Segmentation HFC Systems

8/6/2019 Segmentation HFC Systems

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Segmentation of HFC Systems.Segmentation of HFC Systems.

To: SCTETo: SCTE, Ontario group., Ontario group.

Ottawa, 13Ottawa, 13thth

of May 2004of May 2004

By: Andy Lamarre, Dir. Eng.By: Andy Lamarre, Dir. Eng.

Trispec Communications Inc.Trispec Communications Inc.

SCTE, Senior member.SCTE, Senior member.


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Why Segment the Network.Why Segment the Network.

Increase Forward Bandwidth.Increase Forward Bandwidth.

Reduce Home Passed Ratios.Reduce Home Passed Ratios.

Faster and secure INTERNET delivery.Faster and secure INTERNET delivery.

Reduce NOISE and DISTORTION on the Forward path.Reduce NOISE and DISTORTION on the Forward path.

Prepare your HFC network for IP transport.Prepare your HFC network for IP transport.

Reduce NOISE and DISTORTION on the Return path.Reduce NOISE and DISTORTION on the Return path.

Assure Video on Demand delivery.Assure Video on Demand delivery.


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Lets have a look at some of todays availableLets have a look at some of todays available

methodologies to:methodologies to:

Increase Bandwidth.Increase Bandwidth.

Deliver better Signal quality.Deliver better Signal quality.

Reduce Homes Passed Ratio.Reduce Homes Passed Ratio.

Improve transmission specifications.Improve transmission specifications.


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By replacing RF Amplifiers with better DiplexBy replacing RF Amplifiers with better Diplex--Filters.Filters.

55 -- 30 / 4830 / 48 550 MHz550 MHz

First diplexFirst diplex--filters available in the CATV industry and no longer practical tfilters available in the CATV industry and no longer practical today.oday.

55 -- 40 / 5240 / 52 -- 870 MHz870 MHz

The DiplexThe Diplex--Filters most commonly used today.Filters most commonly used today.

55 -- 42 / 5442 / 54 870 MHz870 MHzProblems with these diplexProblems with these diplex--filters with signals carried below 54.0 MHz,filters with signals carried below 54.0 MHz,

signals for Sweep systems and Status Monitoring, etc.signals for Sweep systems and Status Monitoring, etc.

55 65 / 8565 / 85 -- 870 MHz870 MHz

DiplexDiplex--filters used in Europe, but could also be used in North America.filters used in Europe, but could also be used in North America.

These diplexThese diplex--filters will cause you to losefilters will cause you to lose 30 MHz30 MHz on Forward Transmission,on Forward Transmission,

(ch:2 to ch: 6), but will increase the Return Path by(ch:2 to ch: 6), but will increase the Return Path by 25 MHz.25 MHz.

Requires CRTC approval in Canada.Requires CRTC approval in Canada.


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By replacing existing RF Amplifiers:By replacing existing RF Amplifiers:

Push pull amplifiers;Push pull amplifiers;

Have a 48.5 dBmV maximum output level.Have a 48.5 dBmV maximum output level.

Power Doubling amplifiers;Power Doubling amplifiers;


GaAs (Gallium Arsenide) amplifiers;GaAs (Gallium Arsenide) amplifiers;


Above specifications with 80 ANALOG Signals and 350 MHz of DigiAbove specifications with 80 ANALOG Signals and 350 MHz of Digital Signal at 6.0 dB lower.tal Signal at 6.0 dB lower.

Higher output level guarantee better quality signal before DISTOHigher output level guarantee better quality signal before DISTORTION appears.RTION appears.


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Above measured with 0.4 dB loss per km.Above measured with 0.4 dB loss per km.

By upgrading Forward 1310 nm optical transmitters.By upgrading Forward 1310 nm optical transmitters.

Available frequencies today:Available frequencies today:

750, 870 and 1000 MHz.750, 870 and 1000 MHz.

Available power:Available power:

4 dB reach (10 km) between TX and NODE.4 dB reach (10 km) between TX and NODE.

5 dB reach (12.5 km) .5 dB reach (12.5 km) .

6 dB reach (15 km) .6 dB reach (15 km) .





Should always try to hit the NODE with 0.0 to + 2.0 dBm forShould always try to hit the NODE with 0.0 to + 2.0 dBm for

best Carrier to Noise and Distortion specifications.best Carrier to Noise and Distortion specifications.


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With optical couplers, one (1) 1550 nm optical transmitter is caWith optical couplers, one (1) 1550 nm optical transmitter is capable ofpable of

feeding many NODES.feeding many NODES.

By upgrading to 1550 nm forward optical transmitters.By upgrading to 1550 nm forward optical transmitters.

Available frequency 750, 870 and 1,000 MHzAvailable frequency 750, 870 and 1,000 MHz

Single or Dual output transmitter.Single or Dual output transmitter.

Output level between 7.0 to 8.0 dBm.Output level between 7.0 to 8.0 dBm.

Should always look for equipment with a 16 dB SBS control.Should always look for equipment with a 16 dB SBS control.

(Stimulated Brillouin Scattering)(Stimulated Brillouin Scattering)

Must be coupled with an EDFA, remembering the maximum powerMust be coupled with an EDFA, remembering the maximum power

introduced in the fibre is + 16.0 dBm.introduced in the fibre is + 16.0 dBm.

NODE usually requires an input betweenNODE usually requires an input between -- 2.0 to + 2.0 dBm, where2.0 to + 2.0 dBm, where

0.0 dBm should be the input target for a good DISTORTION and C/N0.0 dBm should be the input target for a good DISTORTION and C/N level.level.

With the proper use of EDFAs, the maximum length of a 1550 nm sWith the proper use of EDFAs, the maximum length of a 1550 nm systemystem

can be around 130 km, between the optical TX and the last NODE.can be around 130 km, between the optical TX and the last NODE.


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Return Optical receivers are capable of an input.Return Optical receivers are capable of an input.Between +0.0 toBetween +0.0 to --14.0 /14.0 / --16.0 dBm.16.0 dBm.

By Replacing 1310 nm optical Return transmitters.By Replacing 1310 nm optical Return transmitters.

Available frequencies: 5 to 200 MHz,Available frequencies: 5 to 200 MHz,

The RF portion will only pass the frequencies the RF Diplex FiltThe RF portion will only pass the frequencies the RF Diplex Filters will allow.ers will allow.

Available technologies today:Available technologies today:

Fabry PerotFabry Perot (FB)(FB)

Distributed FeedbackDistributed Feedback (DFB)(DFB)

Power available:Power available:

0.4mW (0.4mW (--4.0 dBm) FB, distance of 25 km.4.0 dBm) FB, distance of 25 km.

1.0mW (0.0 dBm) DFB, distance of 35 km.1.0mW (0.0 dBm) DFB, distance of 35 km.

2.0 mW ( 3.0 dBm) DFB, distance of 42.5 km.2.0 mW ( 3.0 dBm) DFB, distance of 42.5 km.

Above @ 0.4 dB loss per km withAbove @ 0.4 dB loss per km with14.0 dBm input at RX.14.0 dBm input at RX.


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Possibility of using EDFAs.Possibility of using EDFAs.With 16 and more ITU Wavelengths.With 16 and more ITU Wavelengths.

Must use MUX and DEMUX.Must use MUX and DEMUX.

Must be careful to keep the level at +/Must be careful to keep the level at +/-- 2.0 dB between ITU Wavelengths.2.0 dB between ITU Wavelengths.

Remembering, EDFAs output will change with the addition and remRemembering, EDFAs output will change with the addition and removaloval

of ITU Wavelength.of ITU Wavelength.

Installing TDM return 1550 nm optical transmitterInstalling TDM return 1550 nm optical transmitter..

TTimeime DDomainomain MMultiplexing.ultiplexing.

Available frequencies today:Available frequencies today: 5 to 200 MHz.5 to 200 MHz.

TDM available technologies today:TDM available technologies today:

Three (3) RF Return Input, Multiplexed @ 3.1 GbpsThree (3) RF Return Input, Multiplexed @ 3.1 Gbps

Four (4) RF Return Input, Multiplexed @ 4.2 GbpsFour (4) RF Return Input, Multiplexed @ 4.2 Gbps

Output level between 0.0 to + 8.0 dBmOutput level between 0.0 to + 8.0 dBm

ITU Wavelength available with the use of DWDM.ITU Wavelength available with the use of DWDM.

TDM optical receivers are capable of:TDM optical receivers are capable of:

Between +0.0 toBetween +0.0 to --18.0 dBm input, giving a 26.0 dB link at a single18.0 dBm input, giving a 26.0 dB link at a single

1550 nm ITU grid, without the use of EDFAs.1550 nm ITU grid, without the use of EDFAs.


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With Multi ITU Wavelengths, it might be time to have a look at uWith Multi ITU Wavelengths, it might be time to have a look at usingsing

EDFAs with AGC control, this will help give a constant output lEDFAs with AGC control, this will help give a constant output level.evel.

An important note on 1550 nm EDFAs and multi Wavelengths.An important note on 1550 nm EDFAs and multi Wavelengths.

AA 16.0 dBm16.0 dBm EDFA with one wavelength will have its outputEDFA with one wavelength will have its output

reduced to:reduced to:

13.0 dBm13.0 dBm with two (2) ITU Wavelengths,with two (2) ITU Wavelengths,

10.0 dBm10.0 dBm with four (4) ITU Wavelengths,with four (4) ITU Wavelengths,

7.0 dBm7.0 dBm with eight (8) ITU Wavelengths,with eight (8) ITU Wavelengths,

4.0 dBm4.0 dBm with sixteen (16) ITU Wavelengths.with sixteen (16) ITU Wavelengths.

EDFAs are available with: 13, 16, 18, 19, 20, 21 and 22 dBm outEDFAs are available with: 13, 16, 18, 19, 20, 21 and 22 dBm outputs.puts.


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Remember higher QAM levels will require a cleaner signal.Remember higher QAM levels will require a cleaner signal.

By using better QAM technologies.By using better QAM technologies.

On the forward path:On the forward path:

Move from 64 QAM to 256 QAM transmission schemes.Move from 64 QAM to 256 QAM transmission schemes.

Have a look at 1,024 QAM, soon to be available.Have a look at 1,024 QAM, soon to be available.

On the return path:On the return path:

With DOCSIS 1.0, use the maximum bandwidth of 3.2 MHz and goWith DOCSIS 1.0, use the maximum bandwidth of 3.2 MHz and go

from QPSK to 16 QAM.from QPSK to 16 QAM.

With DOCSIS 2.0, use the full 6.4 MHz bandwidth.With DOCSIS 2.0, use the full 6.4 MHz bandwidth.

With DOCSIS 2.0, use 128 QAM at a 30.0 Mbps throughput.With DOCSIS 2.0, use 128 QAM at a 30.0 Mbps throughput.


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NODEH.E.H.E.

Todays HFC distribution sectionTodays HFC distribution section

.

.

Fiber sectionFiber section

15001500

ToTo

20002000subssubs

Coaxial systemCoaxial system


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NODENODE NODENODE NODENODE

H.E.H.E.

66

Fibres RequiredFibres Required

By adding additional NODES in the original pocket, this will redBy adding additional NODES in the original pocket, this will reduce INGRESS Noiseuce INGRESS Noisein the return path and improve signal quality in the forward secin the return path and improve signal quality in the forward section.tion.

More fibres will be required ifMore fibres will be required ifadditional NODE are installed.additional NODE are installed.


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By installing NODES with a Dual Optical RX and Dual Analog ReturBy installing NODES with a Dual Optical RX and Dual Analog Return TXn TX

H.E.H.E. 44Fibres RequiredFibres Required

50 to 870 MHz50 to 870 MHz

5 to 40 MHz5 to 40 MHz

50 to 870 MHz50 to 870 MHz



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By installing NODES with a Dual Optical RX and a Digital ReturnBy installing NODES with a Dual Optical RX and a Digital Return TXTX

Operating at 3.1 Gbps with 3 Return sections.Operating at 3.1 Gbps with 3 Return sections.

H.E.H.E.


50 to 870 MHz50 to 870 MHz


50 to 870 MHz50 to 870 MHz


33


If a 4th RF sections is required,If a 4th RF sections is required,

select for lowest number of subsselect for lowest number of subs

on two return path.on two return path.

TDMTDM

TransmitterTransmitter


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50 to 870 MHz50 to 870 MHz

H.E.H.E.

By installing NODES with a Dual Optical RX and Digital Return TXBy installing NODES with a Dual Optical RX and Digital Return TXOperating at 4.2 Gbps with 4 Return section.Operating at 4.2 Gbps with 4 Return section.



33


50 to 870 MHz50 to 870 MHz



TDMTDM

TransmitterTransmitter


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50 to 870 MHz50 to 870 MHz


50 to 870 MHz50 to 870 MHz


50 to 870 MHz50 to 870 MHz


50 to 870 MHz50 to 870 MHz


H.E.H.E.88


By installing NODES with Four Optical RXs and Four Analog ReturBy installing NODES with Four Optical RXs and Four Analog Return TXsn TXs


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By installing 1550 nm equipment, EDFAs and optical couplers.By installing 1550 nm equipment, EDFAs and optical couplers.

12 km3.0 dB

7.8

1.4IN

11.0

0.8IN

9.8 km2.45 dB

14.0

0.5IN16.2 km4.05 dB

16 km4.0 dB

11.0

0.8

IN

16 dBEDFA

NODE

2

NODE3

NODE4

NODE

5

NODE

1

1550TX

18 km4.5 dB

16 dBEDFA

46 dBmV45 "

44 "43 "42 "41 "40 "39 "38 "37 "35 "34 "

750 870 MHz55045030050

Forward output for all NODES.Forward output for all NODES.


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12 km3.0 dB

5.8

1.9IN

7.6

1.3IN

9.8 km2.45 dB

11.0

0.8IN

16.2 km4.05 dB

16 km4.0 dB

22.1

0.3

IN

IN

13 dBEDFAOutput:

6 dBm

+8.0 dBm

+8.0 dBm+8.0 dBm+8.0 dBm

+8.0 dBm

18.0 km

4.5 dB

1= -16.82= -15.03= -16.94= -17.05= -16-66= Spare

NODE1

NODE2

NODE3

NODE4

NODE

5

DEMUX

19.0

0.4

IN

Output: 1

Output: 3Output: 2Digital

RX

Reducing NOISE and INGRESS on the return path by usingReducing NOISE and INGRESS on the return path by using

TDM technology. With one (1) fiber with five (5) NODES.TDM technology. With one (1) fiber with five (5) NODES.

Test PointTest Point

OTDROTDR

Actual return signalActual return signal

from each NODEfrom each NODE


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A biA bi--directional 1550 nm system, using EDFA and optical couplers.directional 1550 nm system, using EDFA and optical couplers.

12 km3.0 dB9.8 km2.45 dB16.2 km4.05 dB

16 km4.0 dB

16 dBEDFA

NODE2

NODE3

NODE4

NODE5

NODE1

1550TX

18 km

4.5 dB

16 dBEDFA

ReturnTest Point

In this example, we have upgraded a 72 km HFCIn this example, we have upgraded a 72 km HFC

system, using 1550 nm equipments in both fibressystem, using 1550 nm equipments in both fibres

which include 5 biwhich include 5 bi--directional NODES.directional NODES.


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One more consideration, to guarantee a clean return system, isOne more consideration, to guarantee a clean return system, is

by the installation of an INGRESS control system.by the installation of an INGRESS control system.

1

2

3

4

5

6

7

1 2

3

1-A

3-A

A

B

C

Headend

= Forward QPSK.= Forward QPSK.

1 = ClearPath= ClearPath

= INGRESS= INGRESS

Since INGRESS are sometimes very hard and long to find, anSince INGRESS are sometimes very hard and long to find, an

INGRESS CONTROL system is the best option to help you locateINGRESS CONTROL system is the best option to help you locateproblemproblem area and assure a clean return system.area and assure a clean return system.

INGRESS control switches can reduce or remove unwanted returnINGRESS control switches can reduce or remove unwanted return

signals, leaving the rest of the System fully operational.signals, leaving the rest of the System fully operational.


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One more way to insure a good quality signal on the return path,One more way to insure a good quality signal on the return path, is tois to

equip your HFC system with a Return status monitoring system.equip your HFC system with a Return status monitoring system.

The system should be able to provide a Local or IP communicatiThe system should be able to provide a Local or IP communications andons and

should be able to call technicians and managers when INGRESS appshould be able to call technicians and managers when INGRESS appears.ears.

5

MHz

40

MHz

50-860 MHz

5-200 MHz

FSKmodulation

52 MHz

fiber optic

9580 SST

5

MHz

40

MHz

MHz

5

MHz

40

Localor

IP Connection

5

MHz

40

Alarm.Alarm.

Require attention.Require attention.NormalNormal


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LOOK TV.LOOK TV.

Digital Television Signal in one direction.Digital Television Signal in one direction.

Trying to deliver biTrying to deliver bi--directional INTERNET.directional INTERNET.

Telephone companies.Telephone companies.

DSLAM technology, thru a twisted pair, capable of INTERNET serviDSLAM technology, thru a twisted pair, capable of INTERNET servicece

at 6 Mbps in both direction and Three (3) signals outputs, eachat 6 Mbps in both direction and Three (3) signals outputs, each

delivering a different analog TV signal.delivering a different analog TV signal.

Telephone companies.Telephone companies.

DSL, thru twisted pair, capable of 1.5 Gbps in both direction.DSL, thru twisted pair, capable of 1.5 Gbps in both direction.

Not fast enough to deliver good quality TV signal.Not fast enough to deliver good quality TV signal.

Express Vu andExpress Vu and Star Choice.Star Choice.

Digital Television Signal from satellite direct to the home.Digital Television Signal from satellite direct to the home.

So far these systems are unidirectional, with no INTERNET servicSo far these systems are unidirectional, with no INTERNET service.e.

Our competition:Our competition:


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CONCLUSION:CONCLUSION:With a well reengineered system,With a well reengineered system,

good maintenance and monitoring practices,good maintenance and monitoring practices,a INGRESS free return system,a INGRESS free return system,

youll be able to guarantee a full operating system at all timesyoull be able to guarantee a full operating system at all times..

ReturnReturn

System Flatness.System Flatness.

Ingress Level.Ingress Level.


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Thank you for yourThank you for yourATTENTION.ATTENTION.

This presentation can be sent to you by eThis presentation can be sent to you by e--mail @:mail @:

[email protected]@trispec.com

Segmentation HFC Systems

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