DVB-S2
DVB-S2 is a newer specification of the DVB-S (Digital Video Broadcasting) standard. Designers claim that DVB-S2 performance gains over DVB-S is circa 30%. Unlike DVB-S, it does not rely on MPEG-2 encoding alone, but allows more advanced encoding, like H.264 (a.k.a. MPEG-4 Part 10 or AVC) or VC-1. Main features: - DVB-S2 combines DVB-S (intented for final consumers ) with DVB-DSNG (used by professionals),
- Adaptative coding to optimize the use of satellite transponders.
- 4 modulation modes are available : QPSK, 8PSK (used in non-linear transponders near to saturation); 16APSK and 32APSK (for professional, semi-linear aplicatons).
- Improved rolloff: α = 0.20 and α = 0.25 in adition to the DVB-S α = 0.35.
- Forward error correction: DVB-S2 uses a FEC system based on concatenation of the Bose-Chaudhuri-Hochquenghem code with a low density parity check. Performance should be 0.7 dB close to the Shannon limit.
- Cheap to implement.
External link - DVB-S2 white paper (final)
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