we know not what we do!
Mike Gilmore
Mike Gilmore
Mike Gilmore Senior Partner, The Cabling Partnership
Managing Director e-Ready Building Standards Activities e-mail: [email protected] Mobile: +44 (0) 7860 110563 Member:
ISO/IEC JTC1 SC25 WG3: Generic Cabling ISO/IEC JTC1 SC25 Project Team: SOHO
Convenor:
ISO/IEC JTC1 SC25 WG3 IPTG: Industrial Premises Cabling Convenor:
CENELEC TC215 WG1: IT Cabling
CENELEC TC215 WG1 PT Industrial Premises Cabling Secretary:
CENELEC TC215 WG1 PT Data Centre Cabling Chairman:
BSI TCT7/-/1: IT Cabling
BSI TCT7/-/3: IT Cabling Support Group Technical and Standards Director:
The Measurement of Links
Link measurements Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connections Length Optical fibreAttenuation/insertion loss
Installed component measurements Link (physical)
The Measurement of Channels
Channel (physical) T Transceiver R R T TransceiverChannel (optical performance)
Channels measurements Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connections Length Optical fibre
Attenuation/insertion loss Length
Propagation delay
The Measurement of Channels
Channel (physical) T Transceiver R R T TransceiverChannel (optical performance)
Channels measurements Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connections Length Optical fibre
Attenuation/insertion loss
Length Propagation delay
Measurement Errors - Interface Connections
Link measurements Attenuation/insertion loss Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connections Length Optical fibreInstalled component measurements Channels measurements Attenuation/insertion loss Length Propagation delay MEASUREMENT ERROR due to INTERFACE CONNECTIONS MEASUREMENT ERROR due to INTERFACE CONNECTIONS
Measurement Errors - LMD
Link measurements Attenuation/insertion loss Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connectionsLength Optical fibre
Installed component measurements Channels measurements Attenuation/insertion loss Length Propagation delay MEASUREMENT ERROR due to
LAUNCHED MODAL DISTRIBUTION (MMF)
MEASUREMENT ERROR due to
LAUNCHED MODAL DISTRIBUTION (MMF)
Statistical Behaviour of Connecting Hardware
LS S Connection AT measurement P1 PM D LS S Reference measurement P0 PM D A T A LS S Connection BT measurement P1 PM D LS S Reference measurement P0 PM D B T B LS S Connection CT measurement P1 PM D LS S Reference measurement P0 PM D C T C AT BT CTStatistical Behaviour of Connecting Hardware
Multimode OF Singlemode OF All Attenuation (dB max) 95%<0,5dB 100%<0,75 dB Wavelength ISO/IEC 11801 (2002) and EN 50173-1Conventional Test Methods
Reference measurement P0 LS S D PM Launch cord LS SLaunch cord Test measurement P1
PM D Tail cord Link Measured loss LINK LS S
Launch cord Test measurement P1
PM D Tail cord Channel
LS S
Launch cord Reference measurement
P0 PM D Tail cord Dummy cord Measured loss CHANNEL
Interface Measurement Error
Frequency Chart .000 .057 .114 .171 .228 0 57 114 171 228 0.00 1.88 3.75 5.63 7.50 1,000 Trials 0 OutliersForecast: One Connection
Frequency Chart .000 .041 .082 .122 .163 0 40.75 81.5 122.2 163 0.00 1.88 3.75 5.63 7.50 1,000 Trials 0 Outliers
Forecast: Two Connections
0<99.8%<0.75
Improving Interface Error for LSPM
Launch cord Dummy cord Tail cord
Launch cord Dummy cord Tail cord Terminations made with sized-ferrule SM components Terminations made with sized-ferrule SM components against reference cords MMF
Single Test LSPM Method
LS S
Launch cord Test measurement
P1 PM D Tail cord Cabling under test
LS S
Launch cord Reference measurement P0
PM D Tail cord Dummy cord
Measured loss
Cabling under test Tail cord Reference measurement P0 Launch cord Dummy cord Measured loss LSPM S D LSPM S D LSPM D S Reference measurement P1 Test measurement P1
Launch cord Tail cord
Test measurement P1 Launch cord LSPM D S Tail cord Tail cord Launch cord
The Impact of Modes on MMF Testing
n1(r)
n2
The number of modes = function {(N.A x core diameter)/(λλλλ)}
Mode Group 1 Modes Σ Σ Σ Σ Modes 2 2 19 380 38 2 6 4 3 12 6 4 20 8 5 30 10 6 42 12 7 56 14 8 72 16 9 90 18 10 110 20 11 132 22 12 156 24 13 182 26 14 210 28 15 240 30 16 272 32 17 306 34 18 342 36 50/125 MMF @ 850nm Mode Group 1 Modes Σ Σ Σ Σ Modes 2 2 2 6 4 3 12 6 4 20 8 5 30 10 6 42 12 7 56 14 8 72 16 9 90 18 10 110 20 11 132 22 12 156 24 50/125 MMF @ 1300nm Mode Group 1 Modes Σ Σ Σ Σ Modes 2 2 19 380 38 15 240 30 16 272 32 17 306 34 18 342 36 62,5/125 MMF @ 850nm Mode Group 1 Modes Σ Σ Σ Σ Modes 2 2 62,5/125 MMF @ 1300nm 24 600 48 20 420 40 21 462 42 22 506 44 23 552 46 25 26 27 28 29 30 31 58 50 52 54 56 60 62 812 650 702 756 870 930 992 19 380 38 13 182 26 14 210 28 15 240 30 16 272 32 17 306 34 18 342 36 ... ... ... ... ... ...
Mode Groups and Power Distribution
n1(r)
n2
The number of modes = function {(N.A x core diameter)/(λλλλ)}
Mode Group 1 Modes Σ Σ Σ Σ Modes 2 2 19 380 38 2 6 4 3 12 6 4 20 8 5 30 10 6 42 12 7 56 14 8 72 16 9 90 18 10 110 20 11 132 22 12 156 24 13 182 26 14 210 28 15 240 30 16 272 32 17 306 34 18 342 36 50/125 MMF @ 850nm Mode Group 1 Modes Σ Σ Σ Σ Modes 2 2 2 6 4 3 12 6 4 20 8 5 30 10 6 42 12 7 56 14 8 72 16 9 90 18 10 110 20 11 132 22 12 156 24 50/125 MMF @ 1300nm 0 0.2 0.4 0.6 0.8 1
Mode Group (normalised)
Mode Transfer Function
Mode Power Distribution (normalised)
Cumulative Power Distribution (normalised)
Launched Modal Distribution - LMD
0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 OVERFILLED LAUNCH “EQUILIBRIUM” STYLE LAUNCH VCSEL LAUNCHX-axis = Mode Group (normalised)
Mode Transfer Function Mode Power Distribution (normalised) Cumulative Power Distribution (normalised)
Coupled Power Ratio - MMF
LS S MMF/125 cord CPR measurement P1 PM D SMF cord 5 µµµµm @ 850 nm 9 µµµµm @ 1300 nm LS SMMF/125 cord Reference measurement P0 PM D 20-21 dB 50/125 MMF @ 850nm 0.8-1% 16-17 dB 50/125 MMF @ 1300nm 2.0-2.5% 25-26 dB 62.5/125 MMF @ 850nm 0.25-0.32% 21-22 dB 62.5/125 MMF @ 1300nm 0.63%-0.8%
HOW TO OBTAIN THE CORRECT CPR
The right light source Modify the launch using: Mandrels? Mode conditioning?
Standardised MPD
HOW TO OBTAIN THE CORRECT MPD
The right light source Modify the launch using: Mandrels? Mode conditioning? 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0
Normalised mode group Normalised power
Allowed distribution must not enter shaded areas
Mandrels?
0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 0 0.2 0.4 0.6 0.8 1 62.5/125 Medium NA sourceMode Group (normalised)
Mode Transfer Function Mode Power Distribution (normalised) Cumulative Power Distribution (normalised) 62.5/125 High NA source 62.5/125 Low NA source Mode Transfer Function Mode Power Distribution (normalised) Cumulative Power Distribution (normalised) WITH MANDRELS NO MANDRELS
FIA-Sponsored Mode Conditioning Cords
Output CPR vs Input CPR
24 24.2 24.4 24.6 24.8 25 25.2 25.4 25.6 25.8 0 5 10 15 20 25 30 input CPR, dB o u tp u t CP R, d BNew Test Systems - I
Link measurements Attenuation/insertion loss Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connections Length Optical fibreInstalled component measurements Channels measurements Attenuation/insertion loss Length Propagation delay MEASUREMENT ERROR due to INTERFACE CONNECTIONS MEASUREMENT ERROR due to INTERFACE CONNECTIONS
Re
duc
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Re
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New Test Systems - II
Link measurements Attenuation/insertion loss Attenuation/ insertion loss Return loss Interfaces Embedded connections Optical fibre Interfaces Embedded connectionsLength Optical fibre
Installed component measurements Channels measurements Attenuation/insertion loss Length Propagation delay MEASUREMENT ERROR due to
LAUNCHED MODAL DISTRIBUTION (MMF)
MEASUREMENT ERROR due to
LAUNCHED MODAL DISTRIBUTION (MMF)
Re
mo
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Re
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Universal Test Results
Standardised LMD and low error connections
offers
universality of test equipment and comparison of results
