Digital video broadcasting over satellite (DVB‐S): a system for broadcasting and contribution applications

The general system concepts for digital television transmission and broadcasting by satellite, developed within the European digital video broadcasting (DVB) Project and standardized by ETSI are described. The system (EN 300 421) is designed to provide direct‐to‐home (DTH) multi‐programme TV services in the BSS and FSS bands and is addressed to consumer integrated receiver decoders (IRDs), as well as collective antenna systems (SMATV) and cable television head‐end stations, with a likelihood of remodulation. The system operational modes have been extended in 1998 (EN 301 210) to cover also ‘contribution’ applications by satellite, such as conveying vision and sound material between TV studios, or from remote locations directly to the broadcaster's premises through light and portable up‐link terminal digital satellite news gathering (DSNG). The exploitation of the multiplex flexibility allows the use of the transmission capacity for a variety of TV service configurations. The use of flexible and advanced error protection techniques, based on the concatenation of Reed‐Solomon and convolutional codes (with Viterbi decoding), allows optimum adaptation to different satellite transponder characteristics, i.e. bandwidth and power, providing high service quality and availability with small receiving antennas (DTH applications) or transmitting terminals (DSNG applications). Copyright © 2000 John Wiley & Sons, Ltd.     

Possible channel coding and modulation system for the satellite broadcasting of a high-definition television signal

A new coding/modulation approach is considered to improve service availability of digital high-definition television (HDTV) satellite broadcasting services at 22 GHz. This approach uses a concept of layered modulation in conjunction with layered picture coding and channel coding. By means of this technique, the service continuity can be extended without the needs for increasing the satellite transmission power, the service quality under severe atmospheric attenuations being reduced from high definition to normal definition.     

Outline of ISDB Systems

Integrated Service Digital Broadcasting (ISDB) is the name of the set of digital broadcasting standards in Japan covering terrestrial, satellite,and cable transmission with common format for multiplexing which enable transmission of high definition television as well as data broadcasting. This paper shows the outline of the standards and the updated service features in Japan.     

Planning considerations for domestic replacement satellites

Several domestic satellite systems have been more than 10 years in operation. During this time, the world has experienced a dramatic growth in communication. While the demand for more telephony and data circuits and television channels is still on the rise, new methods of signal transmission and circuit compression have been developed which may balance or reduce the need for more satellite trunk capacity. And while whole national networks are converting to digital transmission, new transmission media like optical fibre, are finding application, and may take over some of the heavy traffic routes previously carried by satellite. On the other side, business data communication between roof-top terminals, thin route traffic to remote users, television distribution by direct satellite broadcasting are becoming more popular and satellite land mobile communication may soon be a reality. Thus the domestic satellite's role appears to be slowly changing towards thin route and mobile traffic and DBS-type distribution and perhaps even radio position determination. System planners are adapting to the new trends in satellite communication and are trying to accommodate the various service payloads on a single satellite. This article discusses some aspects of the emerging multi-purpose domestic satellite, which carries fixed and mobile services, TV direct broadcasting and radio position determination, in view of network digitalization, network expansion, circuit compression, synchronization. The discussion centres on transponder supply and demand, satellite replenishment, K_u-band vs. C-band for TV direct satellite broadcasting, choice of modulation/multiple access for mobile communication, and expected accuracy in radio position determination.     

关于乡镇模数转换的几点思考

目前全国的城市社区都已经普及了数字电视,但在一些偏远的乡镇,还在使用一些天线、卫星电视接收器等接收模拟电视节目。利用天线等接收设备,只能收看到为数不多的电视频道,在一些特别偏远的地区,甚至接收不到电视信号,更谈不上数字电视,为此就乡镇的模数转换进行讨论,并提出一些建议和想法。     

Digital TV comes down to earth

The introduction of digital television, albeit with only modest pretensions to glitz, is bound to invigorate competition among manufacturers and broadcasters. The BBC and commercial TV companies in Britain will launch what looks to be the world's first terrestrial digital TV (DTTV) service intended for nationwide viewing. The British services will be the first to use ground transmitters to send digital pictures and sound to an ordinary Yagi roof antenna of the type used for analog TV in Europe or even to indoor rabbit ears. Plenty of digital receivers should be in the shops, and pay TV services, both satellite and terrestrial, will be wooing hesitant viewers with special incentives. Most other countries in Europe are also getting ready to launch DTTV services. The author discusses the phase out of analog services, digital video broadcasting standards, data rates, encryption standard, and competing digital services     

广播电视有线网络频谱资源及优化分析

首先分析了广电运营商完成前期双向网络整转后,包括模拟音频广播、模拟电视节目、数字音频广播、高标清电视节目、双向互动及宽带数据业务在内的频率规划方案;其次分析了网络传输、用户接入、视频编解码等关键技术和业务承载的发展方向;最后提出全数字化后广播电视网络频率划分建议.     

基于DTMB的多屏互动业务技术模式探析

地面无线广播技术一直是广播电视传输覆盖、实施公共服务的主要手段之一,面对智能终端的快速普及,本文提出了一种基于地面数字电视广播的多屏互动业务技术模式,能够充分利用现有宝贵的无线频率资源,实现视频服务由面向电视机或接收机单一终端到面向电视机、笔记本电脑、平板电脑、智能手机等多终端的扩展,实现地面数字电视广播的跨屏融合应用。     

Obtaining higher resolution in Asia

Important advances in digital signal processing for HDTV have occurred in Asia. This article outlines these advances, including trends in standard resolution television (STV) and progress in superhigh definition (SHD) imaging. Video coding, video recording, SHD image processing, and digital satellite broadcasting are covered, and trends in digital satellite TV and the challenges facing successful implementation of the technology are presented, as well as future research and development targets for HDTV     

ASTRA Digital Radio: high‐quality digital audio transmissions via satellite

ASTRA Digital Radio (ADR) is a satellite audio transmission technology which has been designed to be compatible with analogue radio and television transmissions via satellite. It uses QPSK modulated subcarriers above the video spectrum. For source coding, the internationally standardized MPEG 1 Layer II digital audio compression has been selected. Owing to its backward compatibility with the existing analogue audio transmission technology, ADR provides a maximum operational flexibility for both the broadcasters and the satellite operator. For the consumer this technology allows for a very high number of near CD quality radio programmes which may be received with a low‐cost receiver connected to a standard 60 cm satellite reception antenna. ADR was officially launched in August 1995 during the Internationale Funkausstellung in Berlin and currently allows for the reception of over 85 radio programmes in digital quality. Copyright © 2000 John Wiley & Sons, Ltd.     

数字卫星电视接收天线仰角方位角极化角调试探讨

数字电视正以迅猛之势发展,目前数字电视信号主要是通过卫星传输,数字卫星电视信号的接收方法与模拟卫星电视信号的接收方法相同,利用室外抛物面状天线将数字卫星电视信号——电磁波接收下来,但由于数字电视信号的特点,接收数字电视卫星信号时的“寻星”过程远比接收模拟卫星电视信号困难得多,为此对数字卫星电视接收天线仰角、方位角、极化角的调试进行探讨。     

Coded channels. Digital television by satellite

Digital compression techniques will allow satellite TV broadcasting to continue to compete effectively with broadband cable. Instead of transmitting a continuously varying analogue electrical voltage to represent the picture, digital television converts each of the pixels that makes up a TV picture into a coded message. Provided that a receiver can decode the digital message, it can build up a completely new picture, dot by dot, on the screen, with perfect results. As digital compression of television signals becomes the norm, and broadcasters try to squeeze ten or more, services down the same bandwidth that used to carry just one analogue picture, lessons will be learned-about what is acceptable on different types of picture material. Variable rates of compression could perhaps be applied to different scenes in real time, and the channel bandwidth provided for each programme being transmitted over a satellite transponder could be varied dynamically according to the data rate that each scene requires. The author discusses these various aspects of data compression and channel coding     

Time-multiplexed video transmission system: a bandwidth efficienttechnique for high-quality television transmission via satellite

A bandwidth-efficient television transmission technique called time-multiplexed video transmission (TMVT) is described. The TMVT system uses a two-dimensional filtering and interpolation technique to reduce the transmission bandwidth of TV signals, thereby increasing the utilization efficiency of a satellite transponder by approximately 50%. The system adopts the time-multiplexed component transmission scheme with a single carrier to eliminate interference between different TV signals transmitted through the same satellite transponder, and to avoid the intermodulation between the multiple FM carriers, as in the conventional frequency division multiplexing (FDM) approach. A prototype hardware system has been built and tested, with results closely matching the theoretical analysis     

Measurement of the required cross-polar protection ratio in G-PALTV FM satellite transmissions planning

A measurement campaign using live TV broadcast satellite signals and receiving commercial equipment has been carried out to study the required cross-polar protection ratio at the receiving antenna in satellite transmission planning. This experiment provides useful and realistic conclusions for the optimum spectrum allocation of TV channels in broadcasting satellite systems, as for example, the frequency offset required between cross-polar channels depending on the cross-polar rejection at the receiving antenna, for a certain grade of video signal impairment due to the cross-polar channel interference effects, and taken also into account the noise contribution on the signal     

数字电视数字广播技术与传输标准探析

当前数字电视数字广播技术为我国电子技术领域带来了新的影响,为模拟信号向数字信号转换提供技术支持。使用数字电视技术对信号进行处理与分析,有效保证了数字信号传输的安全性。根据数字电视数字广播传输的标准需求,并结合国家标准的系统框架处理流程,对关键技术的细节进行研究,并对数字电视数字广播传输的相关问题进行探析。     

数字电视多业务传输平台设计与实现

针对交互电视点播业务在广播电视领域里的快速推进,从组网技术的选择、网络结构、业务规划、保护方式等角度,全面介绍利用弹性分组环(RPR)技术建设数字电视多业务传输平台的设计方案,并通过案例证明了该技术方案能适应直播电视和交互电视传输需求,为广电行业组建数字电视SDH传输网络提供参考。     

Multimedia services and data broadcasting via satellite

Since 1995 EUTELSAT, as well as other service providers (in Europe and worldwide), in collaboration with industrial partners and research institutions have been developing digital platforms for providing multimedia services as well as data broadcasting via satellite services. These digital platforms are based on the same technologies as those used for the emerging digital television and radio services, namely Digital Video Broadcasting (DVB) and MPEG-2. These platforms will greatly improve the speed of multimedia services to the end user (e.g. up to 2 Mbit/s per session on an Internet connection) and will provide the possibility of downloading very large files in a very short time (e.g. downloading speeds of up to 40 Mbit/s per transponder) to a very large number of customers. By using the same technology as for digital television and radio, large economies of scale are foreseen, thus making these digital platforms very affordable on both the unlink side and the receiver side (e.g. less than $300 for the DVB-PC card kit)     

闭路电视频道的选择

随着我国卫星广播电视事业的发展,电视节目越来越多。本文就全频道CATV系统中如何选择相容的闭路电视频道进行了探讨,并介绍了如何用袖珍计算机进行辅助设计问题。     

Broadcasting by satellites

As a result of recent advances in signal processing technology and standards for video compression systems there has been a dramatic increase in interest in commercial applications. This paper reviews the current broadcasting situation from a number of viewpoints relevant to the future development of the available technologies. After a review of the context, which includes alternative new broadcasting technologies as well as alternative media capable of competing with satellite, digital technology is given a wide ranging assessment with particular attention paid to the direct broadcasting to the home by satellite application currently receiving considerable attention world-wide. The possible system architectures and subsystem design features are highlighted with the European Baseline Satellite Broadcasting specification developed by the European Digital Video Broadcasting Project gaining special attention. For completeness a brief review of the digital audio broadcasting system (DAB) is also given. In addition to the applications for direct broadcasting, applications in the professional domain for distributing television signals from studios to terrestrial transmitters, satellite up-link sites or cable heads or for satellite news gathering (SNG) are examined. Features of existing commercially available hardware to support these services are described briefly.     

A mixed satellite TV channel transmission scheme to enhance frequency bandwidth utilization

In the recent past, television (TV) industry has started to provide users with ultra high definition (ultra‐HD) and/or 3‐dimensional TV programs, which on the one hand, can bring users greatly enhanced viewing experience, while on the other hand, considerably increases the transmission bandwidth requirements and may lead to bandwidth shortage situations in many different types of TV systems. In particular, this bandwidth shortage poses a serious challenge in the current satellite TV broadcasting systems because of the strictly limited bandwidth available in C and Ku frequency bands. Aiming at mitigating the bandwidth shortage problem, this paper proposes an innovative mixed channel transmission scheme for the next generation satellite TV systems. The proposed scheme integrates the merits of using both broadcast and multicast methods, both Ku and Ka frequency bands, as well as both wide‐shaped and spot antenna beam types. According to the conducted comprehensive simulation experiments, this mixed scheme is able to effectively enhance the frequency bandwidth utilization with still providing users affordable quality of experience. Moreover, to cope with the impact brought by ever increasing number of provided TV channels, this paper enhances the proposed scheme by using multicast method to transmit those least popular global channels, which can efficiently reduce the quality of experience degradation up to 90% in Ku‐ and Ka‐band frequency resource restricted scenarios.