Performance of multimedia broadcasting through ISDB transmissionsystem

Multimedia broadcasting has the benefits of versatile information representation, intelligent viewing environments, and economical systems. Integrated Services Digital Broadcasting (ISDB) presents a concept for future digital broadcasting systems. Full-scale multimedia broadcasting services can be realized by ISDB. There are two aspects in multimedia broadcasting from the viewpoint of ISDB. One is “transmission multimedia” and another is “presentation multimedia”. The former means that ISDB provides services by exploiting the characteristics of various types of broadcast channels. It also integrates all broadcast networks and is interoperable with communications and package media. The latter means that ISDB can flexibly combine and send various types of representation media that most appropriately convey the information. Multimedia broadcasting by ISDB is expected to achieve interactive viewing and to raise individual viewer satisfaction. ISDB will also make it possible to set up multiple small-scale broadcast stations and to provide a many-to-many information linking environment for transmitting information between an unspecified number of individuals     

Reflective SOA-Based Bidirectional WDM-PON Sharing Optical Source for Up/Downlink Data and Broadcasting Transmission

We proposed and experimentally demonstrated the reflective semiconductor optical amplifier (RSOA)-based wavelength-division-multiplexed passive optical network (WDM-PON) scheme where not only up/downlink data services but also broadcasting service could be provided using a single optical source. In the proposed scheme, the digital signal and subcarrier multiplexing (SCM) signal for downstream were simultaneously modulated by a single distributed feedback laser diode and RSOA in optical network unit remodulated downstream source as an upstream. Without performance deterioration of digital signals both in up- and downstream, the proposed WDM-PON scheme can stably offer the SCM signal for broadcasting service. In the experiment, 1-Gb/s digital signals both for up- and downstream and 20-Mb/s SCM signal at 2.2 GHz for broadcasting were demonstrated in 10-km bidirectional link     

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)     

OFDM for broadcasting in presence of analogue co-channelinterference

This paper treats the problems of digital TV terrestrial broadcasting in presence of co-channel interference from analogue TV services. The channel capacity is calculated for the optimum distribution of the transmitted power. An OFDM scheme is presented which is designed to be robust to the analogue TV interference. Power and number of bits per symbol are assigned to each OFDM channel to give the maximum data rate for a given signal to interference ratio. Simulations of the proposed scheme, for 8 MHz bandwidth and interference from a system G PAL signal, show that acceptable error rate can be achieved for e.g. 27 Mbit/s and 39 Mbit/s at signal to interference ratios of -6 dB and 0 dB, respectively. The proposed scheme is suitable for the next generation terrestrial TV networks which are going to coexist with the current analogue systems     

DVB-T和ISDB-T的比较及统一化传输方案

比较DVB-T和ISDB-T的信道编码方案，提出一种统一的称之为非均匀频带分割传输正交频分多路复用（NBST-OFDM）的数字电视地面广播系统的传输方案，DVB-T和LSDF-T均可视为该方案的特例。     

Interactivity in broadcasting and its application to ISDB services

Given that broadcasting is generally characterized by real-time one-way transmission, it is an essential task for this medium to provide interactivity developed in the fields of telecommunications and computers when introducing multimedia into a broadcasting system. This paper discusses how to use and implement interactivity in broadcasting services. It further discusses what functions are required for introducing interactivity into broadcasting. The practicality of interactive services in one-way broadcasting transmission is clarified. A simulation system of ISDB services to evaluate viewers' human interface was developed. The results of experiments using the simulation system are also discussed. It is shown that user-friendly ISDB services can be achieved     

用声表面波滤波器实现高速光纤传输系统的定时恢复

在高速光纤数字传输系统中,尤其在长中继链路系统中,定时恢复的质量直接影响到传输系统的性能。本文分析了100Mbit/s以上光纤数字传输系统用声表面波滤波器(SAW—F)定时提取电路。首先给出SAW—F的基本原理;然后讨论了SAW—F定时提取实现方案并分析了其抖动积累特性,得出SAW—F定时提取电路的设计依据;最后,根据理论分析的结果,我们设计了一个可用于155.520Mbit/s光纤数字传输系统的SAW—F定时提取电路。分析和实验表明,SAW-F适合用作100Mbit/s以上数字传输系统的定时提取。     

A flexible transmission technique for the satellite ISDB system

A new transmission technique which can achieve suitable quality and reliability for satellite ISDB (Integrated Services Digital Broadcasting) is introduced. The transmission system for satellite ISDB must have high spectrum efficiency, continuous service availability and also superior flexibility in its transmission scheme. This paper first studies appropriate transmission schemes, taking account of the 12 GHz band DBS (direct broadcasting satellite) system. Then, employing a hierarchical transmission technique and a newly proposed TMCC (transmission and multiplexing configuration control) signal, it describes the requirements for satellite ISDB. The hierarchical transmission extends the service availability under heavy rainfall conditions. The TMCC signal can change the transmission configuration depending on the program content and the weather conditions. In addition, a generalized method for the design of transmission configurations for satellite ISDB is presented     

声音和电视广播新技术

本文就４个方面介绍了声音和电视广播新技术：１现行声音和电视广播的功能增强和性能改进；２数字技术在声音和电视广播中的应用；３卫星广播和节目传送；４ＰＣ机应用，多媒体和ＩＳＤＢ。     

The European system for digital multi-programme television bysatellite

The general concepts of the system for digital television transmission by satellite developed within the European DVB (digital video broadcasting) project and standardised by ETSI (European Telecommunications Standards Institute) are described. The system, named DVB-S, is intended to provide DTH (direct-to-home) multi-programme TV services in the BSS (broadcasting satellite service) and FSS (fixed satellite service) bands and is addressed to consumer IRDs (integrated receiver decoders), as well as collective antenna systems (SMATV, satellite master antenna TV) and cable television head-end stations, with a likelihood of remodulation. 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. For example, in climatic zone E (in Europe) on a 33 MHz transponder a data-rate of 38.1 Mbit/s can be transmitted, adequate to provide five standard definition TV programmes (SDTV) or, alternatively three to four enhanced definition programmes (EDTV), while ensuring 99.90% service availability (in the average year) with 50-cm receiving antenna within the 51 dBW EIRP (equivalent isotropic radiated power) service area contour     

高清晰度电视（HDTV）的压缩编码

本文简述HDTV压缩编码的发展;介绍HDTV的140兆比特/秒传输,数字/模拟混合型HDTV卫星广播,以及全数字HDTV地面广播中采用的图像压缩编码原理;并简要展望其发展前景。     

Digital visions: where the superhighway will lead

The author looks forward to the world of interactivity made possible entirely by digital communications, storage and compression. Digital technology has also expanded the capacity of communications networks, supporting an enormous rate of growth in traffic. Compression has immediate transmission cost benefits for satellite broadcasters, since an analogue PAL transponder covering Europe, say, may cost £4 million per year. A compressed 8 Mbit/s digital service (Filmnet), with four digital channels per transponder, quarters the cost per programme service. For a 2 Mbit/s digital service, costs could fall to around £250 000 per year. As the cost of compression equipment falls, many more services can be delivered direct to homes by satellite or cable systems     

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.     

Optical Pulse Formats for Fiber Optic Digital Communications

Some new optical pulse formats are investigated for solving practical problems in fiber optic communication systems. These pulse formats provide many advantageous features such as error monitoring capability, abundant timing information, uniform optical power utilization, stable detection of optical input, and so forth. It is shown that a modification of Personick's receiver design theory can be used for comparison of various optical pulse formats. The comparison suggests that for state-of-the-art fiber systems with moderate fiber loss and moderate repeater spacing, where no pulse equalization is required, some new classes of 1 binary digit converted to 2 binary digits (1B2B) or 2B3B formats will permit the realization of very simple and reliable repeaters for fiber optic digital transmission. A future low-loss fiber system may permit a very long repeater spacing with the help of equalization. In this case, application of the correlative signal-processing technique is shown to be very promising. Experimental 6.3 Mbit/s and 100 Mbit/s transmissions demonstrate some advantageous features of these optical pulse formats.     

An optical bit-rate flexible transmission system with 5-Tb/s-kmcapacity employing multiple in-line erbium-doped fiber amplifiers

An optical bit-rate flexible transmission system using erbium-doped fiber amplifiers (EDFAs) is proposed, and the system design is discussed. An optical bit-rate flexible system using multiple in-line erbium-doped fiber amplifiers has produced a regenerative repeater spacing of 505 km at 10 Gb/s and 523 km at 5 Gb/s for direct-detection systems. This system proves that an optical bit-rate flexible system with a transmission capacity of 5.05 Tb/s-km can be feasibly constructed. System capacity is clarified both theoretically and experimentally. The power penalties involved are discussed. The related optical and electrical circuits proved operational above 10 Gb/s. The 523 km at 5 Gb/s and 505 km at 10 Gb/s transmission experiments successfully demonstrated that EDFAs effectively enhance a system's transmission capacity     

400 Mbit/s Optical Regenerator Integrated Circuits

This paper discusses 400 Mbit/s optical regenerator integrated circuits, focusing on their circuit architecture and performance, and describes their application to a 400 Mbit/s optical regenerator. The basic design concepts for high-speed regenerator IC's are discussed and a new integrated circuit architecture based on these design concepts is proposed. The proposed architecture of regenerator IC's is used to fabricate five IC chips (Reshaping IC, Retiming IC, Decision IC, LD driver IC, and dc-to-dc converter IC) using a high-speed bipolar process with transistors having a unity gain bandwidth of 5 GHz. The combination of these IC's can achieve submarine and terrestrial long-haul optical transmission at bit rates up to 450 Mbits/s. These IC's are applied to a 400 Mbit/s IC optical regenerator. Experimental results show that the IC optical regenerator has an optical dynamic range of more than 27 dB without any adjustment and received average optical power required to maintain a 10^-11error rate is less than -38 dBm. Experimental results fully satisfy the system requirements, and the feasibility of commercial application is demonstrated.     

Performance evaluation of 2.5 Gbit/s and 5 Gbit/s optical wireless systems employing a two dimensional adaptive beam clustering method and imaging diversity detection

Previous indoor mobile optical wireless systems operated typically at 30 Mbit/s to 100 Mbit/s and here we report on systems that operate at 2.5 Gbit/s and 5 Gbit/s. We are able to achieve these improvements through the introduction of three new approaches: transmit beam power adaptation, a two dimensional beam clustering method (2DBCM), and diversity imaging. Through channel and noise modeling we evaluated the performance of our systems. The performance of a novel optical wireless (OW) configuration that employs a two dimensional adaptive beam clustering method (2DABCM) in conjunction with imaging diversity receivers is evaluated under multipath dispersion and background noise (BN) impairments. The new proposed system (2DABCM transmitter with imaging diversity receiver) can help reduce the effect of intersymbol interference and improve the signal-to-noise ratio (SNR) even at high bit rate. At a bit rate of 30 Mbit/s, previous work has shown that imaging conventional diffuse systems (CDS) with maximal ratio combining (MRC) offer 22 dB better SNR than the non-imaging CDS. Our results indicate that the 2DABCM system with an imaging diversity receiver provides an SNR improvement of 45 dB over the imaging CDS with MRC when both operate at 30 Mbit/s. In the CDS system, an increase in bandwidth from 38 MHz (non-imaging CDS) to 200 MHz approximately, is achieved when an imaging receiver is implemented. Furthermore, the three new methods introduced increase the bandwidth from 38 MHz to 5.56 GHz. At the least successful receiver locations, our 2.5 Gbit/s and 5 Gbit/s imaging 2DABCM systems with MRC offer significant SNR improvements, almost 26 dB and 19 dB respectively over the non-imaging CDS that operates at 30 Mbit/s.     

Optical Fiber System Applications Aspects in Future NTT Networks

This paper describes some aspects of optical fiber cable system applications in future NTT transmission networks, considering voice transmission as predominant even in future transmission networks in accordance with demand forecasts. The desirable optical fiber cable transmission system which should be developed and introduced is discussed taking into account optical fiber costs, demand estimates, pertinent technological developments, etc. It was concluded that the following process of introducing optical fiber cable transmission systems should be feasible. In the first step, approximately 32 Mbit/s and 100 Mbit/s digital transmission systems should be employed for short and medium haul trunks with heavy traffic using graded index optical fibers. A large capacity, long haul digital transmission system, such as a 400 Mbit/s system using graded index or, if possible, single mode optical fiber should be introduced next. The optical fiber cable costs at which fiber systems become economical, depend upon the application area. For short and medium haul systems, 40¢ per meter per core is required, but $2 per meter per core is sufficient for large capacity, long haul systems. For a short haul system operating at approximately 1.5 Mbits/s or 6 Mbits/s, the advantages of its introduction greatly depend on optical fiber costs which should be less than 20¢per meter per core.     

光纤传输在各种通信和广播网中的应用

本文阐述光纤传输系统在公用通信－宽带综合业务数字网（Ｂ—ＩＳＤＮ），在专用通信－局域网与城域网（ＬＡＮ／ＭＡＮ），在有线电视广播网（ＣＡＴＶ）以及在移动通信蜂窝网（ｃｅｌｌｕｌａｒ）等各种通信网和广播网中的应用，并介绍它们的特点、相互差异，以及发展趋向。