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Özenir, Onur. "Redundancy techniques for 5G Ultra Reliable Low Latency Communications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25082/.
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The 5G Core Network architecture is modeled to include instruments that can establish networks built on the same physical infrastructure but serve different service categories for communication types with varying characteristics. Relying on virtualization and cloud technologies, these instruments make the 5G system different from previous mobile communication systems, change the user profile, and allow new business models to be included in the system.
The subject of this thesis includes the study of Ultra-reliable low latency communication, which is one of the fundamental service categories defined for the 5G system, and the analysis of the techniques presented in 3GPP’s Release 16, which enhance the service parameters by modifying the core network. In the theoretical part, the 5G system and URLLC are introduced with a particular focus on the user plane on the core network. In the implementation part, redundant transmission support on the N3 interface, one of the techniques presented in the technical specification, is modeled using open source software tools (Open5GS and UERANSIM) and network virtualization instruments. As a result of the tests and measurements performed on the model, it was observed that the implemented technique enhanced the system's reliability.
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Faxén, Linnea. "A Study on Segmentation for Ultra-Reliable Low-Latency Communications." Thesis, Linköpings universitet, Kommunikationssystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138568.
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To enable wireless control of factories, such that sensor measurements can be sent wirelessly to an actuator, the probability to receive data correctly must be very high and the time it takes to the deliver the data from the sensor to the actuator must be very low. Earlier, these requirements have only been met by cables, but in the fifth generation mobile network this is one of the imagined use cases and work is undergoing to create a system capable of wireless control of factories. One of the problems in this scenario is when all data in a packet cannot be sent in one transmission while ensuring the very high probability of reception of the transmission. This thesis studies this problem in detail by proposing methods to cope with the problem and evaluating these methods in a simulator. The thesis shows that splitting the data into multiple segments and transmitting each at an even higher probability of reception is a good candidate, especially when there is time for a retransmission. When there is only one transmission available, a better candidate is to send the same packet twice. Even if the first packet cannot achieve the very high probability of reception, the combination of the first and second packet might be able to.För att möjliggöra trådlös kontroll av fabriker, till exempel trådlös sändning av data uppmätt av en sensor till ett ställdon som agerar på den emottagna signalen, så måste sannolikheten att ta emot datan korrekt vara väldigt hög och tiden det tar att leverera data från sensorn till ställdonet vara mycket kort. Tidigare har endast kablar klarat av dessa krav men i den femte generationens mobila nätverk är trådlös kontroll av fabriker ett av användningsområdena och arbete pågår för att skapa ett system som klarar av det. Ett av problemen i detta användningsområde är när all data i ett paket inte kan skickas i en sändning och klara av den väldigt höga sannolikheten för mottagning. Denna uppsats studerar detta problem i detalj och föreslår metoder för att hantera problemet samt utvärderar dessa metoder i en simulator. Uppsatsen visar att delning av ett paket i flera segment och sändning av varje segment med en ännu högre sannolikhet för mottagning är en bra kandidat, speciellt när det finns tid för en omsändning. När det endast finns tid för en sändning verkar det bättre att skicka samma paket två gånger. Även om det första paketet inte kan uppnå den höga sannolikheten för mottagning så kan kanske kombinationen av det första och andra paketet göra det.
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Kharel, B. (Binod). "Ultra reliable low latency communication in MTC network." Master's thesis, University of Oulu, 2018. http://jultika.oulu.fi/Record/nbnfioulu-201809212822.
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Abstract. Internet of things is in progress to build the smart society, and wireless networks are critical enablers for many of its use cases. In this thesis, we present some of the vital concept of diversity and multi-connectivity to achieve ultra-reliability and low latency for machine type wireless communication networks. Diversity is one of the critical factors to deal with fading channel impairments, which in term is a crucial factor to achieve targeted outage probabilities and try to reach out such requirement of five 9’s as defined by some standardization bodies. We evaluate an interference-limited network composed of multiple remote radio heads connected to the user equipment. Some of those links are allowed to cooperate, thus reducing interference, or to perform more elaborated strategies such as selection combining or maximal ratio combining. Therefore, we derive their respective closed-form analytical solutions for respective outage probabilities. We provide extensive numerical analysis and discuss the gains of cooperation and multi-connectivity enabled to be a centralized radio access network.
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Liu, Yuhong. "Quality of service improvement in interference-limited 5G networks." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29742.
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Fifth Generation (5G) networks are expected to support emerging applications with diverse quality of service (QoS) requirements, such as reliability, latency, and age-of-information. In conventional wireless networks, orthogonal resources are allocated to different transmitters to guarantee QoS performance. As the density of networks or devices increases, we need to increase the frequency reuse factor. Thus, interference becomes one of the bottlenecks for ensuring the QoS requirements of a large number of devices with limited time-frequency resources. This thesis presents novel methods for improving QoS performance in interference-limited networks. Specifically, we consider three typical scenarios: Ultra-reliable and Low latency communications (URLLC), time-critical applications, and multi-tenant communications.
In 5G networks, URLLC is one of the most challenging services with high reliability and low latency requirements. We define a new QoS metric, QoS violation probability, to measure the percentage of users without QoS guarantee. We propose a random packet repetition scheme that randomizes the interference power. The randomization is used to obtain diversity within the channel coherence time. The variation of interference can be exploited to reduce the QoS violation probability in interference-limited networks. Then, we optimize the number of reserved slots and the number of repetitions for each packet to minimize the QoS violation probability. We build a cascaded Random Edge Graph Neural Network (REGNN) to represent the repetition scheme and develop a model-free unsupervised learning method to train it. We analyze the QoS violation probability using stochastic geometry in a symmetric scenario and apply a model-based Exhaustive Search (ES) method to find the optimal solution. Simulation results show that in the symmetric scenario, the QoS violation probabilities achieved by the model-free learning method and the model-based ES method are nearly the same. In more general scenarios, the cascaded REGNN generalizes very well to wireless networks with different scales, network topologies, cell densities, and frequency reuse factors. It outperforms the model-based ES method in the presence of model mismatch.
For time-critical applications, we investigate the timely updates of short packets in interference-limited networks. Specifically, we minimize a performance metric, Age-of-Information (AoI), by optimizing the power control policy that is scalable to the number of wireless links. To find the optimal policy, we develop a deep reinforcement learning algorithm, graph-based deterministic policy gradient (GDPG). The actor and critic of the GDPG are represented by two types of graph neural networks (GNNs). We design two structures to implement the GDPG in a centralized and distributed manner. Simulation results show that when the number of wireless links in the testing stage is different from that in the training stage, the average AoI achieved by the GDPG is around $25\%$ lower than the WMMSE (weighted minimize mean square error) algorithm in a hexagonal cellular network and $50\%$ lower in a random network. The proposed methods are scalable to the number of wireless links in the network. With fine-tuning, our proposed two GDPG structures can be generalized well to networks with different densities and topologies.
Finally, we consider a multi-tenant network scenario, where multiple vertical industries or operators (acting as tenants) run their network on a single base station (BS). A new duality concept is developed to allocate precoding weights and transmit power at the BS so that the minimum isolation level from interference between tenants is maximized. A real-time multi-antenna multi-tenant BS (MBS) prototype is built by using commercial-off-the-shelf (COTS) software-defined-radio (SDR) boards. The over-the-air experiments show MBS provides a higher minimum isolation level and network capacity than other known algorithms.
The research on improving the QoS for different applications in 5G and beyond is developing rapidly. Possible future directions include 1) developing a more flexible transmission scheme that repeats the packet transmission in different resource blocks, 2) optimizing the peak AoI with a constraint on the tail probability, and 3) proposing a general solution for improving the QoS or other queue state information metrics in 5G interference-limited networks.
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Paquot, Yvan. "Novel linear and nonlinear optical signal processing for ultra-high bandwidth communications." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12408.
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The thesis is articulated around the theme of ultra-wide bandwidth single channel signals. It focuses on the two main topics of transmission and processing of information by techniques compatible with high baudrates. The processing schemes introduced combine new linear and nonlinear optical platforms such as Fourier-domain programmable optical processors and chalcogenide chip waveguides, as well as the concept of neural network. Transmission of data is considered in the context of medium distance links of Optical Time Division Multiplexed (OTDM) data subject to environmental fluctuations. We experimentally demonstrate simultaneous compensation of differential group delay and multiple orders of dispersion at symbol rates of 640 Gbaud and 1.28 Tbaud. Signal processing at high bandwidth is envisaged both in the case of elementary post-transmission analog error mitigation and in the broader field of optical computing for high level operations (“optical processor”). A key innovation is the introduction of a novel four-wave mixing scheme implementing a dot-product operation between wavelength multiplexed channels. In particular, it is demonstrated for low-latency hash-key based all-optical error detection in links encoded with advanced modulation formats. Finally, the work presents groundbreaking concepts for compact implementation of an optical neural network as a programmable multi-purpose processor. The experimental architecture can implement neural networks with several nodes on a single optical nonlinear transfer function implementing functions such as analog-to-digital conversion. The particularity of the thesis is the new approaches to optical signal processing that potentially enable high level operations using simple optical hardware and limited cascading of components.
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Nguyen, Alex The Phuong. "Short frame wireless communications : new challenges for the physical layer." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0154.
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Les systèmes de communication sans fil à venir vont faire un usage intensif des transmissions de paquets courts. La norme 5G émergente en est un exemple parfait, pour lequel deux des trois principaux cas d'utilisation, les communications massives de type machine (mMTC) et les communications ultra fiables à faible latence (URLLC), reposent intrinsèquement sur des paquets courts. Un autre exemple est fourni par les récents réseaux d'accès de faible puissance (LPWAN) tels que Sigfox, LoRa, etc. et conçus pour prendre en charge l'IoT. L'utilisation de paquets courts au niveau de la couche physique peut modifier considérablement la conception des systèmes de communication numériques. En particulier, avec une longueur de bloc courte, la surcharge de l'en-tête ne peut plus être considérée comme négligeable. Plus important encore, les résultats asymptotiques de la théorie de l'information, qui ont été un guide essentiel et un moteur essentiel de la conception de systèmes de communication en constante amélioration jusqu'à présent, ne sont plus valables dans ce régime. Comment alors assurer une communication fiable sans augmenter la longueur du code puisque ce dernier n'est plus une option? Par extension et plus fondamentalement, comment concevoir la couche physique de paquets courts pour assurer des performances optimales avec l'utilisation la plus efficace possible des ressources disponibles? L'objectif de cette thèse est de revoir les techniques de conception de la couche physique pour la communication par paquets courts et de proposer de nouvelles directives de conception tirant parti des derniers résultats en matière de codage de canal dans le régime de longueur de bloc finieUpcoming wireless communication systems are expected to make intensive use of short packet transmission. An epitome is the emerging 5G standard, for which two out of the three principal use cases, massive Machine Type Communications (mMTC) and Ultra Reliable Low Latency Communications (URLLC), are intrinsically based on short packets. Another example is provided by the recent Low-Power Wide Area Networks (LPWAN) designed to support the IoT such as Sigfox, LoRa, etc.The use of short packets at the physical layer may substantially change the way digital communication systems are designed. In particular, at short block length, header overhead may no longer be considered negligible. More importantly, asymptotic results from information theory which have been a central guide and a key driver to the design of ever-improving communication systems so far no longer hold in this regime. How, then, to ensure reliable communication without increasing the code length since the latter is no longer an option ? By extension and more fundamentally, how to design the physical layer of short packets to ensure optimal performance with the most efficient use of available resources at hand ? The focus of this PhD thesis is to revisit physical layer design for short-packet communication and to propose new design guidelines leveraging the latest results on channel coding in the finite blocklength regime
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Brachmann, Martina [Verfasser], Silvia [Gutachter] Santini, and Thiemo [Gutachter] Voigt. "Highly reliable, low-latency communication in low-power wireless networks / Martina Brachmann ; Gutachter: Silvia Santini, Thiemo Voigt." Dresden : Technische Universität Dresden, 2019. http://d-nb.info/122689660X/34.
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Sonono, Tofik. "Interoperable Retransmission Protocols with Low Latency and Constrained Delay : A Performance Evaluation of RIST and SRT." Thesis, KTH, Kommunikationssystem, CoS, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254897.
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The media industry has during the last decade migrated services from dedicated medianetworks to more shared resources and lately also the public internet and public data centers. Inorder to cater for such transition, several protocols have been designed to meet the demand forhigh-quality media transport over lossy infrastructure, protocols such as SRT and RIST. Thepurpose of Reliable Internet Stream Transport (RIST) and Secure Reliable Transport (SRT) is tohave all vendors of broadcasting equipment support an interoperable way of communication. Thelack of interoperability locks consumers into one particular vendor’s family of products - most oftenthis equipment only supports a proprietary technology. Interoperability creates a more competitivemarket space which benefits consumers and gives vendors an incentive to be more innovative intheir solutions. The purpose of this thesis is to assess the performance of these protocols by comparing theirperformance to a proprietary solution (named ÖÖÖ in this thesis and seen as an establishedsolution in the industry). The challenge is to test these protocols in a lab environment, but have theresults represent real-world use. For this, a large subset of samples is needed along with samplesmeasured over a long period. This sampling was made possible by writing a script which automatesthe sampling process. The results indicate that the versions of RIST and SRT tested in this thesis to some extentcompare well to the selected established protocol (ÖÖÖ). In many scenarios, SRT even did muchbetter, mainly when a line with a single feed was tested. For instance, when the network suffered a2% drop rate and utilized retransmission SRT performed the best and was the only protocol whichhad some samples where no packets were dropped during one hour of measurements. Whenrunning all three protocols at the same time, SRT also did the best in a network with up to 12% droprate. The results in this thesis should give a broadcaster an idea of which of these protocols willfulfill their requirements in a broadcast application.I mediabranschen finns det en efterfrågan på utrustning som har inslag av interoperabilitet.Anledningen till detta är att någon som köper produkter från en viss återförsäljare inte vill låsas in idenna återförsäljares ”ekosystem” i flera år framöver. Då en studio sällan uppgraderar hela sinproduktionskedja på samma gång ger interoperabilitet möjligheten att köpa utrustning från andraåterförsäljare när man ska uppgradera något i produktionslinan. Detta leder till en merkonkurrenskraftig marknad samt ger incentiv till nya innovativa lösningar. Detta examensarbete går ut på att utvärdera lösningar som tagits fram för att främjainteroperabilitet och jämföra dem med en existerande proprietärlösning. Reliable Internet StreamTransport (RIST) och Secure Reliable Transport (SRT) är två protokoll som tagits fram för just dettasyfte. Utmaningen med att utvärdera dessa protokoll är att i en labbmiljö få resultat som reflekteraranvändandet av protokollen i verkligheten. Detta har gjorts med hjälp av ett program som tagitsfram i detta examensarbete. Med detta program har testandet kunnat automatiseras. Resultaten i detta examensarbete visar potential hos båda RIST och SRT. SRT är i vissascenarion till och med bättre än den proprietära lösningen. Protokollen visar något buggigtbeteende i vissa instanser, såsom att i vissa fal sluta fungera och inte kunna återgå till normalfunktion utan manuell interaktion. Allt som allt är dock protokollen i de flesta fallen testade i dettaexamensarbete ett godtyckligt alternativ till den jämförda proprietära lösningen.
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Burleigh, Scott. "TELEMETRY IN BUNDLES: DELAY-TOLERANT NETWORKING FOR DELAY-CHALLENGED APPLICATIONS." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/606730.
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International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, NevadaDelay-tolerant networking (DTN) is a system for constructing automated data networks in which end-to-end communication is reliable despite low data rates, possible sustained interruptions in connectivity, and potentially high signal propagation latency. As such it promises to provide an inexpensive and robust medium for returning telemetry from research vehicles in environments that provide meager support for communications: deep space, the surface of Mars, the poles or the sub- Arctic steppes of Earth, and others. This paper presents an overview of DTN concepts, including “bundles” and the Bundling overlay protocol. One possible scenario for the application of DTN to a telemetry return problem is described, and there is a brief discussion of the current state of DTN technology development.
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Bogadi, Shankar Prasad Mahesh. "Reliable, Low-delay Communication in Wireless Sensor Networks." Thesis, KTH, Reglerteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91931.
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Wireless sensor networks consist of tiny computers embedded into an environment which can monitor almost anything - such as light, motion, proximity, temperature, biometrics and chemical substances. Actuators conjoined to sensor networks can be used not only to sense the environment, but also to interact with it. Such a design is used to develop automatic control systems, ex. a production line in a factory. These systems are delay critical and demand high reliability. Hence wireless sensor networks incorporated into such systems must provide su-cient reliability as well as low delay communication. However, wireless sensors possess power-constrained radios. Furthermore, wireless communication is expensive in terms of power consumption. Wireless link conditions are often harsh, unpredictable and vary considerably in both space, and time. Wireless sensor networks are formed by multi-hop wireless meshes. Consequently, the communication in wireless sensor networks lacks the required reliability, and often exhibits long communication delays. This Master's thesis investigates about the development of a reliable, and low end-to-end delay data collection scheme for wireless sensor networks. The approach is to decrease the number of retransmissions for a packet at the data link layer in order to decrease the end-to-end delay. However, a decrease in the number of retransmissions for a packet leads to lower reliability. In order to compensate for the reliability suered, an erasure coding scheme, and a multipath routing paradigm are investigated. Accordingly, the thesis focuses on an implementation, and evaluation of an e-cient combination of fountain coding, braided multi-path routing, and proportionally fair packet scheduling. The thesis concludes that fountain coding in combination with braided multipath routing and proportionally fair packet scheduling is an e-cient solution for a wireless sensor network with high loss rates.
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Prevost, Janelle Kenty-Joan 1978. "A reliable low bandwidth email-based communication protocol." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86698.
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Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 69).
by Janelle Kenty-Joan Prevost.
M.Eng.and S.B.
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Contreras, Andres A. "Micronetworking: Reliable Communication on 3D Integrated Circuits." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/728.
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The potential failure in through-silicon vias (TSVs) still poses a challenge in trying to extend the useful life of a 3D integrated circuit (IC). A model is proposed to mitigate the communication problem in 3D integrated circuits caused by the breaks at the TSVs. We provide the details of a low-complexity network that takes advantages of redundant TSVs to make it possible to re-route around breaks and maintain effective communication between layers. Different configurations for the micronetwork are analyzed and discussed. We also present an evaluation of the micronetwork's performance, which turns out to be quite promising, based on several Monte Carlo simulations. Finally, we provide some directions for future research on the subject.
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RICCIUTELLI, GIACOMO. "Modern coding techniques for reliable and secure communications." Doctoral thesis, Università Politecnica delle Marche, 2018. http://hdl.handle.net/11566/252896.
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Oggigiorno, le comunicazioni wireless sono coinvolte in molte applicazioni e gli obiettivi di sicurezza e affidabilità sono sempre più stringenti. Perciò, in questa tesi vengono proposte nuove soluzioni basate su schemi di codifica moderni in grado di conseguire prestazioni sempre più soddisfancenti. Adottiamo codici Low Density Parity Check (LDPC) e codici polari.
Per la versatilità dei codici LDPC, li utilizziamo sia per scopi di affidabilità che di sicurezza.
Un canale wire-tap è caratterizzato da un intercettatore che tenta di decodificare le informazioni inviate tra ricevitori autorizzati. In questo scenario, seguendo un approccio di Physical Layer Security, analizziamo il tasso di equivocazione degli intercettatori raggiunto tramite schemi LDPC pratici.
Generalizzando questo modello con un canale broadcast con messaggi confidenziali, progettiamo codici LDPC con protezione non uniforme degli errori al fine di migliorare la privacy dei dati.
Invece, per scopi di affidabilità, utilizziamo i codici LDPC su un canale satellitare non convenzionale come quello influenzato dalla scintillazione solare. In questo contesto, il rumore introdotto dai fenomeni fisici può portare a una scarsa qualità della comunicazione. Perciò, proponiamo schemi di codifica che migliorano l'affidabilità del collegamento.
Infine, studiamo sistemi di comunicazione con trasmissione di blocchi corti. In questo caso utilizziamo i codici polari poiché sono una delle famiglie di codici più importanti in questo scenario. Tuttavia, con pacchetti corti, i codici polari possono avere scarse prestazioni. Per questo motivo in letteratura è stata proposta la loro concatenazione con un codice ciclico. I codici polari concatenati diventano competitivi in questo contesto e pertanto sono stati raccomandati per la nuova generazione di sistemi mobili (5G). Studiando lo spettro dei pesi degli schemi concatenati, proponiamo alcune soluzioni in grado di migliorare ulteriormente l'affidabilità della comunicazione.Nowadays, wireless communications are involved in many applications and the security and reliability targets are increasingly growing. Hence, based on modern coding schemes, in this thesis new solutions able to achieve more and more satisfactory performance are proposed. In particular, we adopt Low Density Parity Check (LDPC) codes and Polar Codes. Due to the versatility of LDPC codes, we use this codes family for both reliability and security scopes. A wire-tap channel is characterized by an eavesdropper that tries to decode the information sent among authorized receivers. In this scenario, by following the physical layer security approach, first we investigate the eavesdropper's equivocation rate achieved through practical LDPC schemes. Then, by generalizing this model with a broadcast channel with confidential messages, we design LDPC codes with unequal error protection capabilities that improve the privacy of data. Instead, for reliability purposes, we use LDPC codes over a non-conventional satellite channel like the one affected by solar scintillation. In this context, the noise introduced by physical phenomena may lead to a low quality in the communication. Hence, by mitigating the performance degradation, in this thesis we propose coding schemes that improve the link reliability. Finally, we study communication systems based on the transmission of short blocks. In this case we use Polar codes since they are one of the most prominent codes family proposed for this scenario. However, in the short packet length regime Polar codes may have poor performance. To overcome this issue, a concatenation with a cyclic code was proposed in the literature. Concatenated Polar codes are competitive in this context and therefore they are recommended in the new generation of mobile systems (5G). Thus, we study the structure of these concatenated schemes from a distance spectrum point of view and propose some solutions able to further improve the reliability of communication.
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Weisenhorn, Martin. "Low-complexity techniques for ultra-wideband communication systems." kostenfrei, 2007. http://mediatum2.ub.tum.de/doc/625801/document.pdf.
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He, Yin. "Ultra low profile VHF antennas for M2M communications via satellite." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57840.
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Government transport regulations and practical considerations limit the height of terminal antennas used in satellite-based mobile asset tracking applications to less than 2.5 cm. For Orbcomm systems that operate at 138 MHz (downlink) and 150 MHz (uplink), this implies an antenna that is just over one-hundredth of a wavelength tall. Achieving good efficiency and operating bandwidth with such an ultra low profile antenna is fundamentally difficult. Here we consider the possibility of using a multi-arm normal mode cylindrical helix antenna to achieve a significant fraction of the performance of a full size Orbcomm reference antenna in a more compact form. In order to simplify impedance matching, we introduced an internal magnetic coupling loop that can be increased or decreased in radius in order to achieve a good match. In order to identify the optimum design, we assessed the radiation efficiency and bandwidth of the antenna as a function of the key design parameters (helix height, radius, number of arms, number of turns, feed loop radius, presence or absence of crossbars that connect the arms at the top of the helix) using simulations and validated the results by measuring the performance of selected hardware prototypes. Further, we developed an equivalent circuit model that allows one to extract key design information much more quickly than would be possible by simulation or measurement. Our design curves show that bandwidth can only be increased with height and is independent of radius at ULP height. We found that efficiency increased significantly with helix radius but the presence of crossbars yielded only a marginal increase in efficiency. A pair of ULP antennas is required for uplink and downlink. To connect two such antennas to a standard Orbcomm modem with a single antenna port, we considered three duplexer designs: a carrier operated relay, a diplexer filter, and a novel complementary feed. The latter is both simpler and more effective than the first two. Over a 72-hour period, our best ULP antenna design (four arms, no cross bar, helix radius ~0.04 wavelengths) was able to exchange 45% of the messages that a standard Orbcomm reference antenna could.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Webber, Scott. "Design of Ultra Wideband Low Noise Amplifier for Satellite Communications." Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1703346/.
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This thesis offers the design and improvement of a 2 GHz to 20 GHz low noise amplifier (LNA) utilizing pHEMT technology. The pHEMT technology allows the LNA to generate a boosted signal at a lower noise figure (NF) while consuming less power and achieving smooth overall gain. The design achieves an overall gain (S21) of ≥ 10 dB with an NF ≤ 2 dB while consuming ≤ 30 mA of power while using commercial off-the-shelf (COTS) components.
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Wallmeier, Jonas. "RDS-Based Intersystem Communication for Ultra-Low Data Platoon VANETs." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235623.
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Many experts agree that Vehicular Ad Hoc Networks (VANETs) are indis- pensable for the future of our transportation system. The applications that could be based on this technology are endless and stretch from automated breaking systems to multimedia streaming. However, current approaches all rely on additional hardware which is not available in modern off-the-shelf vehicles. This document aims to explore the feasibility of using the Radio Data System (RDS) standard, which is supported by all modern car radios, for forming Vehicular Ad Hoc Networks.Många experter är överens om att Vehicular Ad Hoc Networks (VANETs) är indis- penslar för framtiden för vårt transportsystem. De applikationer som kan baseras på denna teknik är oändliga och sträcker sig från automatiserad bryta system till multimedia streaming. Men nuvarande metoder är alla beroende av extra hårdvara som inte är Finns i moderna fordon utan hylla. Detta dokument syftar till att undersöka möjligheten att använda radiodatasystemet (RDS) standard, som stöds av alla moderna bilradioer, för bildning Vehicular Ad Hoc Networks.
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Idris, Izwan. "Real-time vehicle monitoring and positioning using MQTT for reliable wireless connectivity." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/106921/1/Izwan_Idris_Thesis.pdf.
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This project was aimed at developing affordable solutions to improve performances of real-time monitoring of road vehicles utilizing low-cost satellite positioning equipment and wireless cellular communication network. This study investigates the problems by measuring and benchmarking two-way communication latency, data reliability and positioning accuracy using low-cost GPS equipment and a lightweight machine-to-machine (M2M) protocol called Message Queue Transmission Telemetry (MQTT). A prototype of vehicle monitoring platform which consists of on-board-unit and central monitoring server was developed to facilitate the research study.
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Maldari, Mirko. "Design of an ultra-low-power communication system for leadless pacemaker synchronization." Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAT018.
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L’objectif de nos études était de proposer des solutions optimisées pour la communication entre pacemakers sans sondes (LCP en Anglais) afin de permettre la synchronisation de la thérapie entre dispositifs implantés dans des chambres cardiaques différentes. L’Intra-Body Communication (IBC) est considérée comme une solution prometteuse. Il s’agit d’une communication qui utilise les tissue biologiques comme moyen de transmission. Les atténuations des canaux de communication ont été caractérisé en utilisant un model de thorax vérifié grâce à des essais in vivo. Un récepteur à très faible consommation a été conçu en technologie CMOS avec une sensitivité qui respecte les niveaux des signaux issus de la caractérisation du canal intra-cardiaque. Afin de minimiser la consommation du récepteur et, en conséquence, réduire l’impacte du circuit en termes de longévité du dispositif, une stratégie innovante de communication a été proposée. Les résultats de recherche démontrent la faisabilité d’une synchronisation entre LCPs fondée sur télémétrie, ouvrant la voie à la réalisation de systèmes multi-dispositifs pour améliorer la qualité du traitement de patients qui souffrent de bradycardie. Ce travail fait partie du projet WiBEC, un projet multidisciplinaire qui vise à concevoir des technologies sans fils pour des dispositifs implantablesOur research focused on power optimized solutions for the communication between Leadless Cardiac Pacemakers (LCP) to allow a synchronized therapy among devices implanted in different cardiac chambers. A promising solution is the Intra-Body Communication (IBC), which uses biological tissues as transmission medium. The attenuation of the communication channels were characterized using an accurate torso model that has been verified by means of in-vivo experiments. An ultra-low power receiver has been designed in CMOS technology according to the sensitivity requirement coming from the intra-cardiac channel characterization. Moreover, a novel communication strategy has been proposed to minimize the power consumption of the receiver reducing the impact in terms of device longevity. The research results show the feasibility of a telemetry driven synchronization of LCPs, paving the way toward multiple-leadless pacemaker systems that might improve the quality of treatment of the bradycardia patients. This work was part of the WiBEC project. It is a multi-disciplinary project aiming to develop the wireless technologies for novel implantable devices
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Vecchia, Davide. "Energy-efficient, Large-scale Ultra-wideband Communication and Localization." Doctoral thesis, Università degli studi di Trento, 2022. http://hdl.handle.net/11572/349081.
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Among the low-power wireless technologies that have emerged in recent years, ultra-wideband (UWB) has successfully established itself as the reference for accurate ranging and localization, both outdoors and indoors. Due to its unprecedented performance, paired with relatively low energy consumption, UWB is going to play a central role in the next wave of location-based applications. As the trend of integration in smartphones continues, UWB is also expected to reach ordinary users, revolutionizing our lives the same way GPS and similar technologies have done. But the impact of UWB may not be limited to ranging and localization. Because of its considerable data rate, and its robustness to obstacles and interference, UWB communication may hold untapped potential for sensing and control applications. Nevertheless, several research questions still need to be answered to assess whether UWB can be adopted widely in the communication and localization landscapes. On one hand, the rapid evolution of UWB radios and the release of ever more efficient chips is a clear indication of the growing market for this technology. However, for it to become pervasive, full-fledged communication and localization systems must be developed and evaluated, tackling the shortcomings affecting current prototypes. UWB systems are typically single-hop networks designed for small areas, making them impractical for large-scale coverage. This limitation is found in communication and localization systems alike. Specifically for communication systems, energy-efficient multi-hop protocols are hitherto unexplored. As for localization systems, they rely on mains-powered anchors to circumvent the issue of energy consumption, in addition to only supporting small areas. Very few options are available for light, easy to deploy infrastructures using battery-powered anchors. Nonetheless, large-scale systems are required in common settings like industrial facilities and agricultural fields, but also office spaces and museums. The general goal of enabling UWB in spaces like these entails a number of issues. Large multi-hop infrastructures exacerbate the known limitations of small, single-hop, networks; notably, reliability and latency requirements clash with the need to reduce energy consumption. Finally, when device mobility is a factor, continuity of operations across the covered area is a challenge in itself. In this thesis, we design energy-efficient UWB systems for large-scale areas, supporting device mobility across multi-hop infrastructures. As our opening contribution, we study the unique interference rejection properties of the radio to inform our design. This analysis yields a number of findings on the impact of interference in communication and distance estimation, that are directly usable by developers to improve UWB solutions.
These findings also suggest that concurrent transmissions in the same frequency channel are a practical option in UWB. While the overlapping of frames is typically avoided to prevent collisions, concurrent transmissions have counter-intuitively been used to provide highly reliable communication primitives for a variety of traffic patterns in narrowband radios. In our first effort to use concurrent transmissions in a full system, we introduce the UWB version of Glossy, a renowned protocol for efficient network-wide synchronization and data dissemination. Inspired by the success of concurrency-based protocols in narrowband, we then apply the same principles to define a novel data collection protocol, Weaver. Instead of relying on independent Glossy floods like state-of-the-art systems, we weave multiple data flows together to make our collection engine faster, more reliable and more energy-efficient. With Glossy and Weaver supporting the communication aspect in large-scale networks, we then propose techniques for large-scale localization systems. We introduce TALLA, a TDoA solution for continuous position estimation based on wireless synchronization. We evaluate TALLA in an UWB testbed and in simulations, for which we replicate accurately the behavior of the clocks in our real-world platforms. We then offer a glimpse of what TALLA can be employed for, deploying an infrastructure in a science museum to track visitors. The collected movement traces allow us to analyze fine-grained stop-move mobility patterns and infer the sequence of visited exhibits, which is only possible because of the high spatio-temporal granularity offered by TALLA. Finally, with SONAR, we tackle the issue of large-scale ranging and localization when the infrastructure cannot be mains-powered. By blending synchronization and scheduling operations into neighbor discovery and ranging, we drastically reduce energy consumption and ensure years-long system lifetime. Overall, this thesis enhances UWB applicability in scenarios that were previously precluded to the technology, by providing the missing communication and localization support for large areas and battery-powered devices. Throughout the thesis, we follow an experiment-driven approach to validate our protocol models and simulations. Based on the evidence collected during this research endeavor, we develop full systems that operate in a large testbed at our premises, showing that our solutions are immediately applicable in real settings.
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Raza, Saleem [Verfasser], and Mesut [Gutachter] Güneş. "Medium Access Control protocols for reliable communication in low-power industrial applications / Saleem Raza ; Gutachter: Mesut Güneş." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2020. http://d-nb.info/1219965030/34.
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Raza, Saleem Verfasser], and Mesut [Gutachter] [Güneş. "Medium Access Control protocols for reliable communication in low-power industrial applications / Saleem Raza ; Gutachter: Mesut Güneş." Magdeburg : Universitätsbibliothek Otto-von-Guericke-Universität, 2020. http://d-nb.info/1219965030/34.
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RICCARDI, DOMENICO. "Ultra-Low Phase Noise VCOs in SiGe BiCMOS for high-capacity and spectrally-efficient mmWave communications." Doctoral thesis, Università degli studi di Pavia, 2022. http://hdl.handle.net/11571/1454406.
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The ever-growing mobile data traffic drives continuous innovations in wireless communications, and the development of new generation mobile network is expected to provide ultra-high data rates. However, the use of spectrally efficient high-order modulations sets stringent phase-noise requirements to frequency synthesizers in the network infrastructure.
In this framework, this thesis addresses the challenge of achieving a remarkable advance in the state-of-the-art phase-noise performance of silicon oscillators. First it recognized that given the supply voltage, the phase noise in LC oscillators is reduced by scaling down the inductance and increasing power consumption. However, the Q degradation with too small inductors sets a lower bound on phase noise. To overcome this limit, oscillators evolved from a single core to multi-core, with N oscillators coupled to scale down phase noise ideally by 10 log(N). In this dissertation, two different coupling techniques are compared: active-coupling (i.e., by means of transconductors) and resistive-coupling (i.e., by means of resistors), that is the two most promising topologies to implement a reconfigurable solution by turning on/off oscillators and the coupling stages to scale noise and power consumption. A theoretical analysis of dual-core oscillators examines the mechanism of phase-noise scaling with specific focus on the degradation caused by resonant frequency mismatches between the LC-tanks, proving that resistive-coupling is the more robust coupling technique. The extension to N oscillators, with N >2, is then considered, demonstrating the existing tradeoff between increasing the number N of coupled oscillators and the locking capability, together with the phase noise penalty in presence of resonant frequency mismatches. Closed-form formulas of the locking range and the statistical phase noise degradation, provide deep understanding of the coupling requirements and useful insights on coupled oscillators design.
Test-chips of a 20 GHz 16-core class-C VCO is fabricated in 55nm SiGe BiCMOS technology. Measurements demonstrate a record phase noise as low as -130 dBc/Hz at 1MHz offset, at least 8dB lower than state-of -the-art. Power consumption is 840mW, corresponding to 186.6 dBc/Hz Figure of Merit (FoM), while the tuning range is 17.4%. A reconfigurable version of the multi-core oscillator is realized exploiting DC-biased diode-connected bipolar transistors as switches to couple oscillators. Measurements at 1MHz offset from the 19.2GHz carrier show -120dBc/Hz phase noise in dual-core configuration which can be lowered down to -128.8dBc/Hz turning on two-by-two up to 16 resonators. Meanwhile, the power dissipated from the 2.4V supply ranges between 105mW to 948mW. A different approach is finally introduced in this thesis: a technique which breaks the phase noise barrier of conventional LC oscillators. By exploiting the series resonance of a tank, an unprecedent phase noise reduction in a single-core oscillator is experimentally demonstrated. Realized in a 55nm-BiCMOS technology, the series-resonance VCO proves -138dBc/Hz phase noise at 1MHz offset from 10GHz, with 600mW power consumption from 1.2V supply, corresponding to a state-of-the-art 190dBc/Hz FoM. This phase noise is at least 10dB lower than what reported in silicon so far.
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Enriquez, Karla Cecilia. "Development of an ultra-low power sensor for highway health monitoring." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Tauqeer, Tauseef. "Low Power, High Speed InP-Based Digital Intergrated Circuits for Ultra Wide Band Communicatiopn Systems." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508526.
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Lee, Hyung-Jin. "Digital CMOS Design for Ultra Wideband Communication Systems: from Circuit-Level Low Noise Amplifier Implementation to a System-Level Architecture." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/26195.
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CMOS technology is particularly attractive for commercialization of ultra wideband (UWB) radios due to its low power and low cost. In addition to CMOS implementation, UWB radios would also significantly benefit from a radio architecture that enables digital communications. In addition to the normal challenges of CMOS RFIC design, there are two major technical challenges for the implementation of CMOS digital UWB radios. The first is building RF and analog circuitry covering wide bandwidth over several GHz. The second is sampling and digitizing high frequency signals in the UWB frequency range of 3 GHz to 10 GHz, which is not feasible for existing CMOS analog-to-digital converters.
In this dissertation, we investigate the two technical challenges at the circuit level and the system level. We propose a systematic approach at the circuit level for optimal transistor sizing and biasing conditions that result in optimal noise and power matching over a wide bandwidth. We also propose a general scheme for wideband matching. To verify our methods, we design two single-stage low noise amplifiers (LNAs) in TSMC 0.18µm CMOS technology. Measurement results from fabricated chips indicate that the proposed LNAs could achieve as high as 16 dB power gain and as low as 2.2 dB noise figure with only 6.4 mA current dissipation under a supply voltage of 1.2 V.
At the system level, we propose a unique frequency domain receiver architecture. The receiver samples frequency components of a received signal rather than the traditional approach of sampling a received signal at discrete instances in time. The frequency domain sampling leads to a simple RF front-end architecture that directly samples an RF signal without the need to downconvert it into a baseband signal. Further, our approach significantly reduces the sampling rate to the pulse repetition rate. We investigate a simple, low-power implementation of the frequency domain sampler with 1-bit ADCs. Simulation results show that the proposed frequency-domain UWB receiver significantly outperforms a conventional analog correlator.
A digital UWB receiver can be implemented efficiently in CMOS with the proposed LNA as an RF front-end, followed by the frequency domain sampler.Ph. D.
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Muppalla, Ashwin K. "Ultra low power multi-gigabit digital CMOS modem technology for millimeter wave wireless systems." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/41084.
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The objective of this research is to present a low power modem technology for a high speed millimeter wave wireless system.
The first part of the research focuses on a robust ASIC design methodology. There are several aspects of the ASIC flow that require special attention such as logical synthesis, timing driven physical placement, Clock Tree Synthesis,
Static Timing Analysis, estimation and reduction of power consumption and LVS and DRC closure.
The latter part is dedicated to high speed baseband circuits such as Coherent and Non coherent demodulator which are critical components of a multi-gigabit wireless communication system. The demodulator operates at input data rates of multiple gigabits per second, which presents the challenge of designing the building blocks to operate at speeds of multiple GHz. The high speed complex multiplier is a major component of the non coherent demodulator. As part of the coherent demodulator the complex multiplier derotates the input sequence by multiplying with cosine and sine functions, Costas error calculator computes the phase error in the derotated input signal. The NCO (Numerically controlled Oscillator) is a look up table based system used to generate the cosine and sine functions, used by the derotator.The CIC filter is used to decimate the costas error signal as the loop bandwidth is significantly smaller compared to the sampling frequency. All these modules put together form the coherent demodulator which is an integral part of the wireless communication system. An implementation of Serdes is also presented which acts as an interface between the baseband modules and the RF front end.
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Gebreyohannes, Fikre Tsigabu. "Design of Ultra-Low Power Wake-Up Receiver in 130nm CMOS Technology." Thesis, Linköpings universitet, Elektroniksystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78797.
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Wireless Sensor Networks have found diverse applications from health to agriculture and industry. They have a potential to profound social changes, however, there are also some challenges that have to be addressed. One of the problems is the limited power source available to energize a sensor node. Longevity of a node is tied to its low power design. One of the areas where great power savings could be made is in nodal communication. Different schemes have been proposed targeting low power communication and short network latency. One of them is the introduction of ultra-low power wake-up receiver for monitoring the channel. Although it is a recent proposal, there has been many works published. In this thesis work, the focus is study and comparison of architectures for a wake-up receiver. As part of this study, an envelope detector based wake-up receiver is designed in 130nm CMOS Technology. It has been implemented in schematic and layout levels. It operates in the 2.4GHz ISM band and consumes a power consumption of 69µA at 1.2V supply voltage. A sensitivity of -52dBm is simulated while receiving 100kb/s OOK modulated wake-up signals.This is a master's thesis work by a communication electronics student in a German company called IMST GmbH.
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Huang, An-Lun. "Security primitives for ultra-low power sensor nodes in wireless sensor networks An-Lun (Alan) Huang." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-05052008-110318/.
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Hauer, Jan-Hinrich [Verfasser], Adam [Akademischer Betreuer] Wolisz, Roberto [Akademischer Betreuer] Verdone, and Rolf [Akademischer Betreuer] Kraemer. "Towards reliable communication in low-power wireless body area networks / Jan-Hinrich Hauer. Gutachter: Adam Wolisz ; Roberto Verdone ; Rolf Kraemer. Betreuer: Adam Wolisz." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065669453/34.
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Vauché, Rémy. "Conception de générateurs d'impulsions ultra-large bande en technologie CMOS." Thesis, Aix-Marseille 1, 2011. http://www.theses.fr/2011AIX10098.
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La théorie de l'information développée par Claude Shannon (1916 - 2001) met en évidence le fait que pour accroître la capacité d'un canal de transmission, il est préférable d'élargir la bande de fréquences sur laquelle les informations sont émises plutôt que les puissances d'émissions. Cette constatation est le point de départ de nombreux travaux de recherche sur les communications Ultra-Large Bande (ULB) qui ont abouti en 2002 à la création aux Etats-Unis d'une bande fréquence dîtes ULB où aucun mode de communication n'est privilégié. C'est ainsi que 2 années plus tard ont débuté à l'IM2NP des travaux portant sur les communications ULB impulsionnelles, et notamment la conception d'amplificateur faible bruit, de détecteur d'énergie, mais également de générateurs d'impulsions qui est l'élément clé des émetteurs impulsionnels. Ces derniers constituent la base des travaux présentés dans le manuscrit qui se sont déroulés de 2008 à 2011. La nature discontinue des communications impulsionnelles a tout d'abord impliquée l'introduction de nouvelles figures de mérite permettant de mesurer les performances des générateurs d'impulsions. Ensuite, il est question de méthodes de conception permettant de dimensionner des structures fonctionnant aux fréquences en jeu mais également d'en réduire les consommations statiques principalement de fuite, et ce en vue de répondre aux contraintes de consommation des systèmes embarqués. Enfin sont développées 3 architectures de générateurs d'impulsions, chacune permettant de répondre à des contraintes différentes en termes de bande de fréquences, de consommation et de portéeThe information theory developed by Claude Shannon (1916 - 2001) highlights the fact that in order to increase the capacity of a transmission channel, it is preferable to extend the bandwidth used rather than the transmission power. This finding is the starting point of many papers on Ultra-Wideband (UWB) which led to the creation in the United States of UWB band since 2002 where no modulation is privileged. Two years later, many works on Impulsionnal Radio UWB (IR-UWB) communications began at IM2NP including the design of low noise amplifier, power detector, but also pulse generators which is the key element of IR-UWB emitters. These form basis of works presented in the manuscript that took place from 2008 to 2011. The discontinuous nature of communications impulse was first implied the introduction of new figures of merit for measuring performances of pulse generators. Then it deals with design techniques for sizing structures operating at frequencies involved, but also to reduce consumption and especially static leakage to reduce enough power consumption for embedded systems. Finally three architectures of pulse generators are developed, each one responding to different constraints in terms of frequency, consumption and range
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Monti, Michele. "Ottimizzazione di sistemi Wake-Up Radio per applicazioni RFID basate su microcontrollori ultra-low power." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13265/.
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Oggetto di studio di questa tesi di laurea è la realizzazione di un firmware dedicato alla sezione logica di controllo di una Wake-up Radio implementata su tag RFID, realizzata attraverso l'utilizzo di un microcontrollore ultra-low power.
Per la realizzazione del sistema, si é deciso di utilizzare il microcontrollore Apollo prodotto da Ambiq Micro.
Tale dispositivo, basandosi sull'architettura Subthreshold Power Optimized Technology (SPOT) brevettata da Ambiq, utilizza transistori polarizzati in regione di sottosoglia, presentando i migliori valori di consumo dichiarati sul mercato.
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Eriksson, Gustav. "Towards Long-Range Backscatter Communication with Tunnel Diode Reflection Amplifiers." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354901.
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Backscatter communication enables wireless communication at a power consumption orders of magnitude lower than conventional wireless communication. Instead of generating new RF-signals backscatter communication leverages ambient signals, such as WiFi-, Bluetooth- or TV-signals, and reflects them by changing the impedance of the antenna. Backscatter communication is known as a short-range communication technique achieving ranges in the order of meters. To improve the communication range, we explore the use of a tunnel diode as an amplifier of the backscattered RF-signal. We developed the amplifier on a PCB-board together with a matching network tuned to give maximum gain at 868 MHz. Our work demonstrates that the 1N3712 tunnel diode can achieve gains up to 35 dB compared to a tag without amplification while having a peak power consumption of 48 μW. With this amplifier the communication distance can be increased by up to two orders of magnitude.
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Goratti, L. (Leonardo). "Design, analysis and simulations of medium access control protocols for high and low data rate applications." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514296512.
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Abstract The past two decades have witnessed an unprecedented proliferation of mobile devices equipped with extremely innovative wireless technologies. Short range networks, such as wireless personal area networks (WPANs), wireless sensor networks (WSNs) and wireless body area networks (WBANs) have been defined and researched to deliver high speed home connectivity, environment and health monitoring. This thesis tackles design, analysis and simulation of medium access control (MAC) protocols tailored for short range networks. These have in common the use of battery operated devices but also certain design challenges connected with MAC protocols are common upon selecting the physical layer technology. Ultra wideband (UWB) technology and 60 GHz technology (which is referred to also as millimeter wave communications) are two valid examples of the wireless revolution of the past decade. Several existing standards, such as IEEE 802.15.3, ECMA-368, IEEE 802.15.4 and its amendment IEEE 802.15.4a, are considered in this thesis for MAC analysis in conjunction with UWB technology. With regard to millimeter wave communications the characteristics of the IEEE 802.15.3c standard are taken into account. Apart for the IEEE 802.15.3c all the MAC protocols have been modeled in the network simulator Opnet. One contribution of this thesis is to produce an innovative and in-depth analysis of the management aspects (e.g. ECMA-368 distributed beaconing) stemming from the above mentioned standards by means of analytical and simulation models. This study approach allows selecting the MAC features suitable for the applications and the technologies of interest. The key performance metric used to analyze all the protocols is energy efficiency, but also throughput is investigated. Another contribution brought by this thesis consists in the innovative way of studying slotted-based MAC protocols as an integrated concept connected with the type of network, the type of application and the selected physical technologies. This thesis also shows MAC performance in conjunction with UWB when false alarm, miss-detection and receiver capture (capture is modeled by means of an existing interference model) are taken into consideration. Most of the unrealistic, though common, assumptions in MAC analysis are removed and the performance of selected medical applications is evaluated through Opnet simulations. The well known binary exponential backoff is analyzed with an innovative though simplified one-dimensional Markov chain approach in the context of directional MAC for 60 GHz communications. As shown in the remainder of this thesis, the simplification introduced does not hinder the accuracy of the results, but rather allows accounting even for a finite number of retransmissions with a simple chain extensionTiivistelmä Kahden viime vuosikymmenen aikana innovatiivisella langattomalla tekniikalla varustettujen viestintälaiteiden määrä on kasvanut räjähdysmäisesti. Lyhyen kantaman verkkoja kuten langattomia henkilökohtaisen alueen verkkoja (WPAN), langattomia anturiverkkoja (WSN) ja langattomia vartaloalueen verkkoja (WBAN) on määritelty ja tutkittu, jotta voitaisiin tuottaa korkeanopeuksisia kotiyhteyksiä sekä välineitä ympäristön ja terveydentilan seurantaan. Tämä väitöskirja käsittelee lyhyen kantaman viestintään suunniteltujen linkinohjauskerroksen MAC-protokollien suunnittelua, analysointia ja simulointia. Näissä kaikissa käytetään akkukäyttöisiä laitteita, mutta myös tietyt MAC-protokollien suunnittelun haasteet ovat tavallisia fyysisen kerroksen teknologiaa valittaessa. Ultra-laajakaistainen (UWB) teknologia ja 60 GHz teknologia (eli millimetriaallonpituusalueen tietoliikenne) ovat hyviä esimerkkejä kuluneen vuosikymmenen langattomasta vallankumouksesta. Tässä väitöskirjassa huomioidaan UWB teknologiaan liittyvää MAC-kerroksen analyysiä tehtäessä useat olemassa olevat standardit, kuten IEEE 802.15.3, ECMA-368, IEEE 802.15.4 ja sen lisäys IEEE 802.15.4a. Millimetriaallonpituusalueen tietoliikenteessä huomioidaan myös IEEE 802.15.3c standardin erityispiirteet. IEEE 802.15.3c:tä lukuun ottamatta kaikki MAC-protokollat on mallinnettu Opnet verkkosimulaattorilla. Tämä tutkimus tarjoaa innovatiivisen ja syväluotaavan tutkimuksen näiden standardien pohjalta ja analyyttisten ja simuloitujen mallien avulla kehitetyistä hallinnallisista lähestymistavoista (esim. ECMA-368 hajautettu majakkasignaali). Näiden avulla voidaan valita kohteena oleviin sovelluksiin ja teknologioihin parhaiten soveltuvia MAC-ominaisuuksia. Kaikkien protokollien analysointiin käytetty ensisijainen suorituskykymittari on energiatehokkuus, mutta myös datanopeuksia on tarkasteltu. Tässä tutkimuksessa esitellään myös innovatiivinen tapa tutkia MAC protokollia integroituina konsepteina suhteessa verkon ja sovellusten tyyppiin sekä fyysisen kerroksen teknologiaan. Lisäksi tämä väitöskirja esittelee MAC suorituskykyä UWB verkossa silloin, kun siinä otetaan huomioon väärät hälytykset, väärä havainnointi ja vastaanottimen signaalinkaappaus (vastaanoton mallintamiseksi käytetään olemassa olevaa interferenssimallia). MAC analyysistä poistetaan useimmat epärealistiset, vaikkakin tavalliset, olettamukset, ja verkkojen suorituskykyä tarkastellaan valittujen kriittisten parametrien monitoroinnissa Opnet-simulaatioiden avulla. Tunnettua binäärijakoinen eksponentiaalinen perääntyminen -algoritmia analysoidaan innovatiivisella, yksinkertaistetulla yksiulotteisella Markov-ketju -mallilla 60 GHz:n suunta-antenni MAC:n yhteydessä. Kuten tässä tutkimuksessa tullaan osoittamaan, esitelty yksinkertaistus ei rajoita tulosten tarkkuutta, vaan mukaan voidaan lukea jopa rajallinen määrä uudelleenlähetyksiä yksinkertaisen Markovin ketjun laajennuksen avulla
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Haloua, Abderrahmane. "Étude d’un protocole de communication asynchrone faible consommation à lien radio impulsionnel ultra-large bande : implémentation sur silicium des fonctions RF critiques." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0255.
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Au cours des dernières années, différents travaux de recherche ont été consacrés à l’étude et au développement des solutions de type réseau de capteurs sans fil. Ces travaux sont une réponse à l’augmentation du nombre d’objets connectés dans le monde avec le développement de l’internet des objets. La consommation d’énergie dans les réseaux de capteurs représente un des domaines les plus étudiés. Les communications dans les réseaux de capteurs représentent une part importante de leur consommation. Afin de réduire la consommation des communications dans les réseaux de capteurs, différents niveaux d’optimisation sont possibles. Dans ce contexte, différents travaux de recherches visant à réduire la consommation des émetteurs-récepteurs, grâce à des architectures innovantes, ont été menés à l’IM2NP. Beaucoup de ces travaux ont été consacrés aux radios impulsionnelles Ultra-Large Bande (ULB). En outre, les protocoles d’accès aux canaux de communications dans les réseaux de capteurs sont également importants quant à l’optimisation de leurs consommations. Les travaux de recherches proposés dans ce manuscrit, basés sur les travaux sur les radios impulsionnelles ULB réalisés au sein de l’IM2NP, proposent une optimisation de la consommation des réseaux de capteurs sur deux niveaux. Tout d’abord, un protocole asynchrone à base de radio de réveil d’accès au canal de communication adapté aux communications ULB est proposé ainsi que son étude énergétique. Suite à l'étude du protocole asynchrone proposé, la conception d’un récepteur de réveil semi-passif et d’un générateur d’impulsion ULB sous-GHz est abordée, et leurs performances en termes d’efficacité énergétique discutéesIn recent years, research has been devoted to the study and development of Wireless Sensor Network (WSN). These research are a response to the increase of the connected objet number in the world with development of smartphones and Internet of things (IoT). Energy consumption in sensor networks is one of the most studied areas. In fact, the optimization of the consumption of the elements making up the sensor networks allows a reduction in the costs associated with their installation, operation and maintenance. Communications in sensor networks represent an important part of their power consumption. In order to reduce the consumption of communications in sensor networks, different levels of optimization are possible. In this context, various IM2NP research projects aimed at reducing transceiver consumption through innovative design were carried out. Much of this work has been devoted to Impulsionnal Radio Ultra-Wide Band (IR-UWB). Moreover, MAC protocols used to manage the communication channel access in wireless sensor networks are also important in optimizing their consumption. The research work proposed in this manuscript, based on the work on impulse radios UWB carried out within the IM2NP, propose an optimization of the consumption of sensor networks on two levels. Firstly, an asynchronous MAC protocol based on radio wake-up radio suitable for UWB communications is proposed as well as its energy study. Following the study of the proposed asynchronous protocol, the design of a low power semi-passive wake-up receiver (WuRx) and a UWB sub-GHz impulse generator is presented and their performance in terms of energy efficiency discussed
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Liendo, sanchez Andreina. "Study of adaptation mechanisms of the wireless sensor nodes to the context for ultra-low power consumption." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT095/document.
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L'Internet des objets (IoT) est annoncé comme la prochaine grande révolution technologique où des milliards d'appareils s'interconnecteront en utilisant les technologies d’Internet et permettront aux utilisateurs d'interagir avec le monde physique, permettant Smart Home, Smart Cities, tout intelligent. Les réseaux de capteurs sans fil (WSN) sont cruciales pour tourner la vision de l'IoT dans une réalité, mais pour que cela devienne réalité, beaucoup de ces dispositifs doivent être autonomes en énergie. Par conséquent, un défi majeur est de fournir une durée de vie de plusieurs années tout en alimentant les nœuds par batteries ou en utilisant l'énergie récoltée. Bluetooth Low Energy (BLE) a montré une efficacité énergétique et une robustesse supérieures à celles d'autres protocoles WSN bien connus, ce qui fait BLE un candidat solide pour la mise en œuvre dans des scénarios IoT. En outre, BLE est présent dans presque tous les smartphones, ce qui en fait une télécommande universelle omniprésente pour les maisons intelligentes, les bâtiments ou les villes. Néanmoins, l'amélioration de la performance BLE pour les cas typiques d'utilisation de l'IoT, où la durée de vie de la batterie de nombreuses années, est toujours nécessaire.Dans ce travail, nous avons évalué les performances de BLE en termes de latence et de consommation d'énergie sur la base de modèles analytiques afin d'optimiser ses performances et d'obtenir son niveau maximal d'efficacité énergétique sans modification de la spécification en premier lieu. À cette fin, nous avons proposé une classification des scénarios ainsi que des modes de fonctionnement pour chaque scénario. L'efficacité énergétique est atteinte pour chaque mode de fonctionnement en optimisant les paramètres qui sont affectés aux nœuds BLE pendant la phase de découverte du voisin. Cette optimisation des paramètres a été réalisée à partir d'un modèle énergétique extrait de l'état de la technique. Le modèle, à son tour, a été optimisé pour obtenir une latence et une consommation d'énergie quel que soit le comportement des nœuds à différents niveaux: application et communication. Puisqu'un nœud peut être le périphérique central à un niveau, alors qu'il peut être le périphérique à l'autre niveau en même temps, ce qui affecte la performance finale des nœuds.En outre, un nouveau modèle d'estimation de la durée de vie de la batterie a été présenté pour montrer l'impact réel de l'optimisation de la consommation énergétique sur la durée de vie des nœuds, de façon rapide (en termes de temps de simulation) et réaliste (en tenant compte des données empiriques). Les résultats de performance ont été obtenus dans notre simulateur Matlab basé sur le paradigme OOP, à travers l'utilisation de plusieurs cas de test IoT. En outre, le modèle de latence utilisé pour notre étude a été validé expérimentalement ainsi que l'optimisation des paramètres proposée, montrant une grande précision.Après avoir obtenu les meilleures performances possibles de BLE sans modification de la spécification, nous avons évalué les performances du protocole en implémentant le concept de Wake-Up radio (WuR), qui est un récepteur d’ultra-faible consommation et qui est en charge de détecter le canal de communication, en attente d'un signal adressé au nœud, puis réveiller la radio principale. Ainsi, la radio principale, qui consomme beaucoup plus d'énergie, peut rester en mode veille pendant de longues périodes et passer en mode actif uniquement pour la réception de paquets, économisant ainsi une quantité d'énergie considérable. Nous avons démontré que la durée de vie de BLE peut être significativement augmentée en implémentant une WuR et nous proposons une modification du protocole afin de rendre ce protocole compatible avec un mode de fonctionnement qui inclut une WuR. Pour cela, nous avons étudié l'état de l'art de la WuR et évalué la durée de vie des périphériques BLE lorsqu'une WuR sélectionnée est implémentée du côté masterThe Internet of Things (IoT) is announced as the next big technological revolution where billions of devices will interconnect using Internet technologies and let users interact with the physical world, allowing Smart Home, Smart Cities, smart everything. Wireless Sensor Network (WSN) are crucial for turning the vision of IoT into a reality, but for this to come true, many of these devices need to be autonomous in energy. Hence, one major challenge is to provide multi-year lifetime while powered on batteries or using harvested energy. Bluetooth Low Energy (BLE) has shown higher energy efficiency and robustness than other well known WSN protocols, making it a strong candidate for implementation in IoT scenarios. Additionally, BLE is present in almost every smartphone, turning it into perfect ubiquitous remote control for smart homes, buildings or cities. Nevertheless, BLE performance improvement for typical IoT use cases, where battery lifetime should reach many years, is still necessary.In this work we evaluated BLE performance in terms of latency and energy consumption based on analytical models in order to optimize its performance and obtain its maximum level of energy efficiency without modification of the specification in a first place. For this purpose, we proposed a scenarios classification as well as modes of operation for each scenario. Energy efficiency is achieved for each mode of operation by optimizing the parameters that are assigned to the BLE nodes during the neighbor discovery phase. This optimization of the parameters was made based on an energy model extracted from the state of the art. The model, in turn, has been optimized to obtain latency and energy consumption regardless of the behavior of the nodes at different levels: application and communication. Since a node can be the central device at one level, while it can be the peripheral device at the other level at the same time, which affects the final performance of the nodes.In addition, a novel battery lifetime estimation model was presented to show the actual impact that energy consumption optimization have on nodes lifetime in a fast (in terms of simulation time) and realistic way (by taking into account empirical data). Performance results were obtained in our Matlab based simulator based on OOP paradigm, through the use of several IoT test cases. In addition, the latency model used for our investigation was experimentally validated as well as the proposed parameter optimization, showing a high accuracy.After obtaining the best performance possible of BLE without modification of the specification, we evaluated the protocol performance when implementing the concept of Wake-Up radio, which is an ultra low power receiver in charge on sensing the communication channel, waiting for a signal addressed to the node and then wake the main radio up. Thus, the main radio which consumes higher energy, can remain in sleep mode for long periods of time and switch to an active mode only for packet reception, therefore saving considerable amount of energy. We demonstrated that BLE lifetime can be significantly increased by implementing a Wake-Up radio and we propose a modification of the protocol in order to render this protocol compatible with an operating mode which includes a Wake-Up radio. For this, we studied the Wake-Up radio state of the art and evaluated BLE devices lifetime when a selected Wake-Up radio is implemented at the master side
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Vu, K. (Kien). "Integrated access-backhaul for 5G wireless networks." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526222431.
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Abstract With the unprecedented growth in mobile data traffic and network densification, the emerging fifth-generation (5G) wireless network warrants a paradigm shift with respect to system design and technological enablers. In this regard, the prime motivation of this thesis is to propose an integrated access-backhaul (IAB) framework to dynamically schedule users, while efficiently providing a wireless backhaul to dense small cells and mitigating interference. In addition, joint resource allocation and interference mitigation solutions are proposed for two-hop and multi-hop self-backhauled millimeter wave (mmWave) networks. The first contribution of this thesis focuses on a multi-user two-hop relay cellular system in which a massive antenna array enabled macro base station (BS) simultaneously provides high beamforming gains to outdoor users, and wireless backhauling to outdoor small cells. Moreover, a hierarchical interference mitigation scheme is applied to efficiently mitigate cross-tier and co-tier interference. In the second contribution, a multi-hop self-backhauled mmWave communication scenario is studied whereby a joint multi-hop multi-path selection and rate allocation framework is proposed to enable Gbps data rates with reliable communications. Using reinforcement learning techniques, a dynamic and efficient re-routing solution is proposed to cope with blockage and latency constraints. Finally, a risk-sensitive learning solution is leveraged to provide high-reliability and low-latency communications. In summary, the dissertation analyses key trade-offs between (i) capacity and latency, (ii) reliability and network density. Extensive simulation results were carried out to verify the performance gains of the proposed algorithms compared to several baselines and for different network settings. Key findings show significant improvements in terms of higher data rates, lower latency, and reliable communications with some trade-offsTiivistelmä Liikkuvan dataliikenteen ennennäkemättömän kasvun ja verkkojen tihentymisen seurauksena pian käyttöön tulevien viidennen sukupolven (5G) langattomien verkkojen järjestelmäsuunnittelua ja teknologisten mahdollistajien käyttöä on täytynyt lähestyä kokonaan uudesta näkökulmasta. Niinpä tämän väitöstyön johtavana ajatuksena on ehdottaa integroitua verkkoon pääsyn ja runkoverkkoyhteyden muodostamismallia, jossa käyttäjät resursoidaan dynaamisesti ja samalla muodostetaan tehokkaat runkoverkkoyhteydet piensoluille. Tätä varten tutkitaan resurssiallokaation ja häiriöiden lieventämisen yhteisratkaisuja, jotka tukevat kahden tai useamman hypyn yhteyksiä ja samanaikaista runkoverkkoyhteyden luomista millimetriaaltoalueen verkoissa. Työn alkuosa keskittyy usean käyttäjän välitinavusteiseen kahden hypyn solukkoverkkoon, jossa makrotukiasemassa käytetään suurta antenniryhmää muodostamaan samanaikaisesti suuren vahvistuksen antennikeiloja käyttäjälinkeille ja langattomalle runkoyhteysosuudelle. Lisäksi sovelletaan hierarkkista häiriönvaimennusmenetelmää saman kerroksen ja kerrosten välisen häiriön tehokkaaseen vähentämiseen. Työn seuraavassa osassa arvioidaan usean hypyn runkoverkkoyhteyden muodostuksen tutkimusongelmaa millimetrialueen kommunikaatiossa kehittämällä yhdistetty menetelmä usean hypyn monipolkuvalinnalle ja tiedonsiirtoresurssien allokoinnille. Tällä tähdätään gigabittiluokan datanopeuksiin ja luotettavaan tietoliikenteeseen millimetrialueella. Vahvistavan oppimisen tekniikan avulla esitellään dynaaminen ja tehokas uudelleenreitityskonsepti toimimaan esto- ja viiverajoitusten kanssa. Lopuksi hyödynnetään riskisensitiivistä oppimista ja antennidiversiteettitekniikoita suuren luotettavuuden ja pienen latenssin saavuttamiseksi millimetrialueen tiedonsiirrossa. Näiden avulla analysoidaan kaupankäyntiä esimerkiksi (i) kapasiteetin ja latenssin sekä (ii) luotettavuuden ja verkon tiheyden/kuormituksen välillä. Mittavien suoritettujen simulointien avulla osoitetaan ehdotettujen algoritmien suorituskykyedut suhteessa tunnettuihin verrokkeihin useissa eri skenaarioissa. Tulosten perusteella saavutetaan merkittäviä kustannussäästöjä infrastruktuurin ja runkoverkon osalta sekä päästään suuriin datanopeuksiin ja parannuksiin pienen latenssin luotettavassa tietoliikenteessä
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Bertolini, Simone. "Progettazione e sviluppo di un Flow Meter a basso consumo energetico per impianti di irrigazione intelligenti." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20531/.
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L’acqua non è sempre un bene fruibile in qualsiasi momento da tutti.
Spesso viene sprecata senza ritegno nei momenti in cui vi è abbondanza per poi trovarsi a doverne limitare l’uso nei periodi di siccità.
In particolare, focalizzandoci sullo scenario agricolo, è possibile rilevare consumi di acqua anche al di sopra del 50% superiori al reale fabbisogno del terreno e delle colture.
Questi sprechi possono essere dovuti a diverse motivazioni, come per esempio impianti di irrigazione mal progettati, sistemi di distribuzione e conteggio empirici etc…
L’obiettivo di questo progetto è il voler eliminare tutti gli errori derivati da approssimazioni nel conteggio della quantità di acqua distribuita.
Per permettere questo è stato quindi sviluppato un contatore di flusso, denominato Flow Meter, in grado di garantire una precisione al centinaio di litri nel conteggio.
I punti di forza di questo sistema sono, oltre che la sufficiente precisione di conteggio, la possibilità di trasmettere i dati a lungo raggio grazie all’utilizzo della tecnologia di trasmissione a radiofrequenza LoRa, in combinazione con il bassissimo costo energetico del modulo che lo rende in grado di poter sopravvivere a lungo con un solo pacco batteria.
Questo dispositivo è stato poi inserito all’interno del progetto SWAMP (Smart Water Management Platform), mettendolo in condizione di poter coesistere in un ambiente eterogeneo di sensori, i cui dati vengono resi disponibili in una piattaforma di gestione online.
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Tovinakere, Dwarakanath Vivek. "Contrôleurs reconfigurables ultra-faible consommation pour les réseaux de capteurs sans fil." Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00859921.
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Un nœud d'un réseau de capteurs sans fil traite dans ses unités de calcul les signaux issus de plusieurs types de capteurs et effectue différentes tâches liées aux protocoles de communication. Devant exécuter plusieurs types de contrôle, sa flexibilité est un paramètre très important. Les solutions à base de microcontrôleurs ou de FPGA ont été proposées pour aborder le besoin de flexibilité, mais au prix d'une efficacité énergétique réduite. Dans cette thèse, des contrôleurs flexibles à ultra-faible énergie basés sur un contexte de micro-tâches reconfigurables sont explorés comme alternative. Des architectures modulaires pour des machines d'états finis (FSM) et des chemins de données (DP) reconfigurables sont proposées. Les techniques de coupure de l'alimentation (PG pour power gating) sont utilisées pour adapter la consommation aux besoins et réduire la puissance statique. Dans un premier temps, des modèles pour l'estimation des paramètres clés d'un circuit avec PG sont proposés au niveau porte. Ensuite, les opportunités des techniques PG sont déterminées sur les FSM et DP reconfigurables pour en réduire l'énergie. Dans les chemins de données, la reconfiguration fait varier la précision des opérateurs et le PG permet d'éteindre les blocs logiques inutilisés. Une gestion de l'alimentation au niveau lookup table (LUT) est proposée pour réduire les courants de fuite en mode actif et en veille dans les FSM reconfigurables. Des résultats montrent les très bonnes performances des architectures proposées par rapport aux processeurs et FPGA.
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Kraemer, Michael M. "Design of a low-power 60 GHz transceiver front-end and behavioral modeling and implementation of its key building blocks in 65 nm CMOS." Thesis, Toulouse, INSA, 2010. http://www.theses.fr/2010ISAT0027/document.
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La réglementation mondiale, pour des appareils de courte portée, permet l’utilisation sans licence de plusieurs Gigahertz de bande autour de 60 GHz. La bande des 60 GHz répond aux besoins des applications telles que les réseaux de capteurs très haut débit autonome en énergie,ou les transmissions à plusieurs Gbit/s avec des contraintes de consommation d’énergie. Il y a encore peu de temps, les interfaces radios fonctionnant dans la bande millimétrique n’étaient réalisables qu’en utilisant des technologies III-V couteuses. Aujourd’hui, les avancées des technologies CMOS nanométriques permettent la conception et la production en masse des circuits intégrées radiofréquences (RFIC) à faible coût.Cette thèse s’inscrit dans des travaux de recherches dédiés à la réalisation d’un système dans un boîtier (SiP, System in Package) à 60 GHz contenant à la fois l’interface radio (bande de base et circuits RF) ainsi qu’un réseau d’antennes. La première partie de cette thèse est dédiée la conception de la tête RF de l’émetteur-récepteur à faible consommation pour l’interface radio. Les blocs clefs de cette tête RF (amplificateurs, mélangeurs et un oscillateur commandé en tension) sont conçus, réalisés et mesurés en utilisant la technologie CMOS 65 nm de ST Microelectronics. Des éléments actifs et passifs sont développés spécifiquement pour l’utilisation au sein de ces blocs. Une étape importante vers l’intégration de la tête RF complète de l’émetteur-récepteur est l’assemblage de ces blocs de base afin de réaliser une puce émetteur et une puce récepteur. A ce but, une tête RF pour le récepteur a été réalisée. Ce circuit présent une consommation et un encombrement plus réduit que l’état de l’art.La deuxième partie de cette thèse présente le développement des modèles comportementaux des blocs de base conçus. Ces modèles au niveau système sont nécessaires afin de simuler le comportement du SIP, qui devient trop complexe si des modèles détaillés du niveau circuitsont utilisés. Dans cette thèse, une nouvelle technique modélisant le comportement en régime transitoire et régime permanent ainsi que le bruit de phase des oscillateurs commandés en tension est proposée. Ce modèle est implémenté dans le langage de description de matérielVHDL-AMS. La technique proposée utilise des réseaux de neurones artificiels pour approximer la caractéristique non linéaire du circuit. La dynamique est décrite dans l’espace d’état. Grâce à ce modèle, il est possible de réduire d’une façon drastique le temps de calcul des simulations système tout en conservant une excellente précisionWorldwide regulations for short range communication devices allow the unlicensed use of several Gigahertz of bandwidth in the frequency band around 60GHz. This 60GHz band is ideally suited for applications like very high data rate, energy-autonomous wireless sensor networks or Gbit/s multimedia links with low power constraints. Not long ago, radio interfaces that operate in the millimeter-wave frequency range could only be realized using expensive compound semiconductor technologies. Today, the latest sub-micron CMOS technologies can be used to design 60GHz radio frequency integrated circuits (RFICs)at very low cost in mass production. This thesis is part of an effort to realize a low power System in Package (SiP) including both the radio interface (with baseband and RF circuitry) and an antenna array to directly transmit and receive a 60GHz signal. The first part of this thesis deals with the design of the low power RF transceiver front-end for the radio interface. The key building blocks of this RF front-end (amplifiers, mixers and a voltage controlled oscillator (VCO)) are designed, realized and measured using the 65nm CMOS technology of ST Microelectronics. Full custom active and passive devices are developed for the use within these building blocks. An important step towards the full integration of the RF transceiver front-end is the assembly of these building blocks to form basic transmitter and receiver chips. Circuits with small chip size and low power consumption compared to the state of the art have been accomplished.The second part of this thesis concerns the development of behavioral models for the designed building blocks. These system level models are necessary to simulate the behavior of the entire SiP, which becomes too complex when using detailed circuit level models. In particular, a novel technique to model the transient, steady state and phase noise behavior of the VCO in the hardware description language VHDL-AMS is proposed and implemented. The model uses a state space description to describe the dynamic behavior of the VCO. Its nonlinearity is approximated by artificial neural networks. A drastic reduction of simulation time with respect to the circuit level model has been achieved, while at the same time maintaining a very high level of accuracy
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Ma, Hang. "Using chaos to enhance multi-user time-of-arrival estimation : application to UWB ranging systems." Thesis, Toulouse, INSA, 2014. http://www.theses.fr/2014ISAT0008/document.
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Dans les décennies à venir, la connaissance d’informations très précises concernant la position d’un objet permettra de créer des applications révolutionnaires dans les domaines sociaux, médicaux, commerciaux et militaires. La technologie Ultra-Wideband (UWB) est considérée comme un bon candidat permettant de fournir des capacités de localisation précise grâce à la mesure de l’estimation du temps d'arrivée (TOA). Dans cette thèse, des algorithmes de mesure de distance dans le cas multi-utilisateurs pour des systèmes UWB sont étudiés afin d'atteindre une bonne précision pour une faible complexité, avec de la robustesse aux interférences multi-utilisateur et dans le cas d’un grand nombre d'utilisateurs. Au cours de la dernière décennie, les signaux chaotiques ont reçu une attention significative en raison d'un certain nombre de caractéristiques intéressantes. Les signaux chaotiques sont des signaux non périodiques, déterministes ou considérés comme pseudo-aléatoires provenant de systèmes dynamiques non linéaires. Leur bonne autocorrélation et leurs faibles propriétés d’inter corrélation les rendent particulièrement résistants aux évanouissements par trajets multiples et capables d'atténuer les interférences multi-utilisateur (MUI). En raison de leur grande sensibilité aux conditions initiales, il est possible de générer un grand nombre de signaux chaotiques pour accroître la capacité globale du système. Dans cette thèse, deux nouveaux algorithmes d'estimation de TOA sont proposés dans un cadre multi-utilisateur avec une faible complexité et une bonne robustesse. Le nombre d'utilisateurs pris en charge par ces deux algorithmes est beaucoup plus grand que dans le cas des estimateurs de TOA actuels. Cependant, l'utilisation de séquences d'étalement classique et d’impulsion limite l'amélioration des performances et la capacité du système. Afin d’apporter des améliorations, des signaux chaotiques sélectionnés sont utilisés comme séquences d'étalement ou impulsion dans les algorithmes proposés. Grâce à l'utilisation de signaux chaotiques, notre algorithme est non seulement amélioré, mais permet également l’utilisation d’un plus grand nombre d'utilisateurs par comparaison avec l’algorithme utilisant des signaux classiquesIn the coming decades, highly accurate position information has the potential to create revolutionary applications in the social, medical, commercial and military areas. Ultra-Wideband (UWB) technology is considered as a potential candidate for enabling accurate localization capabilities through Time-of-Arrival (TOA) based ranging techniques. Over the past decade, chaotic signals have received significant attention due to a number of attractive features. Chaotic signals are aperiodic, deterministic, and random-like signals derived from nonlinear dynamical systems whose good autocorrelation, low cross-correlation and sensitivity to the initial conditions make them particularly suitable to ranging systems. In this thesis, two new multiuser TOA estimation algorithms are proposed with low complexity and robustness to MUI, the number of users supported by which is much larger than current multiuser TOA estimators. While, the use of classic spreading sequences and ranging pulse constrain the further improvement of ranging performance and system capacity. For breaking through the limit brought by the classic signals, the selected chaotic signals are employed as the spreading sequences or ranging pulse in our proposed algorithms. With the use of chaotic signals, our proposed algorithm not only obtains the additional improvement, but also with capability to support larger number of users comparing with its counterpart using classic signals
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Inanlou, Farzad Michael-David. "Innovative transceiver approaches for low-power near-field and far-field applications." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52245.
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Wireless operation, near-field or far-field, is a core functionality of any mobile or autonomous system. These systems are battery operated or most often utilize energy scavenging as a means of power generation. Limited access to power, expected long and uninterrupted operation, and constrained physical parameters (e.g. weight and size), which limit overall power harvesting capabilities, are factors that outline the importance for innovative low-power approaches and designs in advanced low-power wireless applications. Low-power approaches become especially important for the wireless transceiver, the block in charge of wireless/remote functionality of the system, as this block is usually the most power hungry component in an integrated system-on-chip (SoC). Three such advanced applications with stringent power requirements are examined including space-based exploratory remote sensing probes and their associated radiation effects, millimeter-wave phased-array radar for high-altitude tactical and geological imaging, and implantable biomedical devices (IMDs), leading to the proposal and implementation of low-power wireless solutions for these applications in SiGe BiCMOS and CMOS and platforms.
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Fray, Mickaël. "Etude d'antennes large bande miniatures à spirale d'Archimède." Thesis, Brest, 2019. http://www.theses.fr/2019BRES0043.
Full textAbstract:
L’objectif de la thèse est d’étudier une antenne miniature large bande de fréquence, selon un cahier des charges défini par l’entreprise Thales. Cette antenne doit donc avoir une bande de fréquence supérieure à la décade i.e. un rapport 10 entre fréquence haute et basse de fonctionnement. Un état de l’art des antennes large bande nous permet d’orienter le choix de l’élément rayonnant de l’antenne vers la spirale d’Archimède. Après un état de l’art des techniques pour élargir la bande de fréquence basse, nos recherches se sont orientées vers l’étude de l’apport d’un substrat diélectrique sur les performances radioélectriques de l’antenne spirale. Une étude approfondie de cette dernière associée à différentes configurations de substrats diélectriques nous permet de constater un élargissement de la bande de fréquence basse de fonctionnement en lien avec la permittivité effective du milieu. Néanmoins, des dégradations sur les performances radioélectriques proportionnelles à la permittivité effective sont également constatées. Avec la mise en place de critères permettant de quantifier les apports positifs et négatifs d’un substrat diélectrique, une modification géométrique consistant à diminuer le ratio de métallisation de la spirale est étudiée. Elle a pour but de réduire les dégradations dans la bande de fréquence haute en gardant un élargissement de la bande de fréquence basse conséquentThe goal of the present thesis is to study a wideband miniaturized antenna compatible with specifications set by Thales enterprise. Thus, this antenna needs to achieve a frequency band superior to a decade i.e. a ratio of 10 between high and low operation frequency. A state of the art of wideband antennas has leaded us to choose an Archimedean spiral as our main radiating element. After performing a state of the art of low band broadening techniques, our researches leaded us on the study of the contribution of a dielectric substrate on the electrical performances of spirals. A deepen study of the spiral associated with different configurations of dielectric substrates has permitted us to notice a low band broadening of operation linked to the effective permittivity of the environment. However, some degradation of electrical performances proportional to the effective permittivity can be noted. Along with the incorporation of criteria allowing us to quantify the positive and negative contributions of a dielectric substrate, a geometrical modification consisting of lowering the metal ratio of the spiral is studied. The goal is to reduce degradation in the upper frequency band while maintaining a satisfying low band broadening
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Yaacoub, Tina. "Nouvelles approches pour l'estimation du canal ultra-large bande basées sur des techniques d'acquisition compressée appliquées aux signaux à taux d'innovation fini IR-UWB." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0077/document.
Full textAbstract:
La radio impulsionnelle UWB (IR-UWB) est une technologie de communication relativement récente, qui apporte une solution intéressante au problème de l’encombrement du spectre RF, et qui répond aux exigences de haut débit et localisation précise d’un nombre croissant d’applications, telles que les communications indoor, les réseaux de capteurs personnels et corporels, l’IoT, etc. Ses caractéristiques uniques sont obtenues par la transmission d’impulsions de très courte durée (inférieure à 1 ns), occupant une largeur de bande allant jusqu’à 7,5 GHz, et ayant une densité spectrale de puissance extrêmement faible (inférieure à -43 dBm/MHz). Les meilleures performances d’un système IR-UWB sont obtenues avec des récepteurs cohérents de type Rake, au prix d’une complexité accrue, due notamment à l’étape d’estimation du canal UWB, caractérisé par de nombreux trajets multiples. Cette étape de traitement nécessite l’estimation d’un ensemble de composantes spectrales du signal reçu, sans pouvoir faire appel aux techniques d’échantillonnage usuelles, en raison d’une limite de Nyquist particulièrement élevée (plusieurs GHz).Dans le cadre de cette thèse, nous proposons de nouvelles approches, à faible complexité, pour l’estimation du canal UWB, basées sur la représentation parcimonieuse du signal reçu, la théorie de l’acquisition compressée, et les méthodes de reconstruction des signaux à taux d’innovation fini. La réduction de complexité ainsi obtenue permet de diminuer de manière significative le coût d’implémentation du récepteur IR-UWB et sa consommation. D’abord, deux schémas d’échantillonnage compressé, monovoie (filtre SoS) et multivoie (MCMW) identifiés dans la littérature sont étendus au cas des signaux UWB ayant un spectre de type passe-bande, en tenant compte de leur implémentation réelle dans le circuit. Ces schémas permettent l’acquisition des coefficients spectraux du signal reçu et l’échantillonnage à des fréquences très réduites ne dépendant pas de la bande passante des signaux, mais seulement du nombre des trajets multiples du canal UWB. L’efficacité des approches proposées est démontrée au travers de deux applications : l’estimation du canal UWB pour un récepteur Rake cohérent à faible complexité, et la localisation précise en environnement intérieur dans un contexte d’aide à la dépendance.En outre, afin de réduire la complexité de l’approche multivoie en termes de nombre de voies nécessaires pour l’estimation du canal UWB, nous proposons une architecture à nombre de voies réduit, en augmentant le nombre d’impulsions pilotes émises.Cette même approche permet aussi la réduction de la fréquence d’échantillonnage associée au schéma MCMW. Un autre objectif important de la thèse est constitué par l’optimisation des performances des approches proposées. Ainsi, bien que l’acquisition des coefficients spectraux consécutifs permette une mise en oeuvre simple des schémas multivoie, nous montrons que les coefficients ainsi choisis, ne donnent pas les performances optimales des algorithmes de reconstruction. Ainsi, nous proposons une méthode basée sur la cohérence des matrices de mesure qui permet de trouver l’ensemble optimal des coefficients spectraux, ainsi qu’un ensemble sous-optimal contraint où les positions des coefficients spectraux sont structurées de façon à faciliter la conception du schéma MCMW. Enfin, les approches proposées dans le cadre de cette thèse sont validées expérimentalement à l’aide d’une plateforme expérimentale UWB du laboratoire Lab-STICC CNRS UMR 6285Ultra-wideband impulse radio (IR-UWB) is a relatively new communication technology that provides an interesting solution to the problem of RF spectrum scarcity and meets the high data rate and precise localization requirements of an increasing number of applications, such as indoor communications, personal and body sensor networks, IoT, etc. Its unique characteristics are obtained by transmitting pulses of very short duration (less than 1 ns), occupying a bandwidth up to 7.5 GHz, and having an extremely low power spectral density (less than -43 dBm / MHz). The best performances of an IR-UWB system are obtained with Rake coherent receivers, at the expense of increased complexity, mainly due to the estimation of UWB channel, which is characterized by a large number of multipath components. This processing step requires the estimation of a set of spectral components for the received signal, without being able to adopt usual sampling techniques, because of the extremely high Nyquist limit (several GHz).In this thesis, we propose new low-complexity approaches for the UWB channel estimation, relying on the sparse representation of the received signal, the compressed sampling theory, and the reconstruction of the signals with finite rate of innovation. The complexity reduction thus obtained makes it possible to significantly reduce the IR-UWB receiver cost and consumption. First, two existent compressed sampling schemes, single-channel (SoS) and multi-channel (MCMW), are extended to the case of UWB signals having a bandpass spectrum, by taking into account realistic implementation constraints. These schemes allow the acquisition of the spectral coefficients of the received signal at very low sampling frequencies, which are not related anymore to the signal bandwidth, but only to the number of UWB channel multipath components. The efficiency of the proposed approaches is demonstrated through two applications: UWB channel estimation for low complexity coherent Rake receivers, and precise indoor localization for personal assistance and home care.Furthermore, in order to reduce the complexity of the MCMW approach in terms of the number of channels required for UWB channel estimation, we propose a reduced number of channel architecture by increasing the number of transmitted pilot pulses. The same approach is proven to be also useful for reducing the sampling frequency associated to the MCMW scheme.Another important objective of this thesis is the performance optimization for the proposed approaches. Although the acquisition of consecutive spectral coefficients allows a simple implementation of the MCMW scheme, we demonstrate that it not results in the best performance of the reconstruction algorithms. We then propose to rely on the coherence of the measurement matrix to find the optimal set of spectral coefficients maximizing the signal reconstruction performance, as well as a constrained suboptimal set, where the positions of the spectral coefficients are structured so as to facilitate the design of the MCMW scheme. Finally, the approaches proposed in this thesis are experimentally validated using the UWB equipment of Lab-STICC CNRS UMR 6285
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Adami, Salah-Eddine. "Optimisation de la récupération d'énergie dans les applications de rectenna." Phd thesis, Ecole Centrale de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00967525.
Full textAbstract:
Les progrès réalisés durant ces dernières années dans le domaine de la microélectronique et notamment vis-à-vis de l'augmentation exponentielle de la densité d'intégration des composants et des systèmes a participé activement à l'apparition et au développement de systèmes portables communicants de plus en plus performants et polyvalents. La R&D dans les technologies de stockage d'énergie n'a pas suivi cette tendance d'évolution très rapide ; ce qui constitue un handicap majeur dans les évolutions futures des systèmes portables. La transmission d'énergie sans fils sur des distances considérables (plusieurs dizaines de mètres) grâce aux microondes constitue une solution très prometteuse pour pallier aux problèmes d'autonomie dans le cas des systèmes sans fils communicants. De plus, du fait de l'omniprésence des ondes électromagnétiques dans notre environnement avec des niveaux plus ou moins importants, la récupération et l'exploitation de cette énergie libre est également possible. La rectenna (Rectifying Antenna) est le dispositif permettant de capter et de convertir une onde électromagnétique en une tension continue. Plusieurs travaux de thèse axés sur l'étude et l'optimisation de la rectenna ont été réalisés au sein du laboratoire. Ces travaux avaient montré que pour des faibles niveaux de champs les tensions délivrées par la rectenna sont généralement très faibles et inexploitables. Aussi, comme la majorité des micro-sources d'énergie et à cause de son impédance interne, les performances de la rectenna dépendent fortement de sa charge de sortie. Ainsi, le développement d'un système d'interfaçage de la rectenna est nécessaire afin de pallier ces manquements inhérents du convertisseur RF/DC. Ce genre de système d'interfaçage est généralement absent dans la littérature à cause des faibles niveaux de puissance exploités. Par conséquent, la rectenna est très souvent utilisée tel quelle ; ce qui limite fortement le champ applicatif. Dans ce projet de recherche, un système de gestion énergétique de la rectenna complètement autonome a été conçu, développé et optimisé afin de garantir les performances optimales de la rectenna quelques soient les fluctuations de la puissance d'entrée et celles de la charge de sortie. Le circuit d'interfaçage permet également de fournir à la charge des niveaux de tension utilisables. Le système réalisé est basé tout d'abord sur l'utilisation d'un convertisseur DC/DC résonant pouvant fonctionner d'une manière complètement autonome à partir de niveaux très bas de la tension et de la puissance de la source. Ce convertisseur permet donc de garantir l'autonomie du système en éliminant la nécessité d'une source d'énergie auxiliaire. A cause de ses faibles performances énergétiques, ce convertisseur ne sera utilisé que durant la phase de démarrage. L'efficacité du système en termes de rendement énergétique et d'adaptation d'impédance est garantie grâce à l'utilisation d'un convertisseur Flyback fonctionnant dans son régime de conduction discontinu. Ainsi, une adaptation d'impédance très efficace est réalisée entre la rectenna et la charge de sortie. Ce convertisseur principal fonctionnera durant le régime permanent. Les deux convertisseurs ont été optimisés pour des niveaux de tension et de puissance aussi bas que quelques centaines de mV et quelques μW respectivement. Des mesures expérimentales réalisées sur plusieurs prototypes ont démontré le bon fonctionnement et les excellentes performances prédites par la procédure de conception ; ce qui nous permet de valider notre approche. De plus, les performances obtenues se distinguent parfaitement vis-à-vis de l'état de l'art. Enfin, en fonction de l'application désirée, plusieurs synoptiques d'association des deux structures sont proposés. Ceci inclut également la gestion énergétique de la charge de sortie.
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Alhaddad, Abdolrauf Gawad. "Balanced antennas for mobile handset applications : simulation and measurement of balanced antennas for mobile handsets, investigating specific absorption rate when operated near the human body, and a coplanar waveguide alternative to the balanced feed." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5512.
Full textAbstract:
The main objectives of this research are to investigate and design low profile antennas for mobile handsets applications using the balanced concept. These antennas are considered to cover a wide range of wireless standards such as: DCS (1710-1880 MHz), PCS (1850-1990 MHz), UMTS (1920-2170 MHz), WLAN (2400-2500 MHz and 5000-5800 MHz) and UWB frequency bands. Various antennas are implemented based on built-in planar dipole with a folded arm structure. The performance of several designed antennas in terms of input return loss, radiation patterns, radiation efficiency and power gain are presented and several remarkable results are obtained. The measurements confirm the theoretical design concept and show reasonable agreement with computations. The stability performance of the proposed antenna is also evaluated by analysing the current distribution on the mobile phone ground plane. The specific absorption rate (SAR) performance of the antenna is also studied experimentally by measuring antenna near field exposure. The measurement results are correlated with the calculated ones. A new dual-band balanced antenna using coplanar waveguide structure is also proposed, discussed and tested; this is intended to eliminate the balanced feed network. The predicted and measured results show good agreement, confirming good impedance bandwidth characteristics and excellent dual-band performance. In addition, a hybrid method to model the human body interaction with a dual band balanced antenna structure covering the 2.4 GHz and 5.2 GHz bands is presented. Results for several test cases of antenna locations on the body are presented and discussed. The near and far fields were incorporated to provide a full understanding of the impact on human tissue. The cumulative distribution function of the radiation efficiency and absorbed power are also evaluated.
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Alhaddad, A. G. "Balanced antennas for mobile handset applications. Simulation and Measurement of Balanced Antennas for Mobile Handsets, investigating Specific Absorption Rate when operated near the human body, and a Coplanar Waveguide alternative to the Balanced Feed." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5512.
Full textAbstract:
The main objectives of this research are to investigate and design low profile antennas
for mobile handsets applications using the balanced concept. These antennas are
considered to cover a wide range of wireless standards such as: DCS (1710¿1880 MHz),
PCS (1850¿1990 MHz), UMTS (1920¿2170 MHz), WLAN (2400¿2500 MHz and 5000
¿ 5800 MHz) and UWB frequency bands. Various antennas are implemented based on
built-in planar dipole with a folded arm structure.
The performance of several designed antennas in terms of input return loss, radiation
patterns, radiation efficiency and power gain are presented and several remarkable
results are obtained. The measurements confirm the theoretical design concept and show
reasonable agreement with computations. The stability performance of the proposed
antenna is also evaluated by analysing the current distribution on the mobile phone
ground plane. The specific absorption rate (SAR) performance of the antenna is also
studied experimentally by measuring antenna near field exposure. The measurement
results are correlated with the calculated ones.
A new dual-band balanced antenna using coplanar waveguide structure is also proposed,
discussed and tested; this is intended to eliminate the balanced feed network. The
predicted and measured results show good agreement, confirming good impedance
bandwidth characteristics and excellent dual-band performance.
In addition, a hybrid method to model the human body interaction with a dual band
balanced antenna structure covering the 2.4 GHz and 5.2 GHz bands is presented.
Results for several test cases of antenna locations on the body are presented and
discussed. The near and far fields were incorporated to provide a full understanding of
the impact on human tissue. The cumulative distribution function of the radiation
efficiency and absorbed power are also evaluated.UK Engineering and Physical Sciences Research Council (EPSRC)
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Tall, Ndiogou. "Etude et réalisation de circuits de récupération d'horloge et de données analogiques et numériques pour des applications bas débit et très faible consommation." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4717.
Full textAbstract:
Les circuits de récupération d'horloge et de données sont nécessaires au bon fonctionnement de plusieurs systèmes de communication sans fil. Les travaux effectués dans le cadre de cette thèse concernent le développement de ces circuits avec d'une part la réalisation, en technologie HCMOS9 0,13 μm de STMICROELECTRONICS, de circuits CDR analogiques à 1 et 54 Mbit/s, et d'autre part, la mise en œuvre de fonctions CDR numériques programmables à bas débit. Un circuit CDR fonctionnant à plus bas débit (1 Mbit/s) a été conçu dans le cadre de la gestion d'énergie d'un récepteur ULB impulsionnel non cohérent. Ces deux structures ont été réalisées à l'aide de PLL analogiques du 3ème ordre. Un comparateur de phase adapté aux impulsions issues du détecteur d'énergie a été proposé dans cette étude. Les circuits ont ensuite été dimensionnés dans le but d'obtenir de très bonnes performances en termes de jitter et de consommation. En particulier, les performances mesurées (sous pointes) du circuit CDR à 1 Mbit/s permettent d'envisager une gestion d'énergie efficace (réduction de plus de 97% de la consommation du récepteur). Dans le cadre d'une chaîne de télémesure avion vers sol, deux circuits CDR numériques ont également été réalisés durant cette thèse. Une PLL numérique du second degré a été implémentée en vue de fournir des données et une horloge synchrone de celles-ci afin de piloter une chaîne SOQPSK entièrement numérique. Un circuit ELGS a également mis au point pour fonctionner au sein d'un récepteur PCM/FMClock and data recovery circuits are required in many wireless communication systems. This thesis is about development of such circuits with: firstly, the realization, in HCMOS9 0.13 μm of STMICROELECTRONICS technology, of 1 and 54 Mb/s analog CDR circuits, and secondly, the implementation of programmable digital circuits at low rates. In the aim of an impulse UWB transceiver dealing with video transmission, a CDR circuit at 54 Mb/s rate has been realized to provide clock signal synchronously with narrow pulses (their duration is about a few nanoseconds) from the energy detector. Another CDR circuit has been built at 1 Mb/s rate in a non-coherent IR- UWB receiver power management context. Both circuits have been implemented as 3rd order analog PLL. In this work, a phase comparator suitable for “RZ low duty cycle” data from the energy detector has been proposed. Circuits have been sized to obtain very good performances in terms of jitter and power consumption. Particularly, measured performances of the 1 Mb/s CDR circuit allow to plan an efficient power management (a decrease of more than 97% of the receiver total power consumption). In the context of a telemetry system from aircraft to ground, two digital CDR circuits have also been implemented. A second order digital PLL has been adopted in order to provide synchronous clock and data to an SOQPSK digital transmitter. Also, a digital ELGS circuit has been proposed to work in a PCM/FM receiver. For both CDR structures, the input signal rate is programmable and varies globally from 1 to 30 Mb/s
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Diao, Pape Sanoussy. "Système de détection embarqué ULB millimétrique pour la perception de l'environnement." Thesis, Paris Est, 2019. http://www.theses.fr/2019PESC2005/document.
Full textAbstract:
Avec le contexte actuel des défis sécuritaires, la détection de petits objets devient un enjeu majeur pour lutter contre les actes malveillants. Mais les évolutions des technologies en bandes millimétriques et le potentiel de ces bandes, notamment autour de 60 GHz peuvent faciliter la conception de systèmes de plus en plus performants, permettant de répondre à ces enjeux. Cette thèse s’inscrit dans ce contexte pour proposer un système de détection ultra-large bande (ULB) millimétrique pour des applications de courte portée. Après un état de l'art détaillé des fondamentaux de la détection, nous présentons une validation de l'estimation de la surface équivalente radar (SER) par simulation avec le logiciel HFSS et par mesures en chambre anéchoïque. Ces deux études nous ont permis d'identifier les éléments essentiels à l'analyse système et les paramètres critiques de la détection d'objets canoniques cylindres et plaques. Une fois l'analyse système cernée, nous avons proposé une approche de détection multi-bande basée sur le radar monostatique pour améliorer la couverture de détection des systèmes, mais aussi et surtout pour pallier la limitation de la détection des objets en fonction de leur orientation par rapport à l'axe de viser de l'antenne. Nous avons également proposé une architecture (émetteur-récepteur) simple pouvant être associée au principe de détection. Le dimensionnement du système nous a permis d'identifier les amplificateurs faible bruit (LNAs) comme éléments critiques du récepteur et ainsi d'établir leurs spécifications pour atteindre les performances visées. Une comparaison des technologies SG13S de IHP et D007IH de OMMIC est menée dans la dernière partie de ce travail. Le choix de la technologie est justifié et la conception des LNAs sous ADS Keysight est détaillée. Une simulation de l'ensemble du système basée sur les performances des LNAs conçus et sur les simulations de SER est présentée pour illustrer la mise en œuvre de la détection. Enfin, les performances de la détection sont évaluées pour des cibles cylindriques et les apports du système proposé sont illustrés en comparaison avec une détection classique mono-bandeWith the current context of security challenges, small objects detection is becoming a major issue in the fight against malicious acts. However, developments in millimeter-band technologies and the potential of these bands, particularly around 60 GHz, can facilitate the design of increasingly efficient systems to meet these challenges. This thesis is part of this context to propose an ultra-wideband (UWB) millimeter-wave detection system for short-range applications.After a detailed state-of-the-art of the fundamentals of detection, we present a validation of the radar cross-section (RCS) estimation by simulations with HFSS software and by measurements in anechoic chamber. These two studies allowed us to identify the essential elements for system analysis and the critical parameters for the detection of canonical objects such as cylinders and plates.Once the system analysis was identified, we proposed a multi-band detection approach based on monostatic radar to improve the detection coverage of the systems, but also and especially to overcome the limitation of objects detection according to their orientation in relation to the antenna boresight. We also proposed a simple architecture (transceiver) that could be associated with the detection principle. The system design allowed us to identify low noise amplifiers (LNAs) as critical elements of the receiver and thus establish their specifications to achieve the targeted performances.A comparison of IHP's SG13S and OMMIC's D007IH technologies is conducted in the last part of this work. The choice of technology is justified and the design of LNAs under ADS Keysight is detailed. A simulation of the entire system based on the performance of the designed LNAs and RCS simulations is presented to illustrate the implementation of detection. Finally, detection performances are evaluated for cylindrical targets and the contributions of the proposed system are illustrated in comparison with conventional single-band detection
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Hou, Ching-I., and 侯清逸. "Physical-Layer Transceiver Implementation and SDR Platform Verification for 5G Ultra-Reliable Low-Latency Communications." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6wew6r.
Full textAbstract:
碩士元智大學
電機工程學系乙組
107
This thesis is to research the transceiver design of the uplink control and data channels of 5G mobile communication systems. This research focuses on the use of low complexity technology to achieve high reliability and low latency communication proposes. In this thesis, we adopt the 5G-NR physical layer specification, i.e., 3GPP 38.211, to design the transceiver of the Physical Uplink Control Channel (PUCCH) and Physical Uplink Share Channel (PUSCH). In wireless communications, the receiver involves multiple distortion factors, e.g., multipath and carrier frequency offset (CFO) effect. This thesis proposes the low complexity channel estimation/equalization and CFO estimation/compensation to overcome the above factors. Next, to analyze the performance of the proposed algorithms, the software simulation platform of PUCCH and PUSCH channels is built to use for different fading scenarios. Moreover, for SDR software radio verification, the thesis utilizes the E4438C, E4406A instruments, USRP module, and 89600 VSA to evaluate the performances of PUCCH and PUSCH transceivers. Finally, for FPGA board verification, the circuits of the 5G-NR PUSCH transceiver are designed by Simulink HDL coder, which can generate Verilog code and convert to bitstream file via Vivado software. Then, using Simulink HDL verifier software to build Xilinx FPGA circuits, the FPGA hardware circuits can perform the same results with the Simulink software circuits. It confirms the proposed hardware design being correct. To sum up, this thesis combines the theory, simulation, instruments, modules, and circuit design verifications to overcome the multipath and CFO effects and to achieve the 5G purposes of low complexity, high reliable, and low latency communications transceiver design.