Network users of ST Engineering iDirect now have the opportunity to upgrade their Evolution® networks.

Using Universal Line Cards and new network software enables you to take full advantage of DVB-S2X efficiencies which include Adaptive Coding and Modulation (ACM) and up to 119 Msps in DVB-S2X forward carriers.

When you have high C/N, higher order MODCODs should be investigated, allowing 64APSK, 128APSK and 256APSK. These higher order modulation methods, combined with suitable FEC rates, substantially increase your bit rate for a given satellite transponder bandwidth. Since the system is adaptive this means that instead of having wastefully large C/N rain margins in clear sky you can increase the bit rate during clear sky. This also applies if you have transitioned to a more powerful EIRP satellite.

BPSK gives 1 transmission rate bit per symbol
QPSK  gives 2 transmission rate bits per symbol
8APSK gives 3 transmission rate bits per symbol
16APSK gives 4 transmission rate bits per symbol
32APSK gives 5 transmission rate bits per symbol
64APSK gives 6 transmission rate bits per symbol
128APSK gives 7 transmission rate bits per symbol
256APSK gives 8 transmission rate bits per symbol

With iDirect sharper roll off filtering your symbol rate increases towards the leased transponder bandwidth.

Your information bit rate is transmission bit rate x FEC ratio.

Contact you iDirect sales representative for more details.

More about Bandwidth, symbol rate, transmission rate and modulation method, fec rate and customer information rate.

I've just found the relevant technical brief document about iDirect DVB-S2X Evolution.

There is an excellent graph relating C/N and spectral efficiency (Bits per Symbol) and the improvement from going from DVB-S2 to DVB-S2X.

There is also a table showing the available modulation methods and FEC ratio options for each.

Download (pdf):
https://www.idirect.net/wp-content/uploads/2020/03/TechBrief-DVB-S2X-Evolution.pdf