113 research outputs found

    Combined Time, Frecuency and Space Diversity in Multimedia Mobile Broadcasting Systems

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    El uso combinado de diversidad en el dominio temporal, frecuencial y espacial constituye una valiosa herramienta para mejorar la recepción de servicios de difusión móviles. Gracias a la mejora conseguida por las técnicas de diversidad es posible extender la cobertura de los servicios móviles además de reducir la infraestructura de red. La presente tesis investiga el uso de técnicas de diversidad para la provisión de servicios móviles en la familia europea de sistemas de difusión terrestres estandarizada por el prpoyecto DVB (Digital Video Broadcasting). Esto incluye la primera y segunda generación de sistemas DVB-T (Terrestrial), DVB-NGH (Handheld), y DVB-T2 (Terrestrial 2nd generation), así como el sistema de siguiente generación DVB-NGH. No obstante, el estudio llevado a cabo en la tesis es genérico y puede aplicarse a futuras evoluciones de estándares como el japonés ISDB-T o el americano ATSC. Las investigaciones realizadas dentro del contexto de DVB-T, DVB-H y DVBT2 tienen como objetivo la transmisión simultánea de servicios fijos y móviles en redes terrestres. Esta Convergencia puede facilitar la introducción de servicios móviles de TB debido a la reutilización de espectro, contenido e infraestructura. De acuerdo a los resultados, la incorporación de entrelazado temporal en la capa física para diversidad temporal, y de single-input multiple-output (SIMO) para diversidad espacial, son esenciales para el rendimiento de sistemas móviles de difusión. A pesar de que las técnicas upper later FEC (UL-FEC) pueden propocionar diversidad temporal en sistemas de primera generación como DVB-T y DVB-H, requieren la transmisión de paridad adicional y no son útiles para la recepción estática. El análisis en t�ñerminos de link budjget revela que las técnicas de diversidad noson suficientes para facilitar la provision de servicios móviles en redes DVB-T y DVB-T2 planificadas para recepción fija. Sin embargo, el uso de diversidad en redes planificadas para recepción portableGozálvez Serrano, D. (2012). Combined Time, Frecuency and Space Diversity in Multimedia Mobile Broadcasting Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16273Palanci

    Design of a simulation platform to test next generation of terrestrial DVB

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    Digital Terrestrial Television Broadcasting (DTTB) is a member of our daily life routine, and nonetheless, according to new users’ necessities in the fields of communications and leisure, new challenges are coming up. Moreover, the current Standard is not able to satisfy all the potential requirements. For that reason, first of all, a review of the current Standard has been performed within this work. Then, it has been identified the needing of developing a new version of the standard, ready to support enhanced services, as for example broadcasting transmissions to moving terminals or High Definition Television (HDTV) transmissions, among others. The main objective of this project is the design and development of a physical layer simulator of the whole DVB-T standard, including both the complete transmission and reception procedures. The simulator has been developed in Matlab. A detailed description of the simulator both from a functional and an architectural point of view is included. The simulator is the base for testing any possible modifications that may be included into the DVB-T2 future standard. In fact, several proposed enhancements have already been carried out and their performance has been evaluated. Specifically, the use of higher order modulation schemes, and the corresponding modifications in all the system blocks, have been included and evaluated. Furthermore, the simulator will allow testing other enhancements as the use of more efficient encoders and interleavers, MIMO technologies, and so on. A complete set of numerical results showing the performance of the different parts of the system, are presented in order to validate the correctness of the implementation and to evaluate both the current standard performance and the proposed enhancements. This work has been performed within the context of a project called FURIA, which is a strategic research project funded by the Spanish Ministry of Industry, Tourism and Commerce. A brief description of this project and its consortium has been also included herein, together with an introduction to the current situation of the DTTB in Spain (called TDT in Spanish)

    Cross-layer Optimized Wireless Video Surveillance

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    A wireless video surveillance system contains three major components, the video capture and preprocessing, the video compression and transmission over wireless sensor networks (WSNs), and the video analysis at the receiving end. The coordination of different components is important for improving the end-to-end video quality, especially under the communication resource constraint. Cross-layer control proves to be an efficient measure for optimal system configuration. In this dissertation, we address the problem of implementing cross-layer optimization in the wireless video surveillance system. The thesis work is based on three research projects. In the first project, a single PTU (pan-tilt-unit) camera is used for video object tracking. The problem studied is how to improve the quality of the received video by jointly considering the coding and transmission process. The cross-layer controller determines the optimal coding and transmission parameters, according to the dynamic channel condition and the transmission delay. Multiple error concealment strategies are developed utilizing the special property of the PTU camera motion. In the second project, the binocular PTU camera is adopted for video object tracking. The presented work studied the fast disparity estimation algorithm and the 3D video transcoding over the WSN for real-time applications. The disparity/depth information is estimated in a coarse-to-fine manner using both local and global methods. The transcoding is coordinated by the cross-layer controller based on the channel condition and the data rate constraint, in order to achieve the best view synthesis quality. The third project is applied for multi-camera motion capture in remote healthcare monitoring. The challenge is the resource allocation for multiple video sequences. The presented cross-layer design incorporates the delay sensitive, content-aware video coding and transmission, and the adaptive video coding and transmission to ensure the optimal and balanced quality for the multi-view videos. In these projects, interdisciplinary study is conducted to synergize the surveillance system under the cross-layer optimization framework. Experimental results demonstrate the efficiency of the proposed schemes. The challenges of cross-layer design in existing wireless video surveillance systems are also analyzed to enlighten the future work. Adviser: Song C

    Cross-layer Optimized Wireless Video Surveillance

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    A wireless video surveillance system contains three major components, the video capture and preprocessing, the video compression and transmission over wireless sensor networks (WSNs), and the video analysis at the receiving end. The coordination of different components is important for improving the end-to-end video quality, especially under the communication resource constraint. Cross-layer control proves to be an efficient measure for optimal system configuration. In this dissertation, we address the problem of implementing cross-layer optimization in the wireless video surveillance system. The thesis work is based on three research projects. In the first project, a single PTU (pan-tilt-unit) camera is used for video object tracking. The problem studied is how to improve the quality of the received video by jointly considering the coding and transmission process. The cross-layer controller determines the optimal coding and transmission parameters, according to the dynamic channel condition and the transmission delay. Multiple error concealment strategies are developed utilizing the special property of the PTU camera motion. In the second project, the binocular PTU camera is adopted for video object tracking. The presented work studied the fast disparity estimation algorithm and the 3D video transcoding over the WSN for real-time applications. The disparity/depth information is estimated in a coarse-to-fine manner using both local and global methods. The transcoding is coordinated by the cross-layer controller based on the channel condition and the data rate constraint, in order to achieve the best view synthesis quality. The third project is applied for multi-camera motion capture in remote healthcare monitoring. The challenge is the resource allocation for multiple video sequences. The presented cross-layer design incorporates the delay sensitive, content-aware video coding and transmission, and the adaptive video coding and transmission to ensure the optimal and balanced quality for the multi-view videos. In these projects, interdisciplinary study is conducted to synergize the surveillance system under the cross-layer optimization framework. Experimental results demonstrate the efficiency of the proposed schemes. The challenges of cross-layer design in existing wireless video surveillance systems are also analyzed to enlighten the future work. Adviser: Song C

    Design of a simulation platform to test next generation of terrestrial DVB

    Get PDF
    Digital Terrestrial Television Broadcasting (DTTB) is a member of our daily life routine, and nonetheless, according to new users’ necessities in the fields of communications and leisure, new challenges are coming up. Moreover, the current Standard is not able to satisfy all the potential requirements. For that reason, first of all, a review of the current Standard has been performed within this work. Then, it has been identified the needing of developing a new version of the standard, ready to support enhanced services, as for example broadcasting transmissions to moving terminals or High Definition Television (HDTV) transmissions, among others. The main objective of this project is the design and development of a physical layer simulator of the whole DVB-T standard, including both the complete transmission and reception procedures. The simulator has been developed in Matlab. A detailed description of the simulator both from a functional and an architectural point of view is included. The simulator is the base for testing any possible modifications that may be included into the DVB-T2 future standard. In fact, several proposed enhancements have already been carried out and their performance has been evaluated. Specifically, the use of higher order modulation schemes, and the corresponding modifications in all the system blocks, have been included and evaluated. Furthermore, the simulator will allow testing other enhancements as the use of more efficient encoders and interleavers, MIMO technologies, and so on. A complete set of numerical results showing the performance of the different parts of the system, are presented in order to validate the correctness of the implementation and to evaluate both the current standard performance and the proposed enhancements. This work has been performed within the context of a project called FURIA, which is a strategic research project funded by the Spanish Ministry of Industry, Tourism and Commerce. A brief description of this project and its consortium has been also included herein, together with an introduction to the current situation of the DTTB in Spain (called TDT in Spanish)

    Single-Frequency Network Terrestrial Broadcasting with 5GNR Numerology

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    L'abstract è presente nell'allegato / the abstract is in the attachmen

    COST EFFICIENT PROVISIONING OF MASS MOBILE MULTIMEDIA SERVICES IN HYBRID CELLULAR AND BROADCASTING SYSTEMS

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    Uno de los retos a los que se enfrenta la industria de las comunicaciones móviles e inalámbricas es proporcionar servicios multimedia masivos a bajo coste, haciéndolos asequibles para los usuarios y rentables a los operadores. El servicio más representativo es el de TV móvil, el cual se espera que sea una aplicación clave en las futuras redes móviles. Actualmente las redes celulares no pueden soportar un consumo a gran escala de este tipo de servicios, y las nuevas redes de radiodifusión móvil son muy costosas de desplegar debido a la gran inversión en infraestructura de red necesaria para proporcionar niveles aceptables de cobertura. Esta tesis doctoral aborda el problema de la provisión eficiente de servicios multimedia masivos a dispositivos móviles y portables utilizando la infraestructura de radiodifusión y celular existente. La tesis contempla las tecnologías comerciales de última generación para la radiodifusión móvil (DVB-H) y para las redes celulares (redes 3G+ con HSDPA y MBMS), aunque se centra principalmente en DVB-H. El principal paradigma propuesto para proporcionar servicios multimedia masivos a bajo coste es evitar el despliegue de una red DVB-H con alta capacidad y cobertura desde el inicio. En su lugar se propone realizar un despliegue progresivo de la infraestructura DVB-H siguiendo la demanda de los usuarios. Bajo este contexto, la red celular es fundamental para evitar sobre-dimensionar la red DVB-H en capacidad y también en áreas con una baja densidad de usuarios hasta que el despliegue de un transmisor o un repetidor DVB-H sea necesario. Como principal solución tecnológica la tesis propone realizar una codificación multi-burst en DVB-H utilizando códigos Raptor. El objetivo es explotar la diversidad temporal del canal móvil para aumentar la robustez de la señal y, por tanto, el nivel de cobertura, a costa de incrementar la latencia de la red.Gómez Barquero, D. (2009). COST EFFICIENT PROVISIONING OF MASS MOBILE MULTIMEDIA SERVICES IN HYBRID CELLULAR AND BROADCASTING SYSTEMS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/6881Palanci

    Cognitive Radio Systems

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    Cognitive radio is a hot research area for future wireless communications in the recent years. In order to increase the spectrum utilization, cognitive radio makes it possible for unlicensed users to access the spectrum unoccupied by licensed users. Cognitive radio let the equipments more intelligent to communicate with each other in a spectrum-aware manner and provide a new approach for the co-existence of multiple wireless systems. The goal of this book is to provide highlights of the current research topics in the field of cognitive radio systems. The book consists of 17 chapters, addressing various problems in cognitive radio systems

    Architectures multi-Asip pour turbo récepteur flexible

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    Rapidly evolving wireless standards use modern techniques such as turbo codes, Bit Interleaved coded Modulation (BICM), high order QAM constellation, Signal Space Diversity (SSD), Multi-Input Multi-Output (MIMO) Spatial Multiplexing (SM) and Space Time Codes (STC) with different parameters for reliable high rate data transmissions. Adoption of such techniques in the transmitter can impact the receiver architecture in three ways: (1) the complex processing related to advanced techniques such as turbo codes, encourage to perform iterative processing in the receiver to improve error rate performance (2) to satisfy high throughput requirement for an iterative receiver, parallel processing is mandatory and finally (3) to allow the support of different techniques and parameters imposed, programmable yet high throughput hardware processing elements are required. In this thesis, to address the high throughput requirement with turbo processing, first of all a study of parallelism on turbo decoding is extended for turbo demodulation and turbo equalization. Based on the results acquired from the parallelism study a flexible high throughput heterogeneous multi-ASIP NoC based unified turbo receiver is proposed. The proposed architecture fulfils the target requirements in a way that: (a) Application Specific Instruction-set Processor (ASIP) exploits metric generation level parallelism and implements the required flexibility, (b) throughputs beyond the capacity of single ASIP in a turbo process are achieved through multiple ASIP elements implementing sub-block parallelism and shuffled processing and finally (c) Network on Chip is used to handle communication conflicts during parallel processing of multiple ASIPs. In pursuit to achieve a hardware model of the proposed architecture two ASIPs are conceived where the first one, namely EquASIP, is dedicated for MMSE-IC equalization and provides a flexible solution for multiple MIMO techniques adopted in multiple wireless standards with a capability to work in turbo equalization context. The second ASIP, named as DemASIP, is a flexible demapper which can be used in MIMO or single antenna environment for any modulation till 256-QAM with or without iterative demodulation. Using available TurbASIP and NoC components, the thesis concludes on an FPGA prototype of heterogeneous multi-ASIP NoC based unified turbo receiver which integrates 9 instances of 3 different ASIPs with 2 NoCs.Les normes de communication sans fil, sans cesse en évolution, imposent l'utilisation de techniques modernes telles que les turbocodes, modulation codée à entrelacement bit (BICM), constellation MAQ d'ordre élevé, diversité de constellation (SSD), multiplexage spatial et codage espace-temps multi-antennes (MIMO) avec des paramètres différents pour des transmissions fiables et de haut débit. L'adoption de ces techniques dans l'émetteur peut influencer l'architecture du récepteur de trois façons: (1) les traitement complexes relatifs aux techniques avancées comme les turbocodes, encourage à effectuer un traitement itératif dans le récepteur pour améliorer la performance en termes de taux d'erreur (2) pour satisfaire l'exigence de haut débit avec un récepteur itératif, le recours au parallélisme est obligatoire et enfin (3) pour assurer le support des différentes techniques et paramètres imposées, des processeurs de traitement matériel flexibles, mais aussi de haute performance, sont nécessaires. Dans cette thèse, pour répondre aux besoins de haut débit dans un contexte de traitement itératif, tout d'abord une étude de parallélisme sur le turbo décodage a été étendue aux applications de turbo démodulation et turbo égalisation. Partant des résultats obtenus à partir de l'étude du parallélisme, un récepteur itératif unifié basé sur un modèle d'architecture multi-ASIP hétérogène intégrant un réseau sur puce (NoC) a été proposé. L'architecture proposée répond aux exigences visées d'une manière où: (a) le concept de processeur à jeu d'instruction dédié à l'application (ASIP) exploite le parallélisme du niveau de génération de métriques et met en oeuvre la flexibilité nécessaire, (b) les débits au-delà de la capacité d'un seul ASIP dans un processus itératif sont obtenus au moyen de multiples ASIP implémentant le parallélisme de sous-blocs et le traitement combiné et enfin (c) le concept de réseau sur puce (NoC) est utilisé pour gérer les conflits de communication au cours du traitement parallèle itératif multi-ASIP. Dans le but de parvenir à un modèle matériel de l'architecture proposée, deux ASIP ont été conçus où le premier, nommé EquASIP, est dédié à l'égalisation MMSE-IC et fournit une solution flexible pour de multiples techniques multi-antennes adoptés dans plusieurs normes sans fil avec la capacité de travailler dans un contexte de turbo égalisation. Le deuxième ASIP, nommé DemASIP, est un démappeur flexible qui peut être utilisé dans un environnement multi-antennes et pour tout type de modulation jusqu'à MAQ-256 avec ou sans démodulation itérative. En intégrant ces ASIP, en plus des NoC et TurbASIP disponibles à Télécom Bretagne, la thèse conclut sur un prototype FPGA d'un récepteur itératif unifié multi-ASIP qui intègre 9 coeurs de 3 différents types d'ASIP avec 2 NoC
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