The DVB-S2 standard (EN 302 307) defines the second-generation modulation and channel coding system for satellite TV to make use of the improvements that have emerged since the publication of the DVB-S standard. DVB-S2 is a single, very flexible standard covering a variety of applications by satellite.
DVB-S2 is the next logical step in the continuous development of DVB-S. Innovative and more efficient channel coding methods combined with higher-order modulation modes enable operators to transmit up to 30 % more data when using DVB-S2 as compared to DVB-S at the same transponder bandwidth and EIRP.
The system has been optimized for digital multiprogram television broadcasting services and high definition television (HDTV) broadcasting services to be used for primary and secondary distribution in the fixed satellite service (FSS) and the broadcasting satellite service (BSS) bands.
It features the following:
- A flexible input stream adapter, suitable for operation with single and multiple input streams of various formats (packetized or continuous)
- A powerful FEC system based on low-density parity check (LDPC) codes concatenated with BCH codes, allowing quasi-error-free operation at approx. 0.7 dB to 1 dB from the Shannon limit, depending on the transmission mode
- A wide range of code rates from 1/4 up to 9/10
- Four constellations (QPSK, 8PSK, 16APSK, 32APSK), ranging in spectrum efficiency from 2 bit/s/Hz to 5 bit/s/Hz, optimized for operation over non-linear transponders
- A set of three spectrum shapes with roll-off factors of 0.35, 0.25 and 0.20
- Variable coding and modulation (VCM) may be applied in order to provide different levels of error protection to different service components (e.g. SDTV and HDTV, audio, multimedia)
- In the case of interactive and point-to-point applications, the VCM functionality may be combined with the use of return channels to achieve adaptive coding and modulation (ACM). This methods provides the best-suited channel protection and dynamic link adaptation to propagation conditions, targeting each individual receiving terminal