They do run 8-PSK modulation on some of the Ka band local spotbeams, since they have a higher PFD. Such as the ones covering the LA market here (A1BB and A4BB from 103W).I kind of remember HD ran in the 8mb/s range before I retired with five channels per 36MHz Ka transponder and I thought they were running 8-PSK back then. I have the data somewhere but I'm sure many here have old and new rates if they have changed.
But never for the Ka CONUS ones.
As those are always QPSK at a 2/3 FEC as slice noted earlier. ....
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