Beginner level : Help with terminologies : smooting length, length of channel, channel equalization delay, blind system identification, equalization
The term smoothing length (also called observation interval) is simply the length of the equalizer, i.e. its number of filter taps. In the code the filter length is L+1, so L is the filter order. Similarly, the length of the channel refers to the length of the FIR filter simulating the dispersive channel. Again, the channel filter length is actually ChL+1. What is called equalization delay in the code is the total delay introduced by the channel and by the equalizer. It is needed for aligning transmitted and received (and equalized) symbols.