Present Trends in High-Speed and Broad-Band Communications Services in Japan

This paper describes present trends in high-speed and broad-band communications services in Japan. It gives an overview of video, high-speed digital leased circuit and satellite digital communications services, and gives examples of their applications. Recent trends in telecommunication services and technology are described, including video conferencing services presently available in more than ten cities throughout Japan, as well as a video response system which is about to be put into service. It also describes the present status of Japan's cable television (CATV) system and discusses its future development. Finally, NTT's plans for high-speed and broad-band communications service in the future are previewed.     

A Transmission Scheme for Integrated Services on Broad-Band Internal Private Business Networks

Internal business networks are expected to present an economic area of application for broad-band communications. A star network with switches optimized for various services is envisaged. An asynchronous switch for video in square wave frequency modulation (SWFM) format can provide a practical solution for full bandwidth switched video services. A transmission scheme is described which combines a SWFM video service together with synchronous PCM data and voice services, asynchronous data up to 9.6 kbauds and network clocks at both 2 MHz and 160 kHz for ISDN, so that all services destined for one terminal site may be transmitted in binary format on cable or fiber. An experimental link is described which provides up to 10 Mbit/s data capacity together with the video service. The hardware is constructed with 74HC family CMOS. An analysis of the effects of data modulation on video quality is given. Measurements of video S/N and distortion are reported. Measured bit-error rate in a 64 kbit/s data channel is reported. The measurements relate to a coaxial cable link with link lengths from 200 to 400 meters.     

Multimedia Stream Binding for a Pan-European Services Platform

The ability to carry stream information over a range of network types in a managed way will become an essential requirement for telecommunications network operators as future services evolve to include the transmission of audio/video and bulk data streams. This paper details the architecture of a working pan-European demonstrator offering multimedia services through the integration of stream control, as specified in the Object Management Group's (OMG's) control and management of audio/video streams, with a TINA-compliant service management environment. This CORBA-based demonstrator, known as the EURESCOM services platform (ESP), has been developed by six European telecommunications companies within EURESCOM project P715. Various modelling concepts, as defined by TINA, ODP and OMG, have been used and verified in a first prototype implementation, with connectivity provided by commercially available multimedia technology such as H.320/323 products. This EURESCOM services platform prototype is one of the first demonstrators world-wide to implement OMG's control and management of audio/video streams specification.     

Millimeter waves for short-range multimedia communication systems

A framework for the performance characterization of short-range communications systems is developed with the intention of investigating the feasibility of new multimedia wireless services at millimeter waves (MMWs). Both narrow- and wide-band systems are considered for mobile and/or fixed users. This paper aims at defining and evaluating proper metrics to characterize the service quality for the user and jointly takes the propagation characteristics, the transmission techniques, and the multiple access protocols into account. The definition of service-oriented metrics is emphasized. Three different real scenarios operating at MMW are investigated with a unified perspective: intelligent transport systems, wide-band local-area networks, and local multipoint distribution systems for interactive video services. The role played by the MMW band in the development of these services is discussed. In each scenario, accurate propagation analysis is carried out and suitable countermeasure techniques are pointed out in order to join suitable service-quality levels. The methodology considered is based on both analytical and semianalytical tools for performance evaluation     

Broadband ISDN Switching Capabilities from a Services Perspective

Broadband switching and transmission technologies are maturing rapidly, promising to make broadband ISDN (B-ISDN) possible and potentially economical in the near future. The diversity of possible B-ISDN services provides much impetus for the implementation of B-ISDN, but complicates the task of specifying network switching requirements. This paper examines a few representative services in order to generate a set of basis vectors in capability space. New services are then projected onto this basis; if a new service cannot be constructed from the basis vectors, other vectors are added to the basis set. B-ISDN architects can then specify switching requirements by selecting those capability basis vectors that are required for the services most in demand. For full motion entertainment video services, circuit switching capability at about 150 Mbit/s may be required, while selective broadcast and remote switching capabilities may reduce the cost of these services. For subvideo-rate services, new transfer mode (NTM) capability may be required to allow users the flexibility to allocate access channels dynamically on a per-call basis. Multiple connection (e.g., voice and video) and multiple party call capabilities may be required for many B-ISDN services, implying a need to extend the ISDN signaling protocol. The capability for the user to request network code conversion between different coding formats (e.g., NTSC or HDTV), and network compression of signals to reduce the cost of interoffice facilities, may also be required. Finally, fast call setup capability and high calling volume capabilities may be required, implying a need to distribute call processing functions over multiple processors in the central office.     

Combined Connection Admission Control and Packet Transmission Scheduling for Mobile Internet Services

Mobile Internet access is expected to be the most popular communication service in the near future. In this paper, we investigate radio resource management for mobile Internet multimedia systems that use the orthogonal frequency division multiple access and adopt the adaptive modulation and coding technique. It is assumed that real-time (RT) service such as streaming video and best-effort (BE) services such as file transfer protocol and hypertext transfer protocol coexist in the systems. We suggest two levels of radio resource management schemes: the connection admission control (CAC) scheme at the first level and the packet transmission scheduler at the second level. The proposed scheduler does not assign higher priority to RT packets over BE packets unconditionally. Instead, only the RT packets that are close to the deadline are given higher priority. Therefore, the performance of BE services is improved at the cost of RT services. To control the performance degradation in RT services within an acceptable level, the CAC algorithm functions as a congestion controller. The combined effects of the proposed CAC and packet scheduling by using the cross-layer simulation that covers from the physical layer to the Internet application layer are evaluated. The numerical results show that the proposed schemes greatly improve the performance of BE services while maintaining the quality of video service at an acceptable level.     

Applications of Future Braod-Band Services in the Office and Home

The demand for broad-band services in connection with numerous applications in the business and private sectors will be economically met in the future by the broad-band ISDN, the internationally standardized universal network for all services. Broad-band services and their applications can be roughly divided into four types of communication. The "dialogue" services include video telephony, video conferencing, and high-speed document and data transmission. "Retrieval" services cover film retrieval, broad-band videotex, document retrieval, high-definition image retrieval, and retrieval of graphics, text, and data. One representative of "access" services is cabletext. Of the "distribution" services, television is the most prominent. The demand for broad-band services in the office will depend primarily upon cost-effectiveness, and in the home will depend primarily upon anticipated benefits, cost, available purchasing power, and leisure time. In either case, prestige considerations may also play a part. The sine qua non for the fast spread of new broad-band services will at all events be-in addition to acceptable terminal equipment-low user charges.     

IPTV业务监测技术方案

IPTV业务的发展要求必须对网络传输质量和传输内容进行监测。文章提出了一种IPTV监测网络系统结构,从监测网络的物理结构和逻辑功能两个方面对IPTV业务监测技术方案进行了设计,并详细介绍了IPTV监测网络的功能,对未来IPTV监测系统的实施提供了思路。     

Visual Hysteresis Based Dynamic Interference Shaping for Real-Time Video Services in Dense Deployed Cellular Networks

Due to the dense deployed base stations and the growing traffic of best effort (BE) services, frequent bursty interference becomes one of major challenges to assure quality of experience (QoE) for real-time video services. Considering those situations, a novel dynamic interference shaping method has been proposed in this paper, to assure the QoE for real-time video services. Firstly, to evaluate the quality impairment induced by bursty interference, we proposed a new QoE prediction model with content-adaptive and hysteresis effect. Secondly, the cellular interference traffic model is proposed in the framework of interference shaping. By this traffic model, the interference characteristic of best effort services is analyzed and the rate scaling factor (RSF) is introduced to adjust the transmission power of BE service, thus to neutralize the interference of real-time video service. Finally, the utility function with QoE for real-time video services and BE services is presented, and we utilize particle swarm optimization method to obtain the optimal RSF. Simulation results show that proposed method greatly improves QoE for real-time video services.     

二网融合的可视电话与多媒体增值业务系统

提出一种分别利用PSTN传送话音,利用Internet传送视频和提供实时广告、视频点播或直播的可视电话与多媒体增值业务系统及其实现方法,给出了通话者音、视频传送并在终端同步还原的设计要点,以及实现其他多媒体业务的设计框架。介绍了系统的运营模式及其特点。     

Home Communication Systems

New small-band and broad-band communication services will expand possible application for the user. For the benefit of these services, home communication systems are required with TV sets, video recorders, microcomputers, and telephones as key components. In the residential area a trend can be observed from single terminals for specific services towards multiservice home terminals. In-house transmission systems with future home terminals and today's development trends are described in this paper.     

Video streaming over P2P networks: Challenges and opportunities

A robust real-time video communication service over the Internet in a distributed manner is an important challenge, as it influences not only the current Internet structure but also the future Internet evolution. In this context, Peer-to-Peer (P2P) networks are playing an imperative position for providing efficient video transmission over the Internet. Recently, several P2P video transmission systems have been proposed for live video streaming services or video-on-demand services over the Internet. In this paper, we describe and discuss existing video streaming systems over P2P. Efficient (delay tolerant and intolerant) data sharing mechanisms in P2P and current video coding trends are elaborated in detail. Moreover, video streaming solutions (live and on-demand) over P2P from the perspective of tree-based and mesh-based systems are explained. Finally, the conclusion is drawn with key challenges and open issues related to video streaming over P2P.     

Multicast and Broadcast Multimedia Services in Mobile WiMAX Networks

Multicast and broadcast services in WiMAX are downlink point-to-multipoint access services optimized for transmission of a common set of multimedia data packets to a group of users. This capability enables low-cost delivery of large volumes of popular contents (e.g., for video/audio streaming and file sharing) in a mobile network. The MCBCS framework in WiMAX allows multicast/broadcast of data in a radio channel that is time shared with unicast services. In a single-frequency network, where MCBCS transmissions are synchronized or coordinated across BSs in the designated service area, the mobile stations can use macro-space diversity to improve achievable data rates and also maintain service continuity and power saving across cells with minimal interaction with the network.     

FLC-Based MBWIMA/UMTS Protocol for Multimedia Services in UTRA TDD Mode

An intelligent medium access control (MAC) protocol based on fuzzy logic control (FLC) is proposed and compared with a general packet radio system in UMTS (GPRS/UMTS), priority scheme and the movable boundary wireless integrated multiple access in UMTS (MBWIMA/UMTS) protocols. The integrated video/voice/data services of UMTS in UTRA TDD mode have different transmission properties. By fuzzy logic control, the resources of the wireless communication can be intelligent assigned for different types of mediums. The voice-video dropping probability and data packet delay are input to FLC to optimally select the maximum number of voice/video slots. Voice activity detector (VAD) and multiple access interference in single cell are also considered in the simulations.     

基于DSP的双路信道无线视频终端设计

以高性能DSP为设计核心,采用H.264编码,利用双路增强型数据业务(EDGE)信道,将视频流发送到视频服务器.提出了基于双路缓冲区判断的发送控制策略,详细描述了系统结构及软硬件设计.实验结果表明,CIF格式的图像传输基本能达到实时的要求.     

OV7670及其在3G流媒体服务中的应用

在3G网络视频监控迅速崛起的时代背景下,介绍一种CMOS图像传感器OV7670。从其基本结构、编程功能及数字图像的输出方面做了具体研究,最后给出一种OV7670在3G流媒体（视频流）服务中的应用方案,对3G无线视频传输系统设计具有指导意义。     

Packet video

The 1990s will see a large increase in the use of video for many purposes, made possible through the use of new optical storage and transmission methods, as well as radio and satellite communication. HDTV, new broadcast services and 64 kbit/s ISDN video are all at an advanced stage of development. Digital methods of transmission and storage feature prominently in future scenarios of video usage. To avoid long delays in transmission, packet video techniques for storage of high-quality material on optical discs are being considered. Coded video signals can be transmitted in packet form at variable bit rate. The author discusses the principles of packet video. Packet loss, queueing delay and layered coding are discussed. The future developments are also discussed     

Use of long-wavelength devices for analog optical-fiber loops

This paper reports on experimental investigations in the use of available long-wavelength (1.3-1.55-mum) devices in wide-band analog optical-fiber loops assumed functioning in a conventional star-configured switched network. Since for economic reasons analog TV transmission will remain attractive for the foreseeable future, the objective of this work is to extend loop length from 2 km (now feasible) to about 10 km. Distances of up to 10 km are needed to accommodate three or four television channels (each switchable) and narrow-band (NB) services. It is shown that with available "experimental" long-wavelength LED's and p-i-n photodiodes distances up to about 10 km are feasible.     

一种低噪声高增益宽带视频对数放大器

着重介绍了一种用于电子对抗系统预警雷达接收机中的低噪声高增益宽带视频对数放大器的设计原理，制造工艺及其应用，进一步考察了国内外整机系统的发展现状，综合介绍了目前国内外视频对数放大器的发展及其在整机系统中的应用前景。     

Fiber Optic Transport Systems for Present and Future Local Networks

This paper describes fiber optic transport systems for present and future local networks. The present most important fiber optic system in a local network emerges as a broad-band video distribution system, because large-scale system introduction might be attained only for distributed video services. The system architecture and system parameters are presented. As for future integrated services, a highspeed digital transmission system and local network architecture are very important. The network architecture should be constructed to meet the demands for increased flexibility, capacity, reliability, and economy. Considering expected future demands and technologies, a new fiber optic local network architecture is proposed. The architecture's main features are the use of transmission processing nodes and a multilane-ring structure in subscriber transfer networks in combination with star-shaped subscriber access lines.