Method and a System for Cable or Subscriber Loop Investigation Performing Loop Topology Identification

A method of determining a plurality of current characteristics of a transmission line having an unknown number of cable segments (S1, . . . , SN) of unknown length and impedance, said method performing a loop topology identification by performing the steps of:

• modelling and estimating characteristics of a first segment of the transmission line;
• iteratively modelling and estimating characteristics of subsequent segments based on the estimated characteristics of the first segment consecutively toward a termination end of the transmission line;
• and
• transforming the estimated characteristics of the segments to the time domain such that a loop topology identification is provided iteratively providing information about the plurality of current characteristics for the total transmission line.

A system for determining a plurality of current characteristics of a transmission line having an unknown number of cable segments of unknown length and impedance, wherein the system performs a loop topology identification, said system comprising:

• means for modelling and estimating characteristics of a first segment of the transmission line;
• means for iteratively modelling and estimating characteristics of subsequent segments based on the estimated characteristics of the first segment consecutively toward a termination end of the transmission line;
• and
• means for transforming the estimated characteristics of the segments to the time domain such that a loop topology identification is provided iteratively providing information about the plurality of current characteristics for the total transmission line.