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The delivery of digital radio, via satellite, promises to reduce the information gap between the developing and developed worlds.
For over seven decades, most developing countries - for their radio service - have had to rely on inferior quality short wave (HF) or high-powered medium wave AM broadcasting. And when you consider that one million to two million people per station is a typical ratio in the developing world (combined with the fact that there is negligible alternate media choice for information) it is clear that this part of the world lags considerably behind developed nations. In developed countries, there are typically 30-50,000 people per station, with other media providing alternate choice for information. This yawning digital divide can be reduced, however, by direct satellite digital radio reception.
At the ITU WARC '79, developing countries proposed spectrum allocation for experimental satellite radio broadcasting. Although an allocation was not agreed, the initiative led to what became a decade of technical studies in the ITUCCIR leading to informed technical and economic comparative information for consideration in the potential deployment of BSS (Sound) in L and S bonds. Also, by the end of that decade digital technology was already being proven beneficial for some applications.
Thus, for WARC 92, the agenda provided for consideration of spectrum allocation for satellite DRB and complementary terrestrial broadcasting (seen at the time as primarily for gap filling). WARC 92 established a worldwide allocation of 40MHz in the 1452-1492MHz frequency band, with initial systems confined to use of 1467-1492MHz under approved coordination provisions, with the remaining 15MHz to be the subject of planning considerations at a subsequent conference.
WorldSpace: a hybrid solution
The original WorldSpace design concept was for delivery of digital sound broadcasting (DSB) services via satellite for reception by inexpensive indoor/outdoor fixed and portable, personal, low cost receivers. Services are operational throughout Africa and Middle East and parts of Europe (AfriStar), as well as Asia/part Pacific (AsiaStar) and the Caribbean and Latin America (AmeriStar).
The specifications have received international recognition and have been approved by the ITU as a worldwide standard for DSB, known as Digital System DS - it is a recommended preferred transmission means to portable personal receivers.
WorldSpace has also recently developed and...