Patent ID: 7508219
Filing Date: 2009-03-24
Classification: H04M

Abstract:
1. A system for determining insertion loss of a telephone line under test (LUT) comprising: means responsive to electrical stimulation of an input of the LUT at each frequency of a plurality of discrete frequencies for predicting a length d of the LUT at said frequency; means for determining a running standard deviation of the length d of the LUT at each frequency of the plurality of discrete frequencies, wherein the running standard deviation at each frequency is determined as a function of the predicted lengths d determined for the LUT at and below said frequency; means for determining a mean length (dm) of the LUT as a function of the lengths d of the LUT determined for each frequency at and below the pair of adjacent frequencies where the largest difference between running standard deviations occurs; means for determining a gauge of the LUT as a function of the running standard deviation of the one of said pair of adjacent frequencies; and means for determining an insertion loss value of the LUT as a function of the gauge and the mean length dm.