The DVB-T2 specification was approved by the DVB Steering Board in June 2008 and sent to ETSI for adoption as a formal standard. Lastly, DVB-T (VHF/UHF) uses 16-QAM or 64-QAM (or QPSK) in combination with (C)OFDM and can support hierarchical modulation. QPSK and 8-PSK are the only versions regularly used. DVB-S2 uses QPSK, 8-PSK, 16-APSK or 32-APSK, at the broadcasters decision. DVB-S ( SHF) uses QPSK, 8-PSK or 16- QAM. These distribution systems differ mainly in the modulation schemes used and error correcting codes used, due to the different technical constraints. A standard for temporally-compressed distribution to mobile devices (DVB-H) was published in November 2004. All data is transmitted in MPEG transport streams with some additional constraints (DVB-MPEG).
DVB LIVESTATION SERIAL
Devices interact with the physical layer via a synchronous parallel interface (SPI), synchronous serial interface (SSI) or asynchronous serial interface (ASI). These standards define the physical layer and data link layer of the distribution system. Microwave: using DTT ( DVB-MT), the MMDS ( DVB-MC), and/or MVDS standards ( DVB-MS).Digital terrestrial television for handhelds: DVB-H, DVB-SH.DVB systems distribute data using a variety of approaches, including:
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