Method for measuring line parameters of subscriber lines of a telephone network

摘要

In six different measuring configurations, a pulse voltage is impressed on the wires of the subscriber line while the other wire is respectively earthed and the respective pulse response is measured or these wires are again discharged to earth and the discharge voltages measured at discrete times. In each case prior to analog-digital conversion, which precedes the digital measured value evaluation, a value of the difference between the initial voltage value occurring at the start of the discharging process and the respective measured value occurring at a discrete measuring time is formed and subjected to amplification in order to obtain from the measured values an appropriate pattern in the discharge curve, even in the case of lines with a large time constant, from which the line parameters are then calculated. IMAGE