This Blog chronicles my current radio developments.
Sunday, 28 January 2018
DVB-S2X First Light
Initial DVB-S2X decoding has now been added to the soft modem.
With almost 100 different modulation formats I have little hope of implementing
them all but it is a start.
It is interesting to see that S2 has some amplitude modulation. It may face similar issues to DVB-T for power amplifiers and distortion. Is pre-distortion possible?
Hi, in truth all coherent phase modulations have instantaneous zero power crossings, making them AM in all but name. Now CPM (Continuous Phase Mod) in all varieties does not suffer this. Hence GMSK. See Dr Kamilo Feher.ISBN 0-13-098617-8 - cheers, IanW.
Nice work Charles.
ReplyDeleteIt is interesting to see that S2 has some amplitude modulation. It may face similar issues to DVB-T for power amplifiers and distortion. Is pre-distortion possible?
Hi, in truth all coherent phase modulations have instantaneous zero power crossings, making them AM in all but name. Now CPM (Continuous Phase Mod) in all varieties does not suffer this. Hence GMSK. See Dr Kamilo Feher.ISBN 0-13-098617-8 - cheers, IanW.
ReplyDelete