Twisted pair cables are usually grouped together in a binder where they experience crosstalk. Based on empirical observations, Unger [1] proposed that, at the 1% worst case, the NEXT power spectra , due to a single disturber, can be bounded by
while the NEXT power spectra due to 49 disturbers (full binder) can be bounded by
References
^J. H. Unger, "Near-End Crosstalk Model for Line Code Studies", ECSA Contribution, T1D1.3/85-244, November 12, 1985.