Quote:
Originally Posted by DABhand
SCDMA has other benefits, it can utilize 128QAM with TCM (Trellis Coded Modulation). Also the fact that there is not time slots assigned per modem on the upstream, so modems can transmit Asynchronous, but as some people know ATDMA is not Asynchronous and assigns time slots to each modem on the same node so it is not a continuous data transmition.
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SCDMA is less efficient than ATDMA. 128QAM requires an insane upstream SNR, 64QAM is a challenge for operators to push to let alone another 3dB to cater to 128QAM and after overheads it doesn't actually provide anything more than 64QAM ATDMA.
SCDMA does indeed have a purpose, it is more resilient in the presence of burst noise that ATDMA, however horses for courses. If it were so evidently superior everyone would be doing it. They aren't.