日本高清晰度电视MUSE制的频带压缩技术

本文叙述了可在单一卫星通道内传送的日本HDTV传输体制MUSE的频带压缩技术。它利用人眼的视觉特性,采用多重亚奈取样方式,将信号基带降低到8.1MHz。     

Sound Transmission for HDTV Using Baseband Multiplexing into MUSE Video Signal

A coding system developed for sound transmission accompanying the MUSE system HDTV picture is described.     

An HDTV Broadcasting System Utilizing a Bandwidth Compression Technique?MUSE

An HDTV broadcasting service on one satellite broadcast channel became available after the development of a transmission system called MUSE involving bandwidth compression. Using MUSE, a satellite channel of width 27 or 24 MHz in the 12 GHz band can carry an HDTV picture, digitally-coded four-channel sound and independent digital signal at about 100 Kb/s.     

HDTV多媒体大屏幕显示墙系统方案

介绍了高清晰度多媒体大屏幕显示墙系统的原理、方案、组成及关键技术,并分析了它的应用前景.     

HDTV多媒体大屏幕显示墙中制式变换的研究

本文介绍了HDTV多媒体大屏幕显示墙系统的组成及应用前景．重点阐述了HDTV分割器中制式变换的问题和制式变换的基本原理及解决方法。     

HDTV的关键技术

本文讨论高清晰度电视（ＨＤＴＶ）体制的关键技术。本文分析表明，ＨＤＴＶ的关键技术主要包括信源压缩编码、信道编码技术及传输调制技术，而传输调制方式则是ＨＤＴＶ体制的核心内容。     

A coding and Modulation scheme for HDTV services in DMB-T

In this paper a channel coding and modulation scheme for providing HDTV broadcasting services is presented, which adopts BICM structure as inner code in connection with 64QAM constellation and OFDM transmission. A new mapping method is designed to maximize the minimum Euclidean distance between signal points divided by feedback bits, thus an iterative algorithm between demodulator and decoder can be performed to acquire performance improvement. Analysis, simulation and laboratory test results have proved that the proposed system has good SNR performance in both AWGN and multipath channels.     

The HDTV Grand Alliance system

The Grand Alliance (GA) was formed to define and construct a system for the delivery of HDTV using terrestrial broadcast channels. This system is composed of the best components from previously competing systems considered by the FCC. MPEG-2 syntax is used with novel encoding techniques to deliver a set of video scanning formats for a variety of applications. The paper focuses on video compression technology and also describes the important features and concepts embodied in the GA system as compared to the previous digital HDTV systems     

Digital HDTV broadcasting over the CATV distribution system

This contribution deals with the digital broadcasting of HDTV channels over the cable television (CATV) distribution system, using either single-carrier QAM or an orthogonal frequency division multiplex (OFDM) of many QAM carriers to represent an HDTV channel. Assuming that no error-correcting codes are used, we investigate two distinct cases: in the first case, a few HDTV channels are transmitted among many analog TV channels, whereas in the second case all transmitted channels are HDTV channels. We show that in the first case the transmit power of an HDTV channel can be substantially reduced (by about 10 dB or more) as compared to the transmit power of an analog TV channel, while still maintaining a satisfactory bit error rate (BER). In the second case, not only a considerable reduction of the total transmit power but also a reduction of amplifier cost and an increase of the number of TV channels can be achieved. Single-carrier QAM is found to perform slightly better (at most about 1 or 2 dB) than a multi-carrier QAM.     

转播用DWDM高清晰度电视传输系统

1前言日本已拟定于2000年开始进行以数字高清晰度电视和多媒体数据业务为中心的BS（广播卫星）数字广播。为此,除了BS数字广播的各类播出设备需作好充分准备之外,日本广播协会（NHK）正大力推进成为普及Hi-Vision节目制作关键的新闻中心、演播室等以及现场节目制作、转播用的各种必需器材设备的开发研制。作为BS数字广播系统的组成部分,日本广播协会技术局和广播技术研究所开发研制了DWDM（密集波分复用）高清晰度电视传输系统。采用这一系统,多信道Hi·VisionSDI（串行数字接口）信号,用1根光纤即可进行传输。本文拟对DWDM…     

嵌入式操作系统在HDTV机顶盒中的应用

介绍一个高清晰度电视机顶盒方案中软件系统的系统结构，阐述了机顶盒软件中使用的嵌入式操作系统STLite/OS20的原理及其特点，并举例说明了这个嵌入式操作系统在机顶盒系统中的使用。     

加快我国高清电视、数字电影和移动多媒体广播电视发展——国家广电总张海涛副长在BIRTV2008主题报告会上的讲话摘要

我国已建成世界上覆盖人口最多,无线、有线、卫星、互联网等多种技术手段并用,中央与地方、城市与农村、国内与国外并重的规模庞大的广播影视网络.如何保证全系统安全运行,如何完善广播影视公共服务体系,如何尽快实现数字化转换,构建传输快捷、覆盖广泛,技术先进的广播影视传播体系,是我们全国广电系统当前和今后一段时期的重要任务和神圣使命.     

Multimedia services over digital subscriber lines

We study the problem of reliable and yet efficient multimedia communications over asymmetric digital subscriber line (ADSL) through joint consideration of compression/coding and channel transmission techniques. The transmission of digital multimedia data requires the existing systems to be augmented with functions that can handle not only ordinary (nonmultimedia) data. In addition, the high volume of multimedia data can be handled efficiently only if all available system resources are carefully optimized. We consider the special characteristics of ADSL channels to formulate optimization criteria. We present a system where the encoder consists of a layer coder that divides and compresses the source data into coded layers of multimedia data with different performance and quality-of-service requirements. The encoded bit streams are then transmitted over a noisy channel, where channel noise may distort the data. The decoder removes all the coding and compression applied in the encoder to obtain as close as possible the original data. It is conceivable that for such a system the loss of information occurs not only during the source compression but also in the channel transmission. The source coding scheme and bit stream arrangement have a direct impact on the channel distortion. Therefore, the joint consideration of source/channel coding design is ideal to reduce the overall information loss     

Multimedia services interoperability in next-generation networks for the residential environment

This article presents an open and functional architecture based on a next-generation network solution in order to seize its converged nature to guarantee interoperability among different platforms and terminals. The defined architecture is an integrated solution for end-to-end communication of various IP multimedia subsystem platforms marketed by different vendors, belonging to several operators located in different countries across Europe and supporting multiple terminals and technologies in order to experiment with a new broadband telephony service for the residential environment. This work addresses, in particular, the interoperability problems of name resolution and implementation of the Session Initiation Protocol Interface at the terminal as a key use in such a scenario. Also, several advanced services are developed and tested within the proposed architecture as a proof of concept of the IMS capability for quick service creation and deployment. The architecture proposed contributes to the reduction of obstacles and barriers among the European countries in order to adopt NGN architectures, allowing a new type of communication that is more complete and flexible.     

The Grand Alliance system for US HDTV

The US HDTV process has fostered substantial research and development activity over the last several years. The Advisory Committee on Advanced Television Service (ACATS) was formed to advise the FCC on the technology and systems suitable for delivery of high definition service over terrestrial broadcast channels. Four digital HDTV systems where tested at the Advanced Television Testing Center. All the systems gave excellent performance, but the results were inconclusive and a plan for a second round of tests was prepared. As each of the four systems where being readied for retest. The proponents of the four individual digital HDTV proposals worked together to define a single HDTV system which incorporated the best technology from the individual systems. The consortium of companies, called the Grand Alliance (GA), announced a combined system and submitted it to ACATS for consideration. After ACATS certification, the GA began construction of a prototype system to submit for laboratory testing at the end of 1994. This paper describes the video compression subsystem and the hardware prototype. The preprocessing, motion estimation, quantization, and rate control subsystems are described. The system uses bidirectional motion compensation, discrete cosine transform, quantization and Huffman coding. The resulting bitstream is input into a transport system which uses fixed length packets. The multiplex transport stream is input into the 8-VSB transmission system. Finally, the specifics of the hardware implementation are described and some simulation results are presented     

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)     

Choosing an American digital HDTV terrestrial broadcasting system

A public process has been in place in the United States for six years to establish an HDTV terrestrial broadcasting standard. The process, having moved through a planning phase, a competition phase, and an examination phase, has now entered a cooperation phase. Remarkable progress has been made-a testament to the process. During 1994 the American digital HDTV terrestrial broadcasting system will be tested, fully documented, and recommended to the FCC for adoption     

HDTV码流输出系统的研制

提出了将ＨＤＴＶ软件编码数据流转换成串行码流的方案并研制了相应的转换,输出系统。系统基于通用微机,将非实时软件编码的ＨＤＴＶ视频或舆流数据转换成串行码流,并提供时钟同步或包同步信号,其码流类别,编码系数,码率,工作方式等可选,它的研制成功在目前尚无ＨＤＴＶ编码芯片的情况下,得以为ＨＤＴＶ制式研究,设备或系统的研制或测试等,灵活,方便地提供信号。     

Advanced digital HDTV transmission system for terrestrial videosimulcasting

Transmission aspects of the advanced digital high definition television (AD-HDTV) system, for terrestrial simulcast delivery of HDTV are described. In AD-HDTV, two quadrature-amplitude-modulated (QAM) carriers, with different power spectral densities, are employed in a frequency division multiplex (FDM) mode within the standard 6-MHz channel. The resulting spectral shaping allows a larger power to be transmitted, compared to that for a single QAM carrier, for the same level of perceptual interference into cochannel NTSC. The coded video data are split into high-priority (HP) data and standard-priority (SP) data, and the vital information is sent on the appropriate QAM carrier, resulting in a robust audio and video transmission system. The availability is higher in scenarios where the carrier-to-noise ratio (CNR) is above the threshold for HP reception but below the threshold for SP reception; this is important in fringe areas. The NTSC planning factors, suitably modified for HDTV delivery, are used to estimate the coverage area for AD-HDTV. The calculated AD-HDTV coverage area of 54.5 miles is comparable to that for NTSC transmission