f. vasey, cern on behalf of the versatile link project ... link... · 11 nov 2009...

11 Nov 2009 [email protected] 0

Versatile Link

Versatile Link Status Report

F. Vasey, CERN On Behalf of the Versatile Link Project

ATLAS Upgrade Week, November 2009


Versatile LinkSome Lessons learned from LHC

● System● …● Avoid use of single fibres and pigtails on detector● Do not allow excessive fibre-slack without corresponding management scheme.● Use ruggedized ribbon/fiber only.● Use balanced code● …

● QA● Develop and distribute tools which allow prototyping and testing● …

https://edms.cern.ch/document/882775/3.8

Concept for SLHC:Concept for SLHC:Pluggable Transceiver with electrical and optical connectionsPluggable Transceiver with electrical and optical connectionsCustomized for HEP environmentCustomized for HEP environmentStandard for test systems and off detectorStandard for test systems and off detector

https://edms.cern.ch/document/882775/3.8


Versatile LinkVersatile Link Project Description

● Optical Physical layer linking front- to back-end● Bidirectional, ~5Gbps● Versatile

● Multimode (850nm) and Singlemode (1310nm) versions● Point to Point and Point to Multipoint architectures

● Matching SLHC tracker environment, plus others● Joint Project (CERN, Fermilab, Oxford, SMU)

FE BE


Versatile Link

Optical Link Components

Point-to-Point architecture

FE BE


Versatile LinkTemplate TRx: SFP+ Transceiver

● Bi-directional Module with connector interface● Based upon an acknowledged standard● Work with Industrial partner early-on

● MM 850nm & SM 1310nm versions● Bitrate 2.5 – 10 Gbps● Fast access to hardware● Easy distribution to integrators● Customization in second step


Versatile Link

Backend Transceiver

A. ProsserFermilab

•Test Equipment Procured and Test Lab Configured•Evaluation of SFP+ 10 Gbps Transceivers @ 850 and 1310 nm (ongoing)•Evaluation of array components @850 and 1310nm (ongoing)•Partnership with Vendor for dense light engine Prototyping (ongoing)

SFP+ TRx

SNAP12 4TRxor 12Rx


Versatile Link

Optical Eye Pattern Analysis

PRBS Pattern Synchronization

Jitter Decomposition and Analysis

Digital Signal Analyzer

0 1 2 3 4 5 6 7 80.000

20.000

40.000

60.000

Jitter (Deterministic and Total (Avg))1310 nm, 3.125 Gbps, 8b/10b

Device NumberJi

tter (

ps)

0 1 2 3 4 5 6 7 80.00

200.00400.00600.00800.00

1000.00

Optical Modulation Amplitude (Stable)1310 nm, 3.125 Gbps, 8b/10b

Device Number

OM

A (u

W)

Backend Transceiver


Versatile LinkFront End Transceiver, Versatile-TRx

J. TroskaCERN

● Low Mass & Volume● Minimize material, avoid metals

● Non-magnetic, capable of operating in a magnetic field

● Requires replacement of ferrite bead used in laser bias network

● Bitrate determined by ASICs: 5 – 10 Gbps● 850nm and 1310nm flavours

TOSA

ROSA

GBLD

GBTIA

TOSA

ROSA

GBLD

TOSA

TOSA

TRx

2Tx


Versatile LinkFront-End TRx Testing roundup

● Test methods for evaluation of Transceivers in place, used routinely● Stable and well documented, having

been successfully used by several new team members

● Based on Laboratory instruments for eye diagram measurement and FPGA-based BERT for BER testing

● Have tried several methods for comparison of large amounts of data from different transceivers● Settled on Radar/Spider plots for ease of

visual interpretation


Versatile LinkFront-End TRx Packaging roundup

● Made good progress on testing GBLD and GBTIA, having designed optical test boards for both● GBLD shows marginal BW performance● GBTIA shows good functional performance

● Successfully designed and tested a number of test PCBs to gain experience with high-speed design and layout● Including magnetic-field tolerant laser bias-T● Developed functional model for laser diodes for

aid ASIC and PCB design

● Lower mass modified SFP+ module tested● Good performance achieved, no apparent

penalty from removing shielding


Versatile LinkFront-End TRx Radiation test roundup

● Carried out SEU test at fluxes beyond SLHC● 63MeV Protons at PSI, survey of a large number of devices (SM & MM)● Issues emerged for first time with Burst Errors● Clearly FEC must be employed at SLHC to ensure correct control

information received by front-ends● Carried out Total Fluence test to SLHC levels

● 20MeV neutrons at Louvain-la-Neuve Cyclotron, survey of a large number of devices (SM & MM)

● Good first test that shows the way to future testing● No clear best candidates emerged, most likely to survey SLHC

environment● Important to assess impact on overall system of using different device

types● E.g. absolute responsivity pre-irradiation for PINs, forward voltage and its

change in Lasers


Versatile LinkLasers irradiation Roundup


Versatile LinkPhotodiodes Irradiation Roundup


Versatile LinkPassive Components: total dose irradiation tests (SM)

● Status:● Gamma irradiation test carried out

to 700 kGy● 1 SM fibre @ 1310nm (SMF28)● SM PLCC splitter● SM LC-LC connectors

● Mechanical stress tests started with SMF28 fibre

● LHC-machine fiber irradiated to 1MGy: 5e-3 dB/m

SM- Corning SMF28

LHC 2007- Fujikura

T. HuffmanOxfordfibre


Versatile LinkPassive Components: total dose irradiation tests (MM)

MM

T = -23.30 C

T = ambient

● Status:● Gamma irradiation test carried out to

700 kGy● 4 MM fibres @ 850nm ● MM fused taper splitter ● SM LC-LC connectors

● Good first results obtained, identified 2 MM candidates

● Candidates irradiated in the cold● Plans:

● Irradiate to full SLHC doses at -25degC● Confirm MM fiber capacity


Versatile LinkSystem

● phase 1 workprogram: ● Development of P2P demonstrator based on commercial

transceivers.● Development of test bench(es) for components and systems● Development of test procedures.

● Status:● In house SFP+ carrier board has been designed and fabricated, running

up to 10Gbps. ● The test benches utilizing commercial Bit Error Rate Tester and utilizing

Stratix II GX based FPGA Bit Error Rate Tester are developed. ● The physical layer of the P2P network is verified. Its transmitter/receiver

waveforms, system BER and bath tub scan, as well as optical fiber link reach are characterized.

.

J. Ye, A. XiangSouthern Methodist University

5Gb/s optical loopback

SFP+ CarrierBoard


Versatile Link

16

System

BER vs. OMA, MM, 5Gbps, 2m, 150m, 1km

OMA of variousTRx vs. MM fiber length


Versatile LinkThe Versatile Link Project Roadmap

● Project proposal submitted to ATLAS and CMS SLHC upgrade steering groups in Nov07

● Project endorsed by ATLAS and CMS in early 2008● Kick-off Meeting 10 Apr 2008

● phase 1 proof of concept based on tentative specifications, partial tests and early prototypes●duration: 18 months, till 30 Sep 09●Phase 1 closeout meeting 20th Sept

● Phase 2: feasibility demonstration based on complete specifications and exhaustive tests on final prototypes●Oct 09 – Apr11

●Specs and procedures●Tests and Results●List of COTS components and suppliers●Test-systems and Prototype custom components

● Phase 3: specifications freeze, pre-production readiness, technico-commercial actions●Apr11 – Oct12


Versatile LinkComponents and Subassemblies

TOSA

ROSA

GBLD

GBTIA

TOSA

ROSA

ROSAGBTIA

Phase 1 (2008-09)Proof of concept

Phase 2 (2009-11)Feasibility


Versatile LinkCredits and References

● CERN● Jan Troska, Luis Amaral, Stefanos Dris, Alberto Jimenez Pacheco, Sarah Seif

el Nasr, Christophe Sigaud, Sergio Silva, Csaba Soos, Pavel Stejskal, François Vasey

● Fermilab● Alan Prosser, Mark Bowden, John Chramowicz

● Oxford, IPAS, CERN● Todd Huffman, K. Dunn, Alex Gerardin, Cigdem Issever, S.C. Lee, Z. Liang,

Z. Meng, A. Povey, Tony Weidberg● Southern Methodist University

● Jingbo Ye, Andie Liu, Kent Liu, Annie Xiang

● The radiation tolerance of specific optical fibres exposed to 650 kGy(Si) of ionizing radiation, 2009 JINST 4 P0710, published

● The Versatile Link, A Common Project For Super-LHC, JINST_002P_0709, to be published

● https://espace.cern.ch/project-versatile-link/public/default.aspx

f. vasey, cern on behalf of the versatile link project ... link... · 11 nov 2009...

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