Newtec Proprietary
Confidentiality: Unrestricted
V1.4
218/225
Appendix B - Overview of the Used Technologies M6100 Broadcast Satellite Modulator
– One set of ModCods is optimized for multi-carrier operation of the transponder (linear
channel operation). In multi-carrier operation, the transponder can not be saturated and a
given back-off is needed to avoid intermodulation between the individual carriers in the
transponder.
– The second set of ModCods is optimized for single carrier operation which allows to saturated
the transponder (non-linear channel).
15.2.1 Performance of S2 Extensions
Newtec's implementation of the S2 Extensions increases the modulation and coding schemes and
Forward Error Correction (FEC) choices (compared to DVB-S2), which then can provide the highest
resolution for optimal modulation in all circumstances. The current DVB-S2 quantization steps are
quite far apart. By adding granularity in the upcoming standard the service provider can further
optimize the satellite link depending on the application. In combination with Adaptive Coding and
Modulation (ACM), where the highest MODCOD is selected automatically, full efficiency can be
gained. The amount of MODCODs has grown from 28 in DVB-S2 up to 87 in the S2 Extensions
bringing efficiency as close to the theoretical Shannon limit as possible.
Adding higher modulation schemes such as 64APSK proves to be useful considering the
professional applications that work with improved link budgets provided by more powerful satellites
that become available. Newtec sees the 32APSK boundary being reached frequently with FlexACM
during clear weather conditions. In these situations 64APSK is highly beneficial.
When combining the increased granularity (MODCODs and FECs) and 64 APSK (higher order
modulation and coding) immediate efficiency gains up to 37% can be achieved compared to
DVB-S2. The following figure shows the performance of S2 extensions compared to DVB-S and
DVB-S2.
To Next Page
Loading...
