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DTV Goes Mobile In Japan

by Eizo Shimbun~ April 25, 2006

On April 1, 2006, 22 broadcasters in Japan began "1-Segment Broadcasting," or "1-Seg" for short, a terrestrial broadcast service that transmits digital television to mobile devices, including cell phones and in-car navigation systems. 1-Seg service is available in Tokyo, Osaka, Nagoya and other large cities where terrestrial digital broadcasting is available.

TV-Keitai (cell phones), available since 2003, have been broadly adopted in major markets. Advanced "TV-Keitai" (TV-cell phone) models from KDDI(au) and NTT DoCoMo are equipped to receive the signal.

Japan's Integrated Services Digital Broadcasting-Terrestrial (ISDB-T) standard defines the protocol for a 6 MHz channel to be divided into 13 segments. Several segments may be bundled together to transmit images, audio, interactive data and so on. ISDB-T 1-Segment broadcasts use one of these segments to transmit to mobile devices. 1-Seg uses QPSK modulation and a 2:3 coding ratio for error correction, at a data transmission rates of 400 kbps or 256 kbps for image/sound.

Network operators hope that mobile TV will have a promising future in the handheld industry, as broadcast networks and mobile network operators are looking for unique programs and content to establish successful business models. Nippon TV and Fuji TV are each providing more than 10 simulcast programs. TBS is providing non-simulcast programming linked to its TV shopping channels. TV Tokyo features real-time updates and in-depth market information with non-simulcast programming. These plans may prove to be successful, although they are all still in an experimental stage.

To simulcast their programming, most broadcast networks are using automatic conversion systems to convert their own news, weather and program guides, or emergency information to their 1-Segment broadcast. However, these closed systems make it much more problematic to rebroadcast a signal from another network, such as an emergency broadcast program after a natural disaster. It will take substantial effort and signal manipulation for broadcasters to cooperatively provide emergency broadcast programming.

In addition, simulcasting programs to the 1-Segment broadcast incurs extra costs for conversion. Program producers will have to realize and absorb this additional cost when starting a project. Following is a summary of the 1-Seg programming being offered by some networks.

On April 1, NHK began 1-Segment broadcasting in 29 regions throughout Japan. Content includes news, weather, program and mobile link information. As a public broadcaster, information of various disasters must be widely distributed, even to remote regions of Japan. NHK is providing a TV data link function, enabling users to capture additional data information from 1-Segment broadcasts.

Currently simulcasting more than 10 programs, NIPPON TV is one of the most active. The target time zones are morning, evening and prime time. Morning programs such as "Zoom In" provide news, entertainment and weather information.

TV Asahi provides three simulcast broadcasts with data communication functions. Non-simulcast programming, such as news and weather information with links to additional data, also are an important feature, so TV Asahi is designing optimized content for 1-Segment broadcasting, with attention to every detail including image design.

In addition to news, weather and emergency information, such as earthquakes, TBS is developing non-simulcast programming for 1-Segment, with an emphasis on having a user-friendly interface. TBS TV Shopping is one of their featured programs.

TV Tokyo is focusing on stock market information including Nikkei Index reports and updates, as well as international stock markets and currency exchange rates. Two informational programs in prime time and a business information program are being provided. A data broadcast for educational studies also is being tested.

Fuji TV will gradually increase its simulcast and non-simulcast programming of news, variety, drama and sporting events. Currently more than 10 programs are simulcast during prime time.

© 2006 NAB