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Gidi Raz. Maximizing Satellite Transmission Efficiency With DVB-S2. Agenda. The Challenge What is DVB-S2 DVB-S2 New Tools & Technologies DVB-S2 Business Model. The Challenge. Transmission costs (1.5-2M$ / 36 Mhz / Year) Increasing number of channels
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Gidi Raz Maximizing Satellite Transmission Efficiency With DVB-S2
Agenda • The Challenge • What is DVB-S2 • DVB-S2 New Tools & Technologies • DVB-S2 Business Model
The Challenge • Transmission costs (1.5-2M$ / 36 Mhz / Year) • Increasing number of channels • Moving to HD – High bandwidth consumer • Reduce OPEX / CAPEX • Limitations in current DVB-S and DVB-DSNG
So what do we need? • Increased data throughput in a given bandwidth, or • Use less satellite capacity and save money • Increased availability through improved link margin – More robust • Increased coverage area • Smaller dish DVB-S2
What is DVB-S2 ? • New DVB standard for digitial satellitecommunications • Up to 30% bandwidth saving • Up to 2.5 dB margin gain • Meant to replace DVB-S & DVB-DSNG New features such as: • Support of multiple streams on a single carrier • Variable and Adaptive Coding and Modulation • Much better spectral efficiency So close to the Shannon limit that it could be the last DVB-S standard! Shannon's Law Expresses the maximum possible data speed that can be obtained in a data channel. Shannon's Law says that the highest obtainable error-free data speed, expressed in bits per second (bps), is a function of the bandwidth and the signal-to-noise ratio
Short Example Using 36Mhz transponder using different modulation and compression scheme
DVB-S2 Why the new system? 2.5dB = 33% more useful data rate, or 2.5m Vs. 4.5m antenna Shannon limit DVB-S & DSNG DVB-S2 2.5 dB margin gain signal-to-noise ratio
DVB-S2 and Broadcast applications (DTH) Typical 36MHz transponder usage with DVB-S and DVB-S2: SATELLITE EIRP 51 dBW SATELLITE EIRP 53.7 dBW DVB-S DVB-S2 DVB-S DVB-S2 27.5 Mbauds (ROF 0.35) 30.9 Mbauds (ROF 0.20) 27.5 Mbauds (ROF 0.35) 29.7 Mbauds (ROF 0.25) Symbol Rate Roll-Off factor Modulation QPSK 2/3 QPSK 3/4 QPSK 7/8 8PSK 23 33.8 Mbps 46 Mbps (+36%) 44.4 Mbps 58.8 Mbps (+32%) Bit rate 7 SDTV MPEG2 15 SDTV h.264 10 SDTV MPEG2 21 SDTV h.264 10 SDTV MPEG2 20 SDTV h.264 13 SDTV MPEG2 26 SDTV h.264 Number of SD channels Number of HD channels 1 HD MPEG2 3 HD h.264 2 HD MPEG2 5 HD h.264 2 HD MPEG2 5 HD h.264 3 HD MPEG2 6 HD h.264
DVB-S2 SYSTEM Tools • Powerful FEC system based on LDPC (Low-Density Parity Check) codes • Wide range of code rates (from 1/4 up to 9/10) • New Modulation schemes ranging from 2 to 5 bit/second/Hz spectrum efficiency - QPSK, 8PSK, 16APSK, 32APSK • Set of three spectrum shapes with roll-off factors 0.35, 0.25 and 0.20 • Flexible stream adapter, suitable to operate with single and multiple TS on the same carrier with different modulation and FEC • Variable & Adaptive Coding and Modulation (VCM/ACM) functionality, allowing to optimise channel coding and modulation on a frame-by-frame basis.
New Modulation Constellations QPSK 2 bits/symbol 8PSK 3 bits/symbol 16APSK 4 bits/symbol 32APSK 5 bits/symbol
Three Operation Mode • CCM Constant Coding and Modulation • All frames use the same (fixed) parameters • VCM Variable Coding and Modulation • Different streams/services are coded with different (fixed) parameters on the same carrier • ACM Adaptive Coding and Modulation • Each frame is coded with its own set of parameters. Parameters are modified dynamically according to the reception conditions for each receiver
Distribution of multiple TS multiplexes • DTT Transmitters • (Multiple TS, Constant Code Modulator - CCM) DVB-S2 Modulator QPSK Rate 5/6 Mode adapter DTT MUX 1 1 SD MERGER Stream Adapter FEC Coder Mod Transport Stream 1 SD DTT MUX 2 Transport Stream 2 2 SD Constant Coding & Modulation SD
Distribution of multiple TS multiplexes • Perfect fit for DVB-T distribution • 2 Transport streams of 24 Mbps on single carrier (36 Mhz) • Can carry more than 30 Mpeg4/SD channels or 6-8 HD Channels
Applications- SDTV and HDTV broadcasting 2. Differentiated channel protection (Variable Code Modulation, Multiple TS - VCM) DVB-S2 Modulator QPSK Rate 3/4 Mode adapter MUX 1 1 SD MERGER Stream Adapter FEC Coder Mod Transport Stream 1 SD MUX 2 HD Transport Stream 2 2 16 APSK Rate 3/4 HD
Applications 3. DSNG Services using ACM (Single Transport Stream, information rate varying in time)
Two Examples • Contribution • Delivering 5 Mbps from point to point • DBV-S: QPSK ¾ , with roll off factor of 0.35 requires 4.88 Mhz • DBV-S2: QPSK 9/10 , with roll off factor of 0.2 requires 3.37 Mhz • Total bandwidth saving of 30% • Total cost saving is $70,000 a year (ROI 5 Months) • Distribution • Distribution of 10 channels to 10 location (average 3.5 Mbps/Ch.) • DBV-S: QPSK ¾ , with roll off factor of 0.35 requires 34.18 Mhz • DBV-S2: QPSK 9/10 , with roll off factor of 0.2 requires 23.86 Mhz • Total bandwidth saving of 30% • Total cost saving is $620,000 a year (ROI 5 Months)
Summary Take advantage of the new technology Mpeg4 / DVB-S2 Save at least 30% bandwidth / Money