[syntaxing]

So interesting! How do you send "error-resistant digitally modulated transmissions"? Is that the same thing as a duplex signal? Is there other technology used nowadays?

[howard941]

Could be coding (Turbo coding is where it's at, while hamming (no relation) error correcting codes are purely digital and ubiquitous), could be simple double transmissions separated in the time domain as in FEC SITOR/AMTOR. My money's on Turbo coding. https://en.wikipedia.org/wiki/Turbo_code

[syntaxing]

Super interesting! Is this still the standard for this sort of communication nowadays or are there successors?

[ww520]

It's probably error corrected code. Some examples are CRC, ECC menory, and Raid-5 disk array.