A survey of digital television broadcast transmission techniques

This paper is a survey of the transmission techniques used in digital television (TV) standards worldwide. With the increase in the demand for High-Definition (HD) TV, video-on-demand and mobile TV services, there was a real need for more bandwidth-efficient, flawless and crisp video quality, which motivated the migration from analogue to digital broadcasting. In this paper we present a brief history of the development of TV and then we survey the transmission technology used in different digital terrestrial, satellite, cable and mobile TV standards in different parts of the world. First, we present the Digital Video Broadcasting standards developed in Europe for terrestrial (DVB-T/T2), for satellite (DVB-S/S2), for cable (DVB-C) and for hand-held transmission (DVB-H). We then describe the Advanced Television System Committee standards developed in the USA both for terrestrial (ATSC) and for hand-held transmission (ATSC-M/H). We continue by describing the Integrated Services Digital Broadcasting standards developed in Japan for Terrestrial (ISDB-T) and Satellite (ISDB-S) transmission and then present the International System for Digital Television (ISDTV), which was developed in Brazil by adopteding the ISDB-T physical layer architecture. Following the ISDTV, we describe the Digital Terrestrial television Multimedia Broadcast (DTMB) standard developed in China. Finally, as a design example, we highlight the physical layer implementation of the DVB-T2 standar

Design and Analysis of Forward Error Control Coding and Signaling for Guaranteeing QoS in Wireless Broadcast Systems

Broadcasting systems are networks where the transmission is received by several terminals. Generally broadcast receivers are passive devices in the network, meaning that they do not interact with the transmitter. Providing a certain Quality of Service (QoS) for the receivers in heterogeneous reception environment with no feedback is not an easy task. Forward error control coding can be used for protection against transmission errors to enhance the QoS for broadcast services. For good performance in terrestrial wireless networks, diversity should be utilized. The diversity is utilized by application of interleaving together with the forward error correction codes. In this dissertation the design and analysis of forward error control and control signalling for providing QoS in wireless broadcasting systems are studied. Control signaling is used in broadcasting networks to give the receiver necessary information on how to connect to the network itself and how to receive the services that are being transmitted. Usually control signalling is considered to be transmitted through a dedicated path in the systems. Therefore, the relationship of the signaling and service data paths should be considered early in the design phase. Modeling and simulations are used in the case studies of this dissertation to study this relationship. This dissertation begins with a survey on the broadcasting environment and mechanisms for providing QoS therein. Then case studies present analysis and design of such mechanisms in real systems. The mechanisms for providing QoS considering signaling and service data paths and their relationship at the DVB-H link layer are analyzed as the first case study. In particular the performance of different service data decoding mechanisms and optimal signaling transmission parameter selection are presented. The second case study investigates the design of signaling and service data paths for the more modern DVB-T2 physical layer. Furthermore, by comparing the performances of the signaling and service data paths by simulations, configuration guidelines for the DVB-T2 physical layer signaling are given. The presented guidelines can prove useful when configuring DVB-T2 transmission networks. Finally, recommendations for the design of data and signalling paths are given based on findings from the case studies. The requirements for the signaling design should be derived from the requirements for the main services. Generally, these requirements for signaling should be more demanding as the signaling is the enabler for service reception.Siirretty Doriast

On Transmission System Design for Wireless Broadcasting

This thesis considers aspects related to the design and standardisation of transmission systems for wireless broadcasting, comprising terrestrial and mobile reception. The purpose is to identify which factors influence the technical decisions and what issues could be better considered in the design process in order to assess different use cases, service scenarios and end-user quality. Further, the necessity of cross-layer optimisation for efficient data transmission is emphasised and means to take this into consideration are suggested. The work is mainly related terrestrial and mobile digital video broadcasting systems but many of the findings can be generalised also to other transmission systems and design processes. The work has led to three main conclusions. First, it is discovered that there are no sufficiently accurate error criteria for measuring the subjective perceived audiovisual quality that could be utilised in transmission system design. Means for designing new error criteria for mobile TV (television) services are suggested and similar work related to other services is recommended. Second, it is suggested that in addition to commercial requirements there should be technical requirements setting the frame work for the design process of a new transmission system. The technical requirements should include the assessed reception conditions, technical quality of service and service functionalities. Reception conditions comprise radio channel models, receiver types and antenna types. Technical quality of service consists of bandwidth, timeliness and reliability. Of these, the thesis focuses on radio channel models and errorcriteria (reliability) as two of the most important design challenges and provides means to optimise transmission parameters based on these. Third, the thesis argues that the most favourable development for wireless broadcasting would be a single system suitable for all scenarios of wireless broadcasting. It is claimed that there are no major technical obstacles to achieve this and that the recently published second generation digital terrestrial television broadcasting system provides a good basis. The challenges and opportunities of a universal wireless broadcasting system are discussed mainly from technical but briefly also from commercial and regulatory aspectSiirretty Doriast

An overview on the standard of digital video broadcasting – terrestrial.

Digital Video Broadcasting (DVB) es un consorcio formado por industriales de los medios de comunicación, que está integrado por radiodifusores, fabricantes, operadores de redes, desarrolladores de software y organismos reguladores. El consorcio fue creado con el fin de definir las normas técnicas para estandarizar todos los aspectos relacionados con la prestación de servicios de televisión digital. El estándar DVB ha sido adoptado en Europa, Oriente Medio, Suráfrica y Australasia. Adicionalmente, el estándar DVB fue seleccionado en Colombia y Panamá como el sistema de transmisión de televisión digital terrestre (DVB-T/T2). El estándar DVB es un conjunto de especificaciones que permiten la integración de información multimedia para proveer servicios de información, educación, negocios y entretenimiento. La implementación de DVB requiere de acuerdos entre los radiodifusores, operadores de redes y fabricantes en la definición de los parámetros de operación, además de tener en cuenta las normativas gubernamentales. Este artículo presenta un resumen de los principales elementos definidos en el estándar DVB-T/T2, basado en los documentos guía elaborados por el consorcio DVB, e incluye algunas de las acciones tomadas durante el proceso de implementación de DVB-T/T2 en Colombia

A Study on Hierarchical Transmission Method for Additional Service of Advanced T-DMB System

The quality of traditional analog radio broadcasting systems has significantly deteriorated in recent years, due to serious electromagnetic pollution in urban areas, especially in mobile environments. Among the new broadcasting systems, Digital Audio Broadcasting (DAB), which is based on the Eureka-147 standard, provides CD-quality audio broadcasting services for fixed, portable and mobile applications, and has been recognized as a promising solution. Recently, the DAB system was announced as the official transmission specification of the Digital Multimedia Broadcasting (DMB) system in Korea. The DMB system has a 1.7Mbps throughput, which is sufficient for multimedia broadcasting services as well as CD-quality digital audio services. However, the throughput is reduced to 1.152Mbps when we take into account the overhead such as bits needed for synchronization, error correction and multiplex configuration information. Therefore, multimedia broadcasting services have a low throughput. Recently, there is a need to upgrade the conventional T-DMB system, in order to provide additional services and a higher throughput for multimedia broadcasting services. In this thesis, we propose a structure for an advanced T-DMB (AT-DMB) system, which is based on Eureka-147, with UEP coding methods and hierarchical 16QAM/64QAM modulation, to provide additional services while maintaining the BER performance. A hierarchical modulation scheme, strong channel code and unequal error protection (UEP) are applied to the conventional T-DMB system, in order to enhance the conventional T-DMB system and provide additional mobile user services. Furthermore, this thesis proposes a non-uniform 16QAM/64QAM modulation scheme combined with various bit splitting methods and coding methods such as iterative codes. The conventional T-DMB system based on Eureka-147 has the approved serial concatenated coding scheme. This thesis also applies the serial concatenated coding scheme as an HP(High priority) stream coding scheme, in order to provide a continuous conventional T-DMB service to subscribers. The performance gap between HP and LP(Low priority) streams is very large. This means that the performance of the HP and LP streams involves trade-offs, when applying the same coding method. If the performance of the LP stream is poor, there is no point in providing the LP stream to subscribers. Therefore, this thesis focuses on reducing the performance gap between the HP and LP streams. This is why this thesis applies iterative codes to the LP stream. Among iterative codes, double binary turbo codes and LDPC (low density parity check) codes are good candidates for the AT-DMB system, because they approach the Shannon limit performance and involve a simple puncturing device and a flexible block size/coding rate combination. The proposed AT-DMB system model with the UEP coding method, hierarchical modulation and bit splitting method provides a means of achieving high performance, multimedia broadcasting via the conventional T-DMB system.제 1 장 서론 = 1 제 2 장 지상파 DMB 시스템 모델 = 3 제 3 장 차세대 지상파 DMB 시스템 모델 = 7 제 3-1 절 차세대 지상파 DMB 시스템 개발의 필요성과 개념 = 7 제 3-2 절 계층적 변조방식 = 10 제 3-3 절 UEP(Unequal Error Protection) 시스템 = 14 제 4 장 부가서비스 복조를 위한 비트분리방법 = 17 제 4-1 절 LLR 방법 = 18 제 4-2 절 MAX 방법 = 21 제 4-3 절 Center focusing 방법 = 22 제 4-4 절 복잡도 비교 = 24 제 5 장 부가서비스에 고려되는 채널 부호화방법 = 25 제 5-1 절 Double binary turbo 부호 = 26 제 5-2 절 DVB-S2 규격의 LDPC 부호 = 31 제 5-3 절 IEEE 802.16e에 적용된 LDPC 부호 = 37 제 6 장 시뮬레이션 결과 = 40 제 6-1 절 시뮬레이션 파라메터 = 40 제 6-2 절 비트분리 방법에 따른 시뮬레이션 결과 = 42 제 6-3 절 부가서비스의 부호화 방식에 따른 시뮬레이션 결과 = 44 제 7 장 결론 = 54 참고문헌 = 5

Solutions for New Terrestrial Broadcasting Systems Offering Simultaneously Stationary and Mobile Services

221 p.[EN]Since the first broadcasted TV signal was transmitted in the early decades of the past century, the television broadcasting industry has experienced a series of dramatic changes. Most recently, following the evolution from analogue to digital systems, the digital dividend has become one of the main concerns of the broadcasting industry. In fact, there are many international spectrum authorities reclaiming part of the broadcasting spectrum to satisfy the growing demand of other services, such as broadband wireless services, arguing that the TV services are not very spectrum-efficient. Apart from that, it must be taken into account that, even if up to now the mobile broadcasting has not been considered a major requirement, this will probably change in the near future. In fact, it is expected that the global mobile data traffic will increase 11-fold between 2014 and 2018, and what is more, over two thirds of the data traffic will be video stream by the end of that period. Therefore, the capability to receive HD services anywhere with a mobile device is going to be a mandatory requirement for any new generation broadcasting system. The main objective of this work is to present several technical solutions that answer to these challenges. In particular, the main questions to be solved are the spectrum efficiency issue and the increasing user expectations of receiving high quality mobile services. In other words, the main objective is to provide technical solutions for an efficient and flexible usage of the terrestrial broadcasting spectrum for both stationary and mobile services. The first contributions of this scientific work are closely related to the study of the mobile broadcast reception. Firstly, a comprehensive mathematical analysis of the OFDM signal behaviour over time-varying channels is presented. In order to maximize the channel capacity in mobile environments, channel estimation and equalization are studied in depth. First, the most implemented equalization solutions in time-varying scenarios are analyzed, and then, based on these existing techniques, a new equalization algorithm is proposed for enhancing the receivers’ performance. An alternative solution for improving the efficiency under mobile channel conditions is treating the Inter Carrier Interference as another noise source. Specifically, after analyzing the ICI impact and the existing solutions for reducing the ICI penalty, a new approach based on the robustness of FEC codes is presented. This new approach employs one dimensional algorithms at the receiver and entrusts the ICI removing task to the robust forward error correction codes. Finally, another major contribution of this work is the presentation of the Layer Division Multiplexing (LDM) as a spectrum-efficient and flexible solution for offering stationary and mobile services simultaneously. The comprehensive theoretical study developed here verifies the improved spectrum efficiency, whereas the included practical validation confirms the feasibility of the system and presents it as a very promising multiplexing technique, which will surely be a strong candidate for the next generation broadcasting services.[ES]Desde el comienzo de la transmisión de las primeras señales de televisión a principios del siglo pasado, la radiodifusión digital ha evolucionado gracias a una serie de cambios relevantes. Recientemente, como consecuencia directa de la digitalización del servicio, el dividendo digital se ha convertido en uno de los caballos de batalla de la industria de la radiodifusión. De hecho, no son pocos los consorcios internacionales que abogan por asignar parte del espectro de radiodifusión a otros servicios como, por ejemplo, la telefonía móvil, argumentado la poca eficiencia espectral de la tecnología de radiodifusión actual. Asimismo, se debe tener en cuenta que a pesar de que los servicios móviles no se han considerado fundamentales en el pasado, esta tendencia probablemente variará en el futuro cercano. De hecho, se espera que el tráfico derivado de servicios móviles se multiplique por once entre los años 2014 y 2018; y lo que es más importante, se pronostica que dos tercios del tráfico móvil sea video streaming para finales de ese periodo. Por lo tanto, la posibilidad de ofrecer servicios de alta definición en dispositivos móviles es un requisito fundamental para los sistemas de radiodifusión de nueva generación. El principal objetivo de este trabajo es presentar soluciones técnicas que den respuesta a los retos planteados anteriormente. En particular, las principales cuestiones a resolver son la ineficiencia espectral y el incremento de usuarios que demandan mayor calidad en los contenidos para dispositivos móviles. En pocas palabras, el principal objetivo de este trabajo se basa en ofrecer una solución más eficiente y flexible para la transmisión simultánea de servicios fijos y móviles. La primera contribución relevante de este trabajo está relacionada con la recepción de la señal de televisión en movimiento. En primer lugar, se presenta un completo análisis matemático del comportamiento de la señal OFDM en canales variantes con el tiempo. A continuación, con la intención de maximizar la capacidad del canal, se estudian en profundidad los algoritmos de estimación y ecualización. Posteriormente, se analizan los algoritmos de ecualización más implementados, y por último, basándose en estas técnicas, se propone un nuevo algoritmo de ecualización para aumentar el rendimiento de los receptores en tales condiciones. Del mismo modo, se plantea un nuevo enfoque para mejorar la eficiencia de los servicios móviles basado en tratar la interferencia entre portadoras como una fuente de ruido. Concretamente, tras analizar el impacto del ICI en los receptores actuales, se sugiere delegar el trabajo de corrección de dichas distorsiones en códigos FEC muy robustos. Finalmente, la última contribución importante de este trabajo es la presentación de la tecnología LDM como una manera más eficiente y flexible para la transmisión simultánea de servicios fijos y móviles. El análisis teórico presentado confirma el incremento en la eficiencia espectral, mientras que el estudio práctico valida la posible implementación del sistema y presenta la tecnología LDM c

Video Multicasting Over 3g/umts Networks

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2009Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2009Bu çalışmada, UMTS şebekelerinde kullanılan farklı çeşitteki çoğa gönderim teknolojileri olumlu ve olumsuz yanları ile birlikte açıklanmıştır. 3GPP standardı, çoklu dağıtımı desteklemek için MBMS (Multimedia Broadcast/Multicast Services – Çoğul Ortam Yayın ve Çoklu Dağıtım Servisi) ile geliştirilmiştir. Bu tez esas olarak MBMS standardı, UMTS şebekelerine uygulanabilen video aktarım protokolleri ve teknikleri ile en önemli çoklu dağıtım servisi olarak görülen mobil televizyon uygulamasına odaklanmıştır. Teknolojik yeniliklerin başarısı ve kullanıcılar tarafından kabulü önemli ölçüde içeriğe dayalıdır. İçerik, kullanıcıların isteklerine göre tasarlanmalıdır ve mobil TV için önemli bir rol oynar. Bu tezde, kullanıcı istekleri ortaya konulmuş ve ayrıca mobil TV teknolojilerinin mevcut durumu, deneme sonuçları ve ticari olarak piyasaya sürülmesi tanımlanmıştır. Hangi durumlarda, nerelerde ve ne zaman bu hizmetlerin kullanılabileceğini tanımlamak için gerçekleştirilen araştırma sonuçları ortaya konulmuştur. Tezin bu konuya katkısı yeniden belirtilip, gelecekteki araştırmalara yön verecek bazı konulardan bahsedilmiştir.In this study different types of multicast technologies which are used in UMTS networks are introduced with their pros and cons. The 3GPP standard has been enhanced with MBMS (Multimedia Broadcast/Multicast Services) to support multicasting. This thesis mainly focuses on MBMS standard, video streaming protocols and techniques that are applicable to UMTS networks and especially the mobile TV service. Success and user acceptance of new technology innovations are highly depend on the content. It needs to be designed according to consumers’ demands and play an important role for mobile TV. In this thesis, users’ demands are introduced, also mobile TV technologies current status, trial results and commercial launches are described. Research results are presented which are performed to define in what situations, where and when the service can be used. The contributions are restated and some insight into future research directions is given.Yüksek LisansM.Sc

Hierarchical MIMO modulation in digital TV transmission

It is possible to use hierarchical modulation in broadcast systems so that there are two different levels of service with different coverage patterns. There is a basic reception quality, which should be available to almost all users in the system, and there is a higher reception quality which should be available for most users in the system. The higher quality is realized by combining the basic signal with an incremental signal. For this, the basic part of the signal should be more robustly encoded than the incremental part. The fundamental tradeoff in hierarchical modulation is between the coverage of the basic signal and the coverage of the incremental signal. Independently of the method used to multiplex the basic and incremental signals, the presence of the incremental signal takes resources from the basic signal or causes interference. Thus the larger the coverage of the incremental signal is, the smaller the coverage of the basic signal becomes. Most digital broadcast standards (DVB-T, DVB-H, LTE MBMS) are based on orthogonal frequency division multiplexing (OFDM) and single-frequency network (SFN) operation. In this thesis, hierarchical modulation for single-antenna transmission is studied from technical point of view, based on a SFN environment, where time division multiplexing (TDM), superposition, hierarchical quadrature amplitude modulation (QAM) and hierarchical multiple-input and multiple-output (MIMO) scheme are illustrated. The alternatives for hierarchical multi-antenna modulation are investigated. The fundamental tradeoff of different hierarchical broadcasting methods are evaluated in MATLAB. This thesis mainly focuses on the progress of hierarchical broadcasting methods and possible improvements that could be made. The aim of this thesis is to improve current digital broadcasting methods by introducing multiple antennas to both transmitter and receiver

Soft-DVB: A Fully-Software DVB-T Modulator Based on the GNU-Radio framework

Introduction Full-Hardware solutions: a heavy burden for further DSP development A real world example: FM Broadcast, persistence of an old technology Modern, Competitive Multimedia Broadcasting Infrastructure: a Wishlist The Full-Software proposal: a bridge between research effort and deployment The Soft-DVB concept implementation: a feasibility proof Advantages of a Fully-Software solution for ETSI DVB-T signal generation 1 The DVB-T Standard for broadcasting terrestrial digital television Main features Typical DVB-T propagation scenarios: Rayleigh and Ricean Channels Analysis of ETSI DVB-T functional blocks 2 The OFDM Modulation Overview Usage within ETSI DVB-T: benefits and implementation choices Orthogonality of Signals and Spectral Efficiency Multipath Resistance 3 Soft-DVB Preliminary choices: The USRP system and the GNURadio Framework Soft-DVB Architecture Development Stages: the check-dumps TPS Implementation Hardware trivia and Headaches On Air... pardon, on Coax Signal Debugging On Air, Actually! 4 Optimization CPU-time vs Memory Trade-Off Bit-Level Operations and the convolutional encoder example Vectorized vs Scalar Structures 5 Implementation Results Laboratory Benchmarks Final Implementation Results 6 Real World Deployment scenarios and Perspectives Emergency Broadcasts Mission-Dedicated Broadcasts Highway Traffic Information Systems Quick and Cheap Network: Ideas for a new Media Broadcasting Model On Site Broadcasting Parallel CPU Architectures: a huge computing power boost 7 Conclusion