Analysis of Crosstalk Data for Maximizing PCM System Application

This paper addresses the general problem of estimating the maximum number of PCM systems allowed on one cable repeater section given representative PCM repeater characteristics and cable data. NEXT is analyzed, and a regenerative repeater is characterized by a graph of acceptable NEXT attenuation versus repeater section loss. Crosstalk data are utilized by statistical summation (convolution) using a flexible method based on cumulants (semi-invariants) which can deal with multiple subpopulations. An example calculation is given to illustrate the procedure for a simplified case. The relationship between the standard deviations for single frequency measurements and widebank crosstalk is discussed.