Sym Time Adjustment (DOCSIS 4.0 Upstream)

Sym Time Adjustment shifts the start of the TFFT period earlier in the symbols. You specify the amount of TFFT shift as a percentage of the TFFT length.

The Auto setting detects and applies the proper time adjustment.

If you want to see the Auto setting's symbol time adjustment value to use as a starting point for manual adjustment, see Sym Time Adjustment in the Error Summary trace.

Moving the TFFT period away from the ending transition time (TTR) into the guard interval (TGI) may help avoid intersymbol interference. Make sure that the TFFT period is not shifted so much that it includes corrupt data from the transition time at the beginning of the symbols.