Ross Saunders GM, Next-gen Transport Opnext Subsystems Inc. 100G Cost/Performance Optimization
Contents Historical vs Future Optical Transport Challenges What we did at 40G lessons learned Electronic and Photonic Integration 100G Design Architecture Summary 2
Optical Transport Historical Perspective Low loss silica MMF fibers GaAs lasers Bit Rat te 1T 100G 10G 1G 100M 10M 6M OOK 2km 1980 Technology Disruption Single mode fiber InGaAsP lasers EDFA WDM 45M OOK 20km 1985 155M OOK 20km 622M OOK 40km 1990 2.5G OOK 400km 1995 Hard FEC External modulation 10G OOK 0.2b/s/Hz 400km 2000 Advanced modulation schemes 40G PSBT DPSK 1b/s/Hz 1,200km 2005 Coherent Rx Soft FEC DSP for EDC 100G QPSK 2b/s/Hz 2,000km 2010 Rate adaptive MQAM Raman 2015 100G>1T MQAM 8b/s/Hz 40km > 4,000km Reference City of Light The Story of Fiber Optics Jeff Hecht, Oxford University Press, 1999 Year 3
40G Lessons Learned 40G market drivers were OC-768 PoS ports on IP routers and the need for spectral efficiency in the core Good business but did not meet cost points for deployment en masse Two phased 40G deployments irritated carriers CS-RZ/PSBT 1 st gen 40G, followed by CO/A-DPSK On line side, start-ups led the commercialization, a worry for large OEMs and carriers Mintera, Optium, CoreOptics and StrataLight Supply chain has been pretty fragmented chasing many modulation formats CS-RZ, PSBT, DPSK, DQPSK, PM-QPSK, OFDM 4
100G PM-QPSK Implementation Tx Block Diagram 4x25Gb/s inputs Grey TE MZI I π/2 CW laser PBS Grey Grey MZI Q MZI I π/2 I out TM Grey MZI Q Rx Block Diagram I in Local Oscillator 90º hybrid (phase/polarization diversity) Balanced Photodiode Balanced Photodiode Balanced Photodiode Balanced Photodiode ADC/DSP 4x25Gb/s outputs 5
Key Technology - Digital Coherent Receiver Adaptive Algorithm Error signal + Input distorted data A>D converter T T Adaptive Equalizer (n tap Digital FIR filter) T Σ(ADDER) T C 0 C 1 C 2 C 3 C 4 Decision Circuit Recovered output data 6
Electronic Integration 130nm SiGe for high speed mux ing and TIAs 132Gb/s (4x 32Gb/s) MUX speed 65nm CMOS for ADC/DSP/FEC modem system-on-a-chip >1Tb/s internal bus speed High development cost Low manufacturing cost High Speed SiGe MUX + High Density CMOS modem 7
100G Transmit Side Photonic Integration Photonic integration Opnext developed Mux OIF defined integrated transmit photonics 8
100G Receive Side Photonic Integration PHASE 1 GOLD BOX Photonic integration 90 deg hybrid A B Modem System-on-a-chip (4x ADC + DSP + FEC) EDFA LO ( itla ) C 90 deg hybrid D PHASE 1 GOLD BOX Opnext developed ADC/DSP/FEC ASIC OIF defined integrated receive photonics 9
1 st Generation Rx by U 2 T Coherent Detector Features: Symbol rate up to 32 GBaud/s Optimized for 100G DP-QPSK Full surface mount design with coplanar waveguide interface Integrated 90 Hybrids with linear balanced receiver technology Very low package footprint 37mm x 40mm x 6.6mm External SIG-PBS External LO-PBS Sig V PM-Fiber input Sig H Lo DC-Interface Lo DC-Interface RF-Interface 1mm pitch 10
100G Module Leadership 100G CFP module P802.3ba compliant 4x25G LAN WDM optical interface Power < 20W Footprint 125 x 86 mm Compliant to CFP MSA 100G DWDM module Must retrofit into existing DWDM infrastructure Power/footprint same as current 40G Price 2x current 40G Compliant to OIF 100G MSA Opnext leads the market in both 100G line and client modules 11
Summary 40G market fragmentation chasing too many modulation formats, should be avoided for 100G Carriers and OEMs don t want phased introduction 100G must meet the market requirements in 1 st design 100G coherent PM-QPSK format chosen and standardized at OIF to help focus supply chain and enable multi-sourcing Meets requirements but is a complex design Pushes the limit on electronics speed/complexity for ADC/DSP More complex optical design need photonic integration for cost/manufacturability/footprint reasons OIF standardization is helping create an eco-system and focusing investment capital Will see 100G component/module availability next year 12