Why Signal Leakage, Why Now?

Ingress has been the single largest thorn in the side of cable operators since the advent of CATV plants, only to be aggravated by the introduction of two-way services.  Despite decades of innovation, the silver bullet solution to fully address this problem remains elusive.

Why Ingress Is Such a Challenge:

  • Upstream Ingress is Cumulative (The Funnel Effect) – many small ingress sources are additive as the many branches of the typical tree-and-branch architecture combine into a common trunk resulting in a much larger end effect. Just one shielding weakness can take down services for an entire node if near a noise source.  It is also impossible to remotely pinpoint where specific service-impacting upstream ingress is entering the plant.
  • Ingress is Often Intermittent – Nothing is more frustrating than chasing an ingress issue for hours only to have it disappear. Did you fix a major shielding weakness allowing noise sources in or did the noise source go away (streetlights switched off, someone finished their treadmill workout, …)?  Each time the noise source switches back on it is another mad scramble to find where it is getting into the plant before it disappears again.

Experienced technicians have become quite efficient at using divide and conquer techniques to find and fix ingress sources, but these common field practices create as much customer dissatisfaction and potentially churn as the ingress problems themselves.  Opening amp housings lets in massive ingress during testing, and pulling pads (yes, some of your Tech’s ARE pulling pads) can drop service for entire plant segments.  Sometimes the cure is worse than the disease!  Perhaps it is time to think differently about this problem.

Why Signal Leakage

Cable operators can’t control the external noise sources that impact their services, but they can control the shielding weaknesses letting the noise in.  That is where signal leakage techniques shine – enabling fast, efficient localization of plant shielding weaknesses in a 100% non-impacting process.

  • Precise localization of shielding weaknesses – no funnel effect!
  • Find shielding weaknesses any time – no intermittency in noise sources
  • No service impact while troubleshooting – leakage is a touchless process

Getting Started Is Simple

Getting started can be as simple as outfitting your Maintenance Tech’s with leakage meters to detect shielding weaknesses where OFDM is leaking from the network.

From this point you can:

  • Add leakage taggers allowing detection of smaller leaks anywhere across your spectrum.
  • Add mobile mounts to trucks enabling continuous leak detection as the Tech’s drive to jobs
  • Add a centralized collection server enabling collection, analysis, and prioritization of which leaks to address first network-wide
  • Integrate this centralized leak data with PNM, QoE, and return path monitoring data delivering the most complete picture of plant integrity enabling optimal targeting maintenance tasks for maximum return on investment.

Tight plants simply perform better, and while not every leak fixed will immediately improve SNR or reduce codeword errors, over time the benefits of a tight plant will be tangible on both your bottom line and your subscriber’s satisfaction.


Learn more about VIAVI Cable Signal Leakage

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