Digital Video Broadcasting: Technology, Standards and Regulations
An overview of the technical, political, and market issues relating to digital video broadcast and digital television.
TABLE OF CONTENTS Digital Video Broadcasting: Technology, Standards and Regulations
10.5 Summary and conclusions
DVB has provided specifications for a broad variety of digital transmission systems concerning communication via satellite, CATV, and terrestrial networks. These systems have been or are currently being standardized by ETSI. Table 10.7 provides an overview of the typical parameters of the DVB digital transmission systems.
Satellite communication suffers from power limitations. For this reason, QPSK is used as a modulation method. The advantage of satellite communication is the rich availability of bandwidth, which in the end allows a high bit rate. After receiving the satellite signals, further transmission via a SMATV network is enabled by the DVB SMATV system. This allows the use of QAM, but the available bandwidth is limited. Hence, a DVB System lower bit rate is achieved. This last case more or less applies to the DVB cable system as well.
Table 10.7: Typical DVB Digital Transmission System Parameters
| Modulation | Frequency Band (GHz) | Signal Bandwidth (MHz) | Bit Rate (Ru) (Mbps) | |
|---|---|---|---|---|
| DTH | QPSK | 11/12 (downlink) | 26.0 54.0 | 18.7 68.0 |
| SMATV | 16-QAM 32-QAM 64-QAM | 0.23 0.47 or 0.95 2.05 0.23 0.47 or 0.95 2.05 0.23 0.47 or 0.95 2.05 | 5.9 7.9 4.7 8.0 3.9 8.0 | 18.9 25.2 18.9 31.9 18.9 38.1 |
| CABLE | 16-QAM 32-QAM 64-QAM | f f f | 2.0 7.9 2.0 8.0 2.0 7.9 | 7.0 27.3 8.7 34.6 10.4 41.3 |
| TERRESTRIAL | OFDM (QPSK) OFDM (16-QAM) OFDM (64-QAM) | 0.3 3.0 0.3 3.0 0.3 3.0 | 7.6 7.6 7.6 | 5.0 10.6 10.0 21.1 14.4 31.7 |
| MVDS | QPSK | 40.5-42.5 | 26.0 54.0 | 18.7 68.0 |
| MMDS | 16-QAM 32-QAM 64-QAM | f < 10 f < 10 f < 10 | 2.0 7.9 2.0 8.0 2.0 7.9 | 7.0 27.3 8.7 34.6 10.4 41.3 |
| Notes: |
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