Tradeoff between coding gain and
latency
Codec Performance Latency Used Where
DVB-S2 LDPC
Long Block
Best throughput
vs. power
>100ms @ 2Mb
<25ms @ 10Mb
One-Way and
High Speed 2
way to mitigate
latency
Comtech
VersaFEC
~ 0.3dB worse
than DVB-S2
LDPC Long
Block
<3ms @ 2Mb Duplex latency
sensitive links
with excellent
performance
Turbo Coding ~ 1.3dB worse
than DVB-S2
LDPC
<2ms @ 2Mb Extremely low
latency open
standard
Viterbi + RS
(DVB-S)
~ 2.5dB worse
than DVB-S2
LDPC
<3ms @ 2Mb Legacy networks
where hardware
is in place
Comtech Proprietary & Confidential
15
