Systems and methods for line attenuation testing

Abstract

A system for testing line attenuation defects includes a data transmission line configured to transmit a forward signal in a first direction, at least one reflection point at a first location along the data transmission line, a test probe configured to (i) electrically contact a center conductor at a second location along the data transmission line, (ii) introduce a broadband data signal onto the data transmission line, and (iii) measure, at the second location, a return signal from the reflection point, and a spectrum capturing device in operable contact with the test probe. The spectrum capturing device is configured to (i) collect and arrange frequency data measured by the test probe for the test signal, the return signal, and a standing wave created by the sum of the broadband data signal and the return signal, (ii) determine the voltage VSWR of the standing wave, and (iii) calculate a line loss from the VSWR.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation-in-part of U.S. patent application Ser. No. 15 / 376,375, filed Dec. 12, 2016, which claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 62 / 318,871, filed Apr. 6, 2016, and also to U.S. Provisional Patent Application Ser. No. 62 / 327,199, filed Apr. 25, 2016, the disclosures of all of which are herein incorporated by reference in their entirety. This application further claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 62 / 354,945, filed Jun. 27, 2016, the disclosure of which is also herein incorporated by reference in its entirety.BACKGROUND[0002]The field of the disclosure relates generally to data transmission systems, and more particularly, to attenuation testing on data transmission lines.[0003]In conventional data transmission systems, two impedance mismatches can create an echo tunnel on a transmission line, such as a cable line. A receiv...

AI Technical Summary

Benefits of technology

Enables accurate detection and location of single reflections and line defects on in-service data transmission lines, improving the ability to diagnose issues such as water damage, stress fractures, and other mechanical damage without disrupting the service, and providing a pass / fail indicator for line quality.

Problems solved by technology

It is therefore difficult, in conventional data transmission systems, to discover line defects, such as loose fittings and radial cracks, where an echo tunnel is not formed because only one impedance mismatch is encountered.

This problem is rendered more difficult due to the fact that time domain reflectometer (TDR) test equipment cannot be used on in-service cable plant.

Additionally, conventional cable operators experience a problem with aging cable lines that, over time, experience a variety of faults.

Other faults, such as water seeping into the cable, will increase signal attenuation through the cable, even if the seepage only sometimes produces reflections.

One conventional solution utilizes adaptive equalizers to compensate for reflections that are not too significant, but this solution does not address situations where the reflections are severe.

Moreover, flat signal attenuation experiences an additional noise problem due to low signal level pushing the desired signal into a noise floor.

This solution is not implemented on an in-service line.

That is, the line must be checked for faults due to problems such as water damage, stress fractures, corrosion, bad connectors, animal chews, or other mechanical damage.

The line may have excessive attenuation, reflections, or both.

This conventional solution also inconveniently requires active measurement equipment at both ends of the line.

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