Method and apparatus for fault segmentation in a telephone network

Apparatus for segmenting faults in the physical transport media of a telecommunications network having a plurality of lines, comprising:

• a) means for measuring a plurality of electrical parameters characterizing a selected line;
• b) memory means, connected to the means for measuring, for storing a plurality of electrical parameters characterizing the selected line at a first time;
• c) means, connected to the memory means and the means for measuring, for comparing the stored parameters to parameters measured on the selected line at a second time and determining the location of a fault in said telecommunications network based on the change in the parameters;
• d) wherein the network comprises a telephone network and each of the lines comprises a plurality of subscriber lines terminating in premises wiring and the means for determining the location of a fault distinguishes between faults in the premises wiring and faults in other parts of said telecommunications network;
• e) wherein the means for determining the locations of a fault comprises a computer programmed with:
• i) a plurality of expert systems, each of which has an output representing a prediction of the location of a fault;
• ii) a means for selecting a fault location based on the outputs of the plurality of expert systems.

Apparatus for segmenting faults in a network having a plurality of lines, each line having at least a pair of wires, comprising:

• a) means for measuring parameters characterizing a selected line;
• b) memory means, connected to the means for measuring, for storing parameters characterizing the selected line at a first time;
• c) means, connected to the memory means and the means for measuring, for comparing the stored parameters to parameters measured on the selected line at a second time and determining the location of a fault in the network based on the change in the parameters;
• and
• d) wherein said means for measuring comprising:
• i) measurement hardware having at least two terminals and a control input, comprising:
• A) means for generating a voltage pulse at the two terminals in response to a control signal at the control input;
• B) means for recording a reflected signal at the two terminals;
• ii) access means, having a control input, for connecting the two terminals of the measurement hardware to a selected one of the plurality of lines through the switch in response to a control signal at the control input;
• and
• iii) a computer processor having control lines connected to the control inputs of the measurement hardware and the access means.

Apparatus for segmenting faults in the physical transport media of a telecommunications network having a plurality of lines, comprising:

• a) means for measuring a plurality of electrical parameters characterizing a selected line:
• b) memory means, connected to the means for measuring, for storing a plurality of electrical parameters characterizing the selected line at a first time;
• c) means, connected to the memory means and the means for measuring, for comprising the stored parameters to parameters measured on the selected line at a second time and determining the location of a fault in said telecommunications network based on the change in the parameters
• d) wherein the means for comparing the stored parameters to parameters measured on the selected line at a second time and determining the location of a fault in the network based on the change in the parameters comprises an expert system of the type constructed from a plurality of expert subsystems each providing inputs to an arbitrating expert and having at least two of the expert subsystems operate on different paradigms.

An automatic test system for segmenting faults in a telephone network, the network including a plurality of cables, each of said cables carrying a plurality of subscriber loop lines, each subscriber loop line having a plurality of segments including at least a cable segment within the cable and a premises wiring segment outside the cable, the automatic test system comprising:

• a) means for measuring parameters of the subscriber loop lines;
• b) memory for storing representations of measured parameters of a plurality of subscriber lines;
• c) control means, coupled to the measuring means and the memory, for:
• i) at a first time, initiating measurement of parameters of a plurality of the subscriber lines and for controlling the memory means to store representations of the measured parameters, and
• ii) at a second time, initiating measurements of a selected subscriber line and comparing selected stored representations to the measurements and indicating, based at least in part on the comparison, a prediction of a fault and the segment of said plurality of segments in which the fault occurs.