tony holmes

Technical Training Seminar on

“Egress & Ingress Testing and Troubleshooting”

for CCTA Member Companies

August 25, 26 and 27, 2009 San Juan, Puerto Rico

Technical Training Seminar on

“Egress & Ingress Testing and Troubleshooting”

for CCTA Member Companies

August 25, 26 and 27, 2009 San Juan, Puerto Rico

Tony Holmes

Mario Sebastiani

Technical Training Presentation – CCTA 2009

Seminar SummarySeminar Summary

How the Egress and Ingress of unwanted signals in the forward and reverse plant behave

How they effect picture, data and voice quality

What to look for and how to fix it


Technical Training OutlineTechnical Training Outline Egress terminology What is egress Why do we test for egress What causes egress Egress characteristics Locating source of egress Signal Egress/Leakage Automation


Egress TerminologyEgress Terminology Leakage Radiation (Never Say!!!) µV/M Squelch Calibration Tagging (CT-2 or CT-3)


What is Egress/Leakage? What is Egress/Leakage?

Definition: – Undesired emission of signals out of HFC

networks – Egress is generally referred to as signal leakage


Egress & IngressEgress & Ingress

Ingress – RF or electrical energy

that enters the coaxial environment

Egress – RF signal leaking out

of the coaxial environment


Why do we test for leakage?Why do we test for leakage?


Reason #1 to Test for LeakageReason #1 to Test for Leakage

Meet FCC Compliance


Spectrum ChartSpectrum Chart

108MHz 137MHz

Aircraft Radio & Navigation

CH 98 CH 99 CH 14 CH 15 CH 16

Off-air

Cable


Cumulative Leakage Index (CLI)Cumulative Leakage Index (CLI) CLI is the net effect of the combination of all the

leaks in the system added together These cumulative leaks form an invisible cloud of

unwanted RF energy over the cable system


CLI Quarterly RulesCLI Quarterly Rules

Ride out 100% of system and log all leaks Log should include Date found and Date

fixed Documenting leakage levels isn’t required

for this drive out Actual practice for your system may vary!


CLI Annual RulesCLI Annual Rules

Ride out 75% of the oldest part of the system and log all leaks location and measured level

Must be performed within a reasonable period of time– Usually within 2 wks of due date


Required ActionsRequired Actions

All leaks 20µV/m must be logged and fixed Only leaks above 50 μV/m are used in CLI

calculation All measurements taken outside 108-137

MHz must be converted as if they were taken within the band


μV/MμV/M

Standard unit of measure for CLI

50 Ohm off air measurement Voltage developed in 1 meter of infinitely

thin section of wire submerged in a leakage field produces 1µV of energy


Acceptable Procedures for Leakage MeasurementAcceptable Procedures

for Leakage Measurement Use a calibrated halfwave dipole antenna Antenna must be elevated 3 meters off the

ground and positioned 3 meters from the leakage source

Antenna must be rotated 360º in the horizontal plane for maximum reading

CLI Fly-over


Reason #2 to Test for Leakage


Prevent Off-Air Interference


Off-Air InterferenceOff-Air Interference

Aeronautical & Aircraft Communications Amateur Communications Broadcast TV signals (Analog & Digital) Public and Emergency Communications Radio Mobile Communications

Technical Training Presentation – CCTA 2009 30

0

400

500

900

700

800

Off-Air Spectrum (forward path) Off-Air Spectrum (forward path)

Source: NTIA

Frequency in MHz




Improves System PerformanceReduces Repeat Service CallsLocate Physical problems


Common CausesCommon Causes 70% of all leakage is caused by problems

between the tap and entry to the house – Aging and environmental stress– Physical trauma to cables or connectors– Loose drop connectors– Inferior quality coaxial cable, passives, or

connectors– Loose hard line connectors


Other Causes of LeakageOther Causes of Leakage Improperly installed connectors Cracks in the trunk and feeder cables Animal chews Poorly-shielded drop cables Bad connectors at the taps Bad/loose port terminators Corroded connectors


Other Causes ContinuedOther Causes Continued Customer installed equipment Damaged amplifier housings Loose amplifier housing lids Broken tap ports Poor installation of splices and connectors Poorly-shielded customer premise equipment


Polarization AnglePolarization Angle Dipole

Monopole


Leakage Antennas-WhipLeakage Antennas-Whip


Leakage Antennas-DipoleLeakage Antennas-Dipole


Signal phasingSignal phasing


Standing Waves Standing Waves


Electrical NoiseElectrical Noise


Leakage Field StrengthLeakage Field Strength

HighestPotential

LowestPotential

Amp


Distance Correction Distance Correction

Reading x Distance (meters)

----------------------- = Corrected Reading

3


30 meters

3 meters20µVm

2 μVm

Patrolling for LeakagePatrolling for Leakage


Walking Out a Leakage AreaWalking Out a Leakage Area

5 – 10 meters


Leakage Detection ToolsLeakage Detection Tools


Seeker LiteSeeker Lite

Frequency Agile Leakage Detector

Built-in directional Antenna


How to Automate the Signal Leakage Process

How to Automate the Signal Leakage Process


Seeker GPS SystemSeeker GPS System

Seeker

BluetoothGPS Rx

SerialGPS Rx

LAWServer

MCA

LAWClient

BB-2


Seeker GPSSeeker GPS

Data StorageGPS EquippedWiFi Upload CapableMapQuest MappingServer Based

Data StorageGPS EquippedWiFi Upload CapableMapQuest MappingServer Based


Driving PreparationDriving Preparation

GPS– This icon is shown when the Seeker is placed in the

mobile mount and a GPS connection is established with the MCA. When the icon is not shown, the Seeker is not in the mobile mount or the GPS connection cannot be established with the MCA. If the icon blinks the MCA is connected to the GPS but the GPS does not have a good position fix


Seeker Data PathsSeeker Data Paths

Records uploaded to client

Leak Readings

Records

From GPS

WIFIPort 24007

Law

ServerPort 80

Third Party

Software

Other Applications


Work Order DistributionWork Order Distribution As leaks are uncovered, work orders will be

assigned – to technicians assigned to a specific leakage territory– or to the supervisor responsible for the area

Work order sent to designated person via email Techs can act on a leak reported via email, take

the appropriate pre- and post-fix snapshots, upload the data in the usual manner and the work orders will then close themselves out as the leaks are repaired


LAW MapLAW MapVersatile Map

Interface

Sort-able Leak List

Simple Work Order

Generation


Aerial ImageAerial Image


Work Order DistributionWork Order Distribution


Pre and Post-Fix MeasurementsPre and Post-Fix Measurements

Snapshot ModeUse the Seeker’s Snapshot button to access the snapshot mode


Demonstration

Egress/Leakage


Reason #4 to improve system quality

Reason #4 to improve system quality

Eliminates forward and return Ingress Prepares network for triple play deployments To increase plant performance and reliability


IngressIngress


Ingress on Analog ChannelsIngress on Analog Channels Lines in picture Ghosting Pay-per-view problems High speed data problems Interference with two-way radio services

using the same frequencies Repeat Service Calls


Ingress on Digital ChannelsIngress on Digital Channels

Macro Blocking (Tiling) Freeze Frame Picture and Sound go to black Robotic Voice Data Packet Loss or slower speeds Repeat Service Calls


Increased implementation of services requiring return path activation– If a system has egress it will most likely

have ingress– Ingress brings the viability of two-way

services into question–VoIP demands higher network reliability


Forward and Return Ingress

Troubleshooting Tools

Forward and Return Ingress

Troubleshooting Tools


QAM EVSQAM EVS Troubleshooting in-channel

ingress is easy with the QAM EVS mode– Typical ingress areas

Loose connector Tap plate loose Home wiring Sometimes

– CSO/CTB from an over driven amplifier


ConstellationConstellation

Good MER Poor MER


Digital signals work well until very close to the point of failure

Measurement of digital carriers critical to determine the system margin– Signal level– MER– BER

The BER Mode helps to find problems

BERBER


Demonstration

Interferences from VHF/UHF sources


Return Path Ingress Troubleshooting Techniques

Return Path Ingress Troubleshooting Techniques


Ingress Funnelling EffectIngress Funnelling Effect

Bi-directional system return path funnelling effect


ImpairmentsImpairments

Radio Communications and Transient Noise


Off-Air Spectrum (return path) Off-Air Spectrum (return path) 3MHz 9MHz

10MHz 40MHz30MHz

Source: NTIA


Ingress Mitigation TestIngress Mitigation Test This is a test where you can quickly check the

drop and home wiring for ingress

Set Ref level so as to not over-load

the meter Detector set for averaging RBW at 300 KHz 10 db/div Spectrum 5-108 MHz Use peak hold


Ingress Mitigation TestIngress Mitigation Test What you should see is NOTHING!

Just the noise floor


Ingress Mitigation TestIngress Mitigation Test

Look for ingress

by using the

“Peak Hold” function

Identify the problem by working

back towards the house


Ingress Mitigation TestIngress Mitigation Test


Using the I-Stop ProbeUsing the I-Stop Probe Press the button on the side of the probe

– If the ingress decreases by 4-6 dB when the button is depressed, the source of the ingress is farther from the node than you are

– Ingress that doesn't decrease is entering the system nearer to the node than you are.

The I-Stop Probe has little or no visible effect on forward path signals.


Preparing for Return Path Monitoring

Preparing for Return Path Monitoring


Network TopologyNetwork TopologyViewer II Clients

Viewer II Server

SST 9581 R4s

TCP 24007Live Spectrum

UDP 162SNMP Traps

TCP 80 and/or 443Viewer II Services

TCP 24007SST Data

UDP 161SNMP

UDP 24008Multicast on

224.1.2.3

UDP 24008Multicast on

224.1.2.3

9581 SSTReturn Path Analyzer


Monitoring ThresholdsMonitoring Thresholds Alarm threshold

information is stored in the 9581 SST

Five degrees of severity– For Ingress levels

Critical to Warning– For Outages

No Signal Warning Persistence Settings

– Authenticate alarm conditions

Traffic Curve– Identifies the frequency

and amplitude of carrier


Viewer II User InterfaceViewer II User Interface Components

– Status Tree– Incident Log– Alarm History– Node Reporting– Spectrum Display– ADIA Web View


Node Status TreeNode Status Tree Geography

– Groups nodes by City Headend Hubsite

Services– Groups nodes by

CMTS Blade


Incident LogIncident Log Displays Current Node Alarm

Events based on – SNMP Traps received by the

Guardian II Server Traps Originate in the 9581

SST based on – Alarm Threshold Violations – Persistence Settings

Displayed information is based on Status Tree Configuration, but typically includes– Node ID– Severity– Elapsed Time– Total Alarm Time


Alarm ManagementAlarm Management Prioritize Alarm Information

– Sorting Tools Organize alarm information into logical groupings for

managing service interruptions


Alarm TroubleshootingAlarm Troubleshooting To investigate alarm

conditions NOC operators can click on alarm events in the incident log– Brings up Spectrum view

with Alarm threshold and

ingress signature that caused the alarm event

Allows operator to correlate alarm data from other monitoring sources

Evaluate the effect of ingress on system services


ReportingReporting Node Service Report

– Returns Alarm Activity over user specified time periods and locations Provides correlation of service interruptions and

return path ingress events Identifies and prioritizes nodes in need of

maintenance– Selection Criteria

Alarm severity Number of nodes per location


Node Service ReportNode Service Report Summary View

– Includes selection criteria

– Lists nodes meeting selection criteria Grouped by location Number of nodes per

location or top X nodes Number of alarm

events per location


Spectrum DisplaySpectrum Display View

– Max/Min/Avg ingress spectra over reporting period

– Pass/Fail Threshold– Pass/Fail Tolerance

Ratio (dB) between threshold & ingress spectra


ADIA Web ViewADIA Web View Real time access to

headend ingress levels– Max/Min/Avg Traces– Markers with

Frequency Amplitude Delta


• Digital TV Transmitters• Return Path Ingress

Demonstration

Impairments from :


Response to Your Question!!!! s


Thank you-Gracias-Merci-Masha danki…

Thank you-Gracias-Merci-Masha danki…

Trilithic Applications [email protected] Tel: 800-344-2412----------------------------------------------------------------------

Incospec Communications Inc.Your Value Adder Trilithic Re-Seller for the Caribbean

Mario Sebastiani ([email protected])Bernard How ([email protected])

mailto:[email protected]



tony holmes

Documents

leakage signal leaking

leakage terminology

fcc leakage measurements

leakage amplitude necessary

signal leakagewhat

signal leakagehowever

egress older term

ccta member companiesaugust