Networked Broadcasting Systems

Toward Advanced Digital Broadcasting

igital broadcasting is no longer the exclusive realm of satellite, terrestrial, and cable TV networks. Diverse networks, including the Internet, and home server Yoshihiro Ddevices with large-capacity storage are expected to bring about new services FUJITA, exploiting broadcasting, communications, and storage technologies. These services will Director, allow viewers to access any program or piece of information via various transmission Networked Broadcasting media, regardless of location or time. Our "Networked Broadcasting Systems" group is Systems working toward the construction of a new broadcasting system that will greatly benefit viewers. Our work spans a range from advanced program production/transmission for broadcasting stations based on computer network technology to transmission to home networks. We will meet the challenge of such diverse research and development, which will be needed for digital television to develop into integrated services television. One area of research involves the realization of a reliable and safe broadcasting network exploiting computer network technology that is free of temporal and spatial restrictions. While signal transmissions within a broadcasting station, between broadcasting stations, and between the broadcaster and viewers have used networks designed exclusively for broadcasting purposes, new network technologies are making it possible for general-purpose networks to transmit high-quality video, such as HDTV, at high speed. Together with this research, we are going to participate in standardization activities related to network connectivity and receiving systems, which have a significant influence on ease-of-use and cost.

Broadcasting station

Internet

Cable TV network Integrated servicesservices terminal

Internet

Networked broadcasting systems research overview

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Wireless Systems

Finding New Frequency Resources and Making Good Use of Radio Technologies

he digitization of broadcasting will inevitably transform TV from a medium that is "watched" into one that is "used." The paradigm shift began with digital BS Toshihiro Tbroadcasting in December 2000 followed by digital terrestrial broadcasting, NOMOTO, which started in the three largest Japanese metropolitan areas in December 2003. Director, Expansion of digital terrestrial broadcasting is now on track to achieve a nationwide Wireless Systems service by 2011. To help digital terrestrial broadcasting spread, a broadcast-wave relay on a single frequency (Single Frequency Network) is seen as a way to make the most of the available frequencies and to reduce the costs related to service area expansion. Also anticipated is the introduction of mobile receivers for receiving data broadcasting and HDTV even on highways or on Shinkansen super-express trains. STRL's Wireless Systems department is developing the various technologies needed for the implementation of such broadcasting. Our department is also studying the feasibility of a 21-GHz-band satellite broadcasting system that could become a transmission channel for the 4000-scanning- line "Super Hi-Vision" system. In particular, transmissions on the 21-GHz band suffer from severe radio-wave attenuation, so attenuation countermeasures are being actively developed by us. We are also researching wireless studio cameras and a highly mobile relay broadcast network outside broadcasting stations. These technologies will respectively enable diversified program production and prompt emergency reporting. As part of our search for innovative ways to use new frequencies for broadcasting, we are also conducting basic research on radio-wave propagation characteristics and research that may lead to new kinds of devices. We are determined on our pursuit of new frequencies, transmission channel resource development, and more effective use of limited radio resources for expansion of broadcasting.

12-GHz-band 21-GHz-band satellite satellite Communications Relay satellite broadcasting station (SFN)

Relay SNG van broadcasting Super HiVision station (SFN) Communications network

Broadcasting Broadcasting Center station Mobile (master) Shinkansen reception Outside relay broadcasting Reception using mobile terminals Car Studio Wireless network

Overview of research being conducted by the Wireless Systems Department

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