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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Multi-Variable Phase and Gain Calibration for Multi-Channel Transmit Signals

Ball, Ryan C. 13 June 2023 (has links)
No description available.
52

Truck Connectivity Platform Using Software Defined Radios

Vasan, Srinath January 2019 (has links)
Hardware updates and feature updates of electronic equipment can take a long time for market implementations. Technology tends to become obsolete by the time the update is launched into the market. In the automotive industry, the service entertainment module (SEM) containing the core logic for Amplitude Modulation (AM), Frequency Modulation (FM), and Digital Audio Broadcasting (DAB) radio tuners lack the facility for software-based updates. One of the major challenges for the infotainment/entertainment modules in the automotive industry is to have a single radio module that can support software updates and multistandard radio technologies from different countries. Software Defined Radios (SDR) can be used to deal with this problem as SDR is a platform to prototype or develop new communication protocols as well as add new features or capabilities to the existing protocols without requiring major capital expenditures. SDR is a cost-effective radio platform because it can update radio equipment on the fly and provide additional functionality without requiring hardware modifications. By means of software instead of hardware updates, development loops could be shortened and manufacturing costs are reduced. In this thesis, a thorough comparison of a hardware-based tuner and a software-based tuner is performed in the presence of AM/FM/DAB modulated signals based on the metrics specified in ETSI EN 303 345-1 including sensitivity, adjacent channel suppression, far-off channel suppression, cross-modulation, third-order intermodulation, etc. After performance evaluation and comparison, it can be proven that the SDR based system can perform as well as the hardware tuner used in the SEM unit. / Hårdvaruuppdateringar och funktionsuppdateringar av elektronisk utrustning kan ta lång tid för marknadsimplementeringar. Teknik tenderar att bli föråldrad när uppdateringen lanseras på marknaden. Inom fordonsindustrin saknar servicunderhållningsmodulen (SEM) som innehåller kärnlogiken för Amplitude Modulation (AM), Frequency Modulation (FM) och Digital Audio Broadcasting (DAB) radiostemmare möjligheten för programvarubaserade uppdateringar. En av de största utmaningarna för infotainment/ underhållningsmodulerna i bilindustrin är att ha en enda radiomodul som kan stödja programvaruuppdateringar och multistandardradioteknologier från olika länder. Programvarudefinierade radioapparater (SDR) kan användas för att hantera detta problem eftersom SDR är en plattform för att prototypa eller utveckla nya kommunikationsprotokoll samt lägga till nya funktioner eller kapaciteter till de befintliga protokollen utan att kräva stora investeringar. SDR är en kostnadseffektiv radioplattform eftersom den kan uppdatera radioutrustning i farten och ge ytterligare funktionalitet utan att kräva hårdvaruändringar. Med hjälp av mjukvara istället för hårdvaruuppdateringar kan utvecklingsslingor förkortas och tillverkningskostnaderna reduceras. I denna avhandling utförs en grundlig jämförelse av en hårdvarubaserad tuner och en mjukvarubaserad tuner i närvaro av AM / FM / DABmodulerade signaler baserade på mätvärden som specificeras i ETSI EN 303 345-1 inklusive känslighet, intilliggande kanalsuppression, avlägsna kanalundertryckning, tvärmodulering, tredje ordning intermodulering etc. Efter utvärdering och jämförelse av prestanda kan det bevisas att det SDR-baserade systemet kan fungera liksom hårdvarutunern som används i SEM-enheten.
53

Implementation and performance analysis of software defined radio (SDR) based LTE platform for truck connectivity application

Maqsood, Bilal January 2019 (has links)
In today’s modern era of technology mobile communication is evolving with a higher pace than ever before. New features and applications are added in the existing networks each day. The faster development pace requires a faster way to prototype and test the mobile communication standards/ applications to offer faster delivery to the end user. In traditional practices hardware updates and new features growth take long time to market implementations. Technology tends to be obsolete by the time it is to be launched to the market. The reason being long time required for hardware production. However, in the recent days the trend is changing with the emergence of open source cellular stacks to be used with affordable software defined radio (SDR) hardware platforms. Long term evolution (LTE) open source cellular stacks along with the SDR technology are widely used in research these days. However, the performance and limitations of these SDR based open source cellular stacks needs to be explored. In this project a thorough study is performed to access the performance of an open source SDR based LTE user equipment (UE) software stack. A prototype of Category 4 LTE modem is implemented using the srsLTE application suite. Performance analysis is done by looking into the datarate, SNR and radio frequency (RF) characteristics of the implemented solution for multiple system bandwidth settings. A performance comparison is presented between the high performance SDR platform Universal Software Radio Peripheral x310 and the LimeSDR. The results show that the SDR technology is capable of handling wideband signals like LTE. The choice of SDR hardware platform and open source cellular stack depends on the application. The chosen solution for this project i.e. srsLTE performed well for LTE bandwidths 10 MHz and above in terms of downlink data rate. However, the radio frequency characteristics of selected SDR platforms do not comply fully with the 3GPP standard requirements. / I dagens moderna era av teknik utvecklas mobilkommunikation med en högre takt än någonsin tidigare. Nya funktioner och applikationer läggs till i befintliga nätverk varje dag. Den snabbare utvecklingstakten kräver ett snabbare sätt att prototypa och testa mobil kommunikationsstandarder / applikationer för att erbjuda snabbare leverans till slutanvändaren. I traditionell praxis tar hårdvaruuppdateringar och nya funktioner tillväxt lång tid att implementera marknaden. Teknik tenderar att vara föråldrad när den ska lanseras på marknaden. Anledningen är att det krävs lång tid för hårdvaruproduktion. De senaste dagarna förändras emellertid trenden med uppkomsten av cellulära stackar med öppen källkod som ska användas med programvarudefinierad radio (SDR) till överkomliga programvara. par Långtidsutveckling (LTE) med öppna källor, cellulära staplar tillsammans med SDR-tekniken används i stor utsträckning i forskning idag. Prestandan och begränsningarna för dessa SDR-baserade öppna källkodsstapelar måste dock utforskas. I detta projekt utförs en grundlig studie för att fååtkomst till prestanda för en open source SDR-baserad LTE-användarutrustning (UE) -programvarubunke. En prototyp av kategori 4 LTEmodem implementeras med srsLTE-applikationssviten. Prestandeanalys görs genom att undersöka egenskaperna för datarate, SNR och radiofrekvens (RF) för den implementerade lösningen för flera systembandbreddinställningar. En prestandajämförelse presenteras mellan den högpresterande SDR-plattformen Universal Software Radio Peripheral x310 och LimeSDR. Resultaten visar att SDR-tekniken kan hantera bredbandssignaler som LTE. Valet av SDR-hårdvaruplattform och öppen källkods cellstapel beror påapplikationen. Den valda lösningen för detta projekt, dvs srsLTE, fungerade bra för LTE-bandbredd 10 MHz och högre i termer av nedlänks datahastighet. Radiofrekvensegenskaperna för utvalda SDR-plattformar uppfyller dock inte helt 3GPP-standardkraven.
54

Design of a UAV-based radio receiver for avalanche beacon detection using software defined radio and signal processing

Hedlund, Richard January 2019 (has links)
A fully functional proof of concept radio receiver for detecting avalanche beacons atthe frequency 457 kHz was constructed in the work of this master thesis. The radioreceiver is intended to be mounted on an unmanned aerial vehicle (UAV or drone)and used to aid the mountain rescue teams by reducing the rescue time in findingavalanche victims carrying a transmitting beacon. The main parts of this master thesisinvolved hardware requirement analysis, software development, digital signalprocessing and wireless communications. The radio receiver was customized to receive low power signal levels becausemagnetic antennas are used and the avalanche beacon will operate in the reactive nearfield of the radio receiver. Noise from external sources has a significant impact on theperformance of the radio receiver. This master thesis allows for straightforward further development and refining of theradio receiver due to the flexibility of the used open-source software development kitGNU Radio where the digital signal processing was performed.
55

Générateur de coprocesseur pour le traitement de données en flux (vidéo ou similaire) sur FPGA. / CoProcessor generator for real-time data flow processing FPGA

Goavec-Merou, Gwenhael 26 November 2014 (has links)
L’utilisation de matrice de portes logiques reconfigurables (FPGA) est une des seules solutionspour traiter des flux de plusieurs 100 MÉchantillons/seconde en temps-réel. Toutefois, ce typede composant présente une grande difficulté de mise en oeuvre : au delà d’un type langage spécifique,c’est tout un environnement matériel et une certaine expérience qui sont requis pourobtenir les traitements les plus efficaces. Afin de contourner cette difficulté, de nombreux travauxont été réalisés dans le but de proposer des solutions qui, partant d’un code écrit dans unlangage de haut-niveau, vont produire un code dans un langage dédié aux FPGAs. Nos travaux,suivant l’approche d’assemblage de blocs et en suivant la méthode du skeleton, ont visé à mettreen place un logiciel, nommé CoGen, permettant, à partir de codes déjà développés et validés,de construire des chaînes de traitements en tenant compte des caractéristiques du FPGA cible,du débit entrant et sortant de chaque bloc pour garantir l’obtention d’une solution la plus adaptéepossible aux besoins et contraintes. Les implémentations des blocs de traitements sont soitgénérés automatiquement soit manuellement. Les entrées-sorties de chaque bloc doivent respecterune norme pour être exploitable dans l’outil. Le développeur doit fournir une descriptionconcernant les ressources nécessaires et les limitations du débit de données pouvant être traitées.CoGen fournit à l’utilisateur moins expérimenté une méthode d’assemblage de ces blocsgarantissant le synchronisme et cohérence des flux de données ainsi que la capacité à synthétiserle code sur les ressources matérielles accessibles. Cette méthodologie de travail est appliquéeà des traitements sur des flux vidéos (seuillage, détection de contours et analyse des modespropres d’un diapason) et sur des flux radio-fréquences (interrogation d’un capteur sans-fils parméthode RADAR, réception d’un flux modulé en fréquence, et finalement implémentation deblocs de bases pour déporter le maximum de traitements en numérique). / Using Field Programmable Gate Arrays (FPGA) is one of the very few solution for real time processingdata flows of several hundreds of Msamples/second. However, using such componentsis technically challenging beyond the need to become familiar with a new kind of dedicateddescription language and ways of describing algorithms, understanding the hardware behaviouris mandatory for implementing efficient processing solutions. In order to circumvent these difficulties,past researches have focused on providing solutions which, starting from a description ofan algorithm in a high-abstraction level language, generetes a description appropriate for FPGAconfiguration. Our contribution, following the strategy of block assembly based on the skeletonmethod, aimed at providing a software environment called CoGen for assembling various implementationsof readily available and validated processing blocks. The resulting processing chainis optimized by including FPGA hardware characteristics, and input and output bandwidths ofeach block in order to provide solution fitting best the requirements and constraints. Each processingblock implementation is either generated automatically or manually, but must complywith some constraints in order to be usable by our tool. In addition, each block developer mustprovide a standardized description of the block including required resources and data processingbandwidth limitations. CoGen then provides to the less experienced user the means to assemblethese blocks ensuring synchronism and consistency of data flow as well as the ability to synthesizethe processing chain in the available hardware resources. This working method has beenapplied to video data flow processing (threshold, contour detection and tuning fork eigenmodesanalysis) and on radiofrequency data flow (wireless interrogation of sensors through a RADARsystem, software processing of a frequency modulated stream, software defined radio).
56

Flot de conception système sur puce pour radio logicielle / System-on-chip design flow for Software Defined Radio

Tian, Guangye 28 June 2011 (has links)
La Radio Logicielle (SDR) est une radio dont les transformations de la forme d’onde, modulation, démodulation des signaux d’un système radio sont mises en œuvre par du logiciel plutôt que par du matériel à fonctionnalité spécifique. Avec cette approche, l’adaptation du système à une autre norme de communication, ou même l’évolution vers une technologie plus récente peuvent être réalisés par mise à jour du logiciel sans remplacement du matériel qui serait long et coûteux. L’architecture de communication logicielle (Software Communication Architecture, SCA), est une architecture ouverte largement acceptée pour les projets de SDR. La spécification SCA minimise le coût de portage des applications en fournissant une couche d’abstraction qui rend transparentes les méthodes spécifiques de chaque système. Dans cette thèse, on s’intéresse au développement et à la programmation d’une plateforme SDR conforme à SCA.Les nouvelles plateformes de SDR sont en général implémentées sur des plateformes multiprocesseurs système sur puce (MPSoC) exploitant ses importantes ressources de calculs avec une bonne efficacité énergique. Les possibilités d’un rapide développement, déploiement et vérification des logiciels embarqués parallèles sur ces nouvelles plateformes MPSoC sont autant de points clés pour satisfaire les objectifs de performance tout en respectant les délais de mise à disposition sur le marché et le coût de développement.On a proposé un flot de conception pour la SDR avec l’exploration architecturale systématique et l’optimisation multi-objective utilisant le modèle de programmation hybride (distribué client/serveur + parallèle).On a étudié aussi la synthèse de topologie de réseau-sur-puce (PSTRP) qui est une partie du flot de conception. Le problème de la synthèse de la topologie du réseau-sur-puce peut se modéliser sous forme de programme linéaire en nombres entiers. Les résultats montrent que les contraintes d’implémentation, comme la hiérarchie du réseau sur puce, doivent être prises en compte pour obtenir un résultat à la fois mathématiquement optimisé et électroniquement réalisable. / The Software Defined Radio (SDR) is a reconfigurable radio whose functionality is controlled by software, which greatly enhances the reusability and flexibility of waveform applications. The system update is also made easily achievable through software update instead of hardware replacement. The Software Communication Architecture (SCA), on the other hand, is an open architecture framework which specifies an Operating Environment (OE) in which waveform applications are executed. A SCA compliant SDR greatly improves the portability, reusability and interoperability of waveforms applications between different SDR implementations.The multiprocessor system on chip (MPSoC) consisting of large, heterogeneous sets of embedded processors, reconfiguration hardware and network-on-chip (NoC) interconnection is emerging as a potential solution for the continued increase in the data processing bandwidth, as well as expenses for the manufacturing and design of nanoscale system-on-chip (SoC) in the face of continued time-to-market pressures.We studied the challenges of efficiently deploying a SCA compliant platform on an MPSoC. We conclude that for realizing efficiently an SDR system with high data bandwidth requirement, a design flow with systematic design space exploration and optimization, and an efficient programming model are necessary. We propose a hybrid programming model combining distributed client/server model and parallel shared memory model. A design flow is proposed which also integrates a NoC topology synthesis engine for applications that are to be accelerated with parallel programming and multiple processing elements (PEs). We prototyped an integrated SW/HW development environment in which a CORBA based integrated distributed system is developed which depends on the network-on-chip for protocol/packet routing, and software components are deployed with unified interface despite the underlying heterogeneous architecture and os; while the hardware components (processors, IPs, etc) are integrated through interface conforming to the Open Core Protocol (OCP).
57

Simulation of a Wireless Communication System in GNU Radio vs Matlab Simulink : Simulating IEEE 802.11 and 4G

Levin, Bashar January 2024 (has links)
Denna studie genomför en detaljerad undersökning av två olika plattformar för programvarudefinierad radio (SDR), GNU Radio och Simulink, för att avgöra vilken som är mest lämpad för integration i en specifik kurs inom läroplanen vid mittuniversitet. Utvärderingen fokuserar på nyckelprestandamått såsom beräkningskapacitet, simuleringens hastighet och visualiseringsförmåga, vilket ger en omfattande jämförelse mellan dessa två plattformar. Undersökningen inleds med att simulera det fysiska lagret av WiFi, vilket är ett grundläggande krav för kursens laboratoriearbete. Studiens omfattning utvidgas sedan för att inkludera simuleringar av andra nätverkstekniker som 4G. Denna expansion syftar till att samla in omfattande data för en mer noggrann jämförelse och för att grundligt utvärdera varje plattforms förmåga att hantera olika nätverkssimuleringar. Dessutom fördjupar studien sig i olika simuleringstekniker genom att diskutera två distinkta angreppssätt till SDR-simuleringar, vilket belyser deras respektive styrkor och tillämpbarhet i ett utbildningssammanhang. Det slutgiltiga målet med denna forskning är att avgöra om GNU Radio erbjuder betydande fördelar jämfört med MATLABs Simulink och om det bör ersätta Simulink som det primära verktyget som används i denna kurs. I förväntan på potentiella förändringar har nya alternativa laborationsinstruktioner för GNU Radio också utvecklats och presenterats. Dessa instruktioner är utformade för att underlätta en smidig övergång om universitetet beslutar att anta GNU Radio, för att säkerställa att utbildningsmålen fortsätter att uppnås på ett effektivt och effektivt sätt. Även om studien visar att GNU Radio erbjuder bättre beräkningskapacitet var själva simuleringsprocessen något svårare. De två plattformarna uppnådde nästan samma resultat, men GNU Radio krävde extra arbete. Med tanke på att inlärningsresultaten var liknande men inlärningsprocessen med GNU Radio var mer komplicerad bedömdes GNU Radio som olämplig för denna kurs. / This study conducts a detailed examination of two distinct Software Defined Radio (SDR) platforms, GNU Radio and Simulink, to ascertain which is more suited for integration into a specific course within the curriculum at Mid University. The evaluation focuses on key performance metrics such as computing efficiency, simulation speed, and visualization capabilities, providing a comprehensive comparison between these two platforms. The investigation begins by simulating the physical layer of WiFi, which is a fundamental requirement of the course laboratory work. The scope of the study is then broadened to include simulations of other network technologies like 4G. This expansion aims to collect extensive data for a more accurate comparison and to thoroughly evaluate the capabilities of each platform in handling various network simulations. Moreover, the study delves into different simulation methodologies by discussing two distinct approaches to SDR simulations, highlighting their respective strengths and applicabilities in an educational context. The ultimate objective of this study is to determine whether GNU Radio offers a significant advantage over MATLAB’s Simulink and if it should replace Simulink as the primary tool used in this course. In anticipation of potential changes, new alternative laboratory instructions for GNU Radio are also developed and presented. These instructions are designed to facilitate a smooth transition should the university decide to adopt GNU Radio, ensuring that educational goals continue to be met efficiently and effectively. While the study shows that GNU Radio offers better computing efficiency, the process of simulating was somewhat more challenging. The two platforms accomplished almost the same tasks, but GNU Radio required extra effort. Considering that the learning outcomes were similar but the learning process with GNU Radio was more difficult, GNU Radio was deemed unsuitable for this course.
58

Cronologia e mudança cultural na RDS Amanã (Amazonas): um estudo sobre a fase Caiambé da Tradição Borda Incisa / Chronology and cultural change in SDR Amanã (Amazonas): a study on the Caiambé Phase of Incised Rim Tradicion

Santos, Jaqueline Gomes 26 October 2015 (has links)
A tradição Borda Incisa envolve um debate intenso entre os pesquisadores por uma série de motivos, dentre os quais, por suas cerâmicas apresentarem uma grande variabilidade estilística e morfológica, devido sua ampla distribuição geográfica e sua associação aos contextos de terra preta. Na Amazônia Central o período relacionado às ocupações Borda Incisa é considerado de adensamento populacional e quando as mudanças nas paisagens são mais intensas, associadas aos falantes de línguas Arawak que teriam desenvolvido um sistema regional multiétnico com circulação de cerâmicas e compartilhamento de uma mesma cosmologia baseada na ocupação de aldeias circulares. A Reserva de Desenvolvimento Sustentável Amanã, área focal dessa pesquisa, é uma unidade de conservação localizada na porção central do Estado do Amazonas. O objetivo da dissertação é contribuir para a construção de uma história cultural do Lago Amanã e a compreensão de sua antiga e intensa ocupação pré-colonial. A fase Caiambé é o recorte de análise, a partir do refinamento de suas características estilísticas e contextuais, procura-se compreender seus significados no quadro cronológico da Amazônia Central e suas relações com os complexos culturais anteriores e posteriores a ela. Através de escavações, datações e tratamento do material cerâmico, buscou-se oferecer refinamento da cronologia de ocupação. Alguns dos resultados apresentados são: contemporaneidade de assentamentos, caracterização de sítios com diferentes funções e maior caracterização da tecnologia de produção cerâmica. Com base nessas informações sugere-se a fase Caiambé no lago Amanã representa o ápice da ocupação integral de um território, com a formação de diferentes aldeias e espaços públicos e rituais. / The Incised Rim tradition involves an intense debate among researchers for a number of reasons, among which, for its ceramics present a great stylistic and morphological variability due to its wide geographic distribution and their association with terra preta contexts. In central Amazonia the period related to occupations Incised Rim is considered population density and when changes in the landscapes are more intense, associated with the Arawak language speakers who have developed a multi-ethnic regional system with circulation ceramics and sharing the same cosmology based on occupation of circular villages. The Amana Sustainable Development Reserve, focal area of this research is a protected area located in the central portion of the state of Amazonas. The purpose of this work is to contribute to building a cultural history of the Lake Amana and understanding of its ancient and intense precolonial occupation. The Caiambé phase is the analysis of cut from the refinement of its stylistic and contextual features, try to understand their meaning in the chronological framework of the Central Amazon and its relations with the previous cultural complexes and subsequent to it. Through excavation, dating and treatment of ceramic material, it sought to provide refinement of the chronology of occupation. Some of the results are presented: contemporary settlements, characterization of sites with different functions and improved characterization of pottery production technology. Based on this information it is suggested to Caiambé phase at Lake Amana is the culmination of the full occupation of a territory, with the formation of different villages and public spaces and rituals.
59

An Assessment of Available Software Defined Radio Platforms Utilizing Iterative Algorithms

Ferreira, Nathan 04 May 2015 (has links)
As the demands of communication systems have become more complex and varied, software defined radios (SDR) have become increasingly popular. With behavior that can be modified in software, SDR's provide a highly flexible and configurable development environment. Despite its programmable behavior, the maximum performance of an SDR is still rooted in its hardware. This limitation and the desire for the use of SDRs in different applications have led to the rise of various pieces of hardware to serve as SDR platforms. These platforms vary in aspects such as their performance limitations, implementation details, and cost. In this way the choice of SDR platform is not solely based on the cost of the hardware and should be closely examined before making a final decision. This thesis examines the various SDR platform families available on the market today and compares the advantages and disadvantages present for each during development. As many different types of hardware can be considered an option to successfully implement an SDR, this thesis specifically focuses on general purpose processors, system on chip, and field-programmable gate array implementations. When examining these SDR families, the Freescale BSC9131 is chosen to represent the system on chip implementation, while the Nutaq PicoSDR 2x2 Embedded with Virtex6 SX315 is used for the remaining two options. In order to test each of these platforms, a Viterbi algorithm is implemented on each and the performance measured. This performance measurement considers both how quickly the platform is able to perform the decoding, as well as its bit error rate performance in order to ascertain the implementations' accuracy. Other factors considered when comparing each platform are its flexibility and the amount of options available for development. After testing, the details of each implementation are discussed and guidelines for choosing a platform are suggested.
60

Leveraging Software-Defined Radio for a Scalable Wide-band Wireless Channel Measurement System

Jamison, James 01 January 2018 (has links)
Wireless channel characterization is important for determining both the requirements for a wireless system and its resulting reliability. Wireless systems are becoming ever more pervasive and thus are expected to operate in increasingly more cluttered environments. While these devices may be fixed in location, the channel is still far from ideal due to multipath. Under such conditions, it is desirable to have a means of taking wireless channel measurements in a low-cost and distributed manner, which is not always possible using typical channel measurement equipment. This thesis leverages a software-defined radio (SDR) platform to perform wideband wireless channel measurements. Specifically, the system can measure the scalar frequency response of a wireless channel in a distributed manner and provides measurements with an average mean-squared error of 0.018 % σ and a median error not exceeding 0.631 dB when compared to measurements taken with a vector network analyzer. This accuracy holds true in a highly multipath environment, with a measurement range of ~40 dB. The system is also capable of scaling to multiple wireless links which will be measured simultaneously (up to three links are demonstrated). After validating the measurement system, a measurement campaign is undertook using the system in a highly multipath environment to demonstrate a possible application of the system.

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