is performed measurement of the power profile of the device in various operation modes.

Dans le contexte de l'Internet des Objets (IoT), on estime à plus de 10% la proportion de connections réalisées via les réseaux longue portée bas débit, représentant ainsi plusieurs milliards d’objet connectés. Afin de satisfaire les exigences en termes de sensibilité et de réduction du débit, deux approches sont généralement envisagées : l’approche bande étroite, et l’approche faible efficacité spectrale. En comparant les performances des systèmes existants à la limite théorique issue de la théorie de l'information et démontrée par Shannon, on constate qu’un gain en performance est atteignable, tout en travaillant toujours à de faibles niveaux de sensibilité. La théorie de l'information permet d'affirmer qu'un compromis entre l'efficacité spectrale et l'efficacité énergétique doit toujours être fait. Ainsi, une haute efficacité énergétique s'obtiendra au détriment d'une efficacité spectrale faible. A l'inverse, un système fonctionnant à une haute efficacité spectrale devra utiliser plus d'énergie pour transmettre le même nombre de bits et atteindre le même taux d'erreur.Ce travail s’intéresse à l’approche faible efficacité spectrale. En partant des modulations orthogonales, qui permettent d’atteindre la limite théorique de Shannon à des efficacités spectrales très faibles, et des processus turbo, qui atteignent d’excellentes performances à des efficacités spectrales élevées, l’utilisation conjointe d’une modulation orthogonale et d'un code correcteur associés à un récepteur itératif dans une technique dénommée Turbo-FSK est étudiée. Les différents paramètres de la technique sont optimisés en utilisant un outil classique des processus itératifs, l’Extrinsic Information Transfer (EXIT) chart. Les performances mesurées démontrent que la technique permet bien d’atteindre de très faibles niveaux de sensibilité et répond aux critères des réseaux longue portée bas débit. Cependant, la technique ne dispose de point de fonctionnement qu’à de très faibles valeurs d’efficacité spectrale : pour certaines applications ou si la portée nécessaire est réduite, il peut être bénéfique pour le système d’augmenter son efficacité spectrale. Ceci est rendu possible grâce à l’introduction d’une composante linéaire dans l’alphabet de modulation et d’un mécanisme de poinçonnage spécifique à la technique dans une version flexible appelée Coplanar Turbo-FSK. L’étude de l’influence des paramètres et des performances sur un canal à bruit blanc additif gaussien permet en effet de conclure sur la flexibilité de l’efficacité spectrale du système, tout en fonctionnant proche de la limite théorique. Finalement, l’étude jusqu’ici théorique est étendue à un contexte plus pratique, où des canaux sélectifs en fréquences sont considérés. Une encapsulation du système utilisant une architecture OFDM est considérée, et différentes mesures caractéristiques des systèmes de télécommunication sont évaluées. Les résultats sont confrontés à la solution Narrow-Band IoT proposée par l’organisme 3GPP et démontrent ici encore le potentiel de la solution Turbo-FSK pour les réseaux longue portée bas débit. / More than 10% of the Internet-of-Things (IoT) connections are expected to be realized through Low Power Wide Area (LPWA) networks, representing several billions of connected devices. Several industrial solutions have been developed and a standardization process is ongoing. The low levels of sensitivity and low data rate required for the long range communication are achieved by the means of two strategies: a narrow-band strategy and a low spectral efficiency strategy. Considering the limits of the information theory, additional gains in the communication's energy efficiency can be achieved. Nonetheless, a trade-off between spectral efficiency and energy efficiency should always be made. Reliable transmission with high energy efficiency will necessarily result in poor spectral efficiency, and in comparison, a system with a higher spectral efficiency has to consume more energy to transmit the same amount of bits with the same arbitrary level of error.This work considers the low spectral efficiency strategy. The combination of orthogonal modulations and a powerful channel code is studied. The scheme, so-called Turbo-FSK, associates the low spectral efficiency of Frequency Shift Keying (FSK) with the energy efficiency gain of a turbo receiver. Low levels of spectral efficiency can be achieved while optimizing the use of the available resource. The parameters of the scheme are optimized using a classic tool for iterative receivers, the Extrinsic Information Transfer (EXIT) chart. Performance of Turbo-FSK compared to existing LPWA solutions demonstrates the potential of the proposed solution to achieve low levels of sensitivity and to outperform existing schemes. However, the restrictions on low levels of spectral efficiency reduces the number of possible applications for the scheme. By introducing a linear component in the alphabet and a puncturing procedure, flexibility in spectral efficiency is achieved. A large range of spectral efficiencies can be obtained while maintaining performance close to the channel capacity theoretical limit. Eventually, more practical scenarios are considered for evaluating the performance of the scheme. Frequency selective channels are considered and an encapsulation in a Fast Fourier Transform (FFT) based system is implemented. Various indicators are studied and the Turbo-FSK scheme is compared to well-known technologies, such as schemes using Orthogonal Frequency Division Multiplexing (OFDM) associated with a powerful Forward Error Correction (FEC) scheme, namely Turbo Code (TC).

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.

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.

Technology Narrowband IoT is a representative LPWA (Low Power Wide Area) tech-nology that due to its promising features aims for demands of the Internet of Thingsapplications for autonomous data sending from sensors in areas of poor mobile coverage.For such applications, it is beneficial to firstly map properties of communication technol-ogy in areas of intended use and evaluate whether or not is this technology applicable.This Master thesis deals with the design of the hand-held measuring device for evaluationof Narrowband IoT properties. The output of this thesis is firstly comparison of LPWAtechnologies secondly, design of the mentioned device and verification of its functional-ity. And in last part description of measurement of transmission delay for delay-tolerantapplications. Transmission delay is a critical parameter for delay-tolerant applications.Such an application can be, for example, smart electrometers for which there is definedmaximal allowed transmission delay of 10 seconds and therefore it is desirable to evalu-ate whether or not is the deployment of the communication technology Narrowband IoTsuitable in the intended area for delay-tolerant or even for delay-intolerant applications.