Quote:
Originally Posted by old_tv_nut
I agree with all of this except the efficiency comparison. DVB-T and ATSC are essentially equal in efficiency for the same robustness level of channel coding (but DVB-T has multiple trade-offs of efficiency vs. robustness available). DVB-T2 uses more efficient error protection coding, which will very likely be adopted for ATSC 3.0 as well.
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Thanks for the info on relative efficiency of the systems. COFDM makes it inherently easy to trade robustness for bit rate. Even to the point where single frequency networks can be used, because co-channel interference can be rejected in the same way as multipath. It's just a matter of choosing a guardband that adequate and accepting the resultant loss of bit rate. SFNs have not been used in the UK. I don't know about elsewhere.
It's worth noting that COFDM isn't needed on satellite broadcasting systems. The channel is inherently not subject to multipath or selective fading. These are the things that are dealt with by COFDM's multiple carriers, each with low bit rate, plus guard bands. A satellite channel has very high losses due to distance, plus rain fade. These cannot be helped by COFDM. There are also rare occasions when the sun aligns with the satellite. Reception is then impossible for a short period.