Method and apparatus for measuring AC shield continuity for shielded twisted pair structured datacomm cable link
AssigneeFluke Corporation
InventorsJeffrey Sandsmark Bottman, Jun Ho Yi
Life of this patent
Estimating the term…
Abstract
AC shield continuity for shielded twisted pair structured datacomm cable is determined by testing the cable, driven in a common mode, over a range of frequencies, to determine presence and location of shield breaks. DC ground path generated false results are thereby avoided.
Claims12
A method for measuring ac shield continuity for shielded twisted pair structured datacomm cable having plural twisted pairs, comprising:
- applying a test signal in common mode to plural ones of said twisted pairs;
- measuring response to said applying step to determine shield continuity;
- finding primary peak values and their time-location and secondary peak values and their time-location in the converted time-domain value;
- and
- determining whether the primary peak values are greater than a value q times a theoretical peak value;
- if the primary peak values are greater than q times the theoretical peak values, determining a continuity problem exists for a cable segment.
A method of testing for shield continuity in shielded cabling having plural twisted pairs, comprising:
- launching a TDR test signal into the cabling driven in common mode;
- obtaining a measured complex reflection coefficient from the cabling;
- converting the measured complex reflection coefficient into a time-domain value;
- finding primary peak values and their time-location and secondary peak values and their time-location in the converted time-domain value;
- determining whether the primary peak values are greater than a value q times a theoretical peak value;
- if the primary peak values are greater than q times the theoretical peak values, determining a continuity problem exists for a cable segment.
A shield continuity testing device for testing shield continuity in shielded cabling having plural twisted pairs, comprising:
- a TDR test signal generator for providing test signals into the cabling driven in common mode;
- a TDR receiver for obtaining a measured complex reflection coefficient from the cabling in response to the test signals from the generator;
- a processor operative for converting the measured complex reflection coefficient into a time-domain value, finding primary peak values and their time-location and secondary peak values and their time-location in the converted time-domain value, determining whether the primary peak values are greater than a value q times a theoretical peak value, and if the primary peak values are greater than q times the theoretical peak values, determining a continuity problem exists for a cable segment.
Dependencies are inferred from the claim text.