A Report on the Technical Condition of Digital Terrestrial Sound Broadcasting

On digital terrestrial sound broadcasting, a draft standard was established by the Telecommunications Technology Council in November, 1998, followed by large-scale verification tests conducted by the ARIB (Association of Radio Industries and Businesses). Based on the test results, the technical condition of broadcasting systems was reported on in November, 1999.

Digital terrestrial sound broadcasting systems reported on this time include the following characteristics:

  • Diverse broadcasting services are possible that feature high quality sound broadcasts in addition to data form information (incl. text, still pictures, and simple animation).
  • Adoption of an OFDM (Orthogonal Frequency Division Multiplexing) modulation scheme that is less affected by multi-pass disturbances, enabling SFN (Single Frequency Network) .
  • Stable mobile and portable reception under severe conditions.
Adoption of the MPEG-2 standard, which is commonly used with digital satellite broadcasting, and the adoption of the same signal structure for use with digital terrestrial television broadcasting, is expected to bring lower receiver prices to the market. Also desired is the realization of attractive new services such as multimedia services for mobile reception as well as high-quality sound services, for which it is essential to diffuse digital terrestrial sound broadcasting as a new broadcasting medium. Present AM and FM broadcasting services will remain as they are now. Digital terrestrial sound broadcasting will appear as a new service, scheduled to start in areas where frequency allotments are possible.


Data Broadcasting Verification Test Conducted

The XML System Working Group of the ARIB (Association of Radio Industries and Businesses) Digital Satellite Broadcasting System Development Sector started examining XML-based multimedia coding in March last year. The Working Group completed a proposal in September, verifying the feasibility of an actual data broadcasting system based on the equipment backed by its experiment results.
The test was performed in one of the conference rooms of the NHK Integrated Technology Inc. Tokyo head office in September last year. An observation was also held, attended by parties concerned from the Telecommunications Technology Council and ARIB. The following functions were verified by the test;

  • The appropriate display of still pictures and text layout as intended by the production process.
  • Proper Screen changes according to the selection of inputs on a menu display.

The following application contents were also verified;

  • An independent service which provides artistic still images with sound.
  • Financial information (such as for stock markets).
  • Supplemental information services, which provide information directories for places of interest and popular stores in a town.
  • Internet home page contents converted for broadcasting use.
Based on the results of these verification tests, a standard for the data broadcasting system including multimedia coding, was approved at the ARIB Standard Assembly held on October 26 last year. Now it can be said that the standards for digital satellite broadcasting are well-established.