A DTV signal has a plural-data-segment frame header including complementary first
and second ghost-cancellation reference signals differentially delayed by the duration
of two NTSC horizontal scan lines. A receiver for such DTV signal has an adaptive
equalizer for baseband symbol code with kernel weights calculated by a computer
operative on the equalizer response after comb filtering. The comb filter combines
the equalizer response as differentially delayed by the duration of two NTSC horizontal
scan lines to cancel artifacts of co-channel NTSC interference in the comb filtered
equalizer response supplied to the computer. This reduces the undesirable influence
of such artifacts on equalization to reduce intersymbol interference.