A System's View of Metro and Regional Optical Networks
1. Cedric F. Lam ( [email_address] ) and Winston I. Way ( [email_address] ) SPIE Photonics West, Jan 29, 2009, San Jose, CA A System’s View of Metro and Regional Optical Networks
2.
3. Growing Broadband Applications and Technologies IPTV Nomadic Device Tele-presence Network Gaming Wi-Max xPON Backbone networks have to scale simultaneously!
9. Complexity vs. Benefits Pre-coded Data CDR Rx Modulation Transmitter Receiver OSNR (dB) @ 1e-3 , 42.7G NRZ-OOK NRZ-DPSK NRZ- DQPSK (no pol-mux) 16 dB 1 bit/symbol 14 dB 1 bit/symbol 15 dB 2 bits/symbol LD Data LD Pre-coded data-I LD Pre-coded Data-Q /2 CDR Rx 1-symbol delay CDR I-branch data Q-branch data CDR Rx 1-bit delay
10. Spectral Efficiency – Where Are We Today? M. Nakazawa: ECOC 2008 paper Tu.1.E.1 C-band: W=4THz , OSNR = 16dB (P/N=14.1dB @40Gb/s) Total Capacity (b/s) Spectral Efficiency (b/s/Hz) Shannon Limit 18.8T 4.7 Commercial Systems 10G x 40 (100GHz spacing) 400 G 0.1 10G x 80 (50GHz spacing) 800 G 0.2 40G x 40 (100GHz spacing) 1.6 T 0.4 40G x 80 (50GHz spacing) 3.2 T 0.8
11. EDFA C-band (Bandwidth = 4 THz) Utilization To support 50GHz spaced 100GE, we need to achieve C/W = 2 (b/s)/Hz 4x 100GbE 10G,100GHz space 10G, 50GHz space 10G, 12.5GHz space 8x 100GbE 32x 100GbE (125GHz space) C-band Gain + lowest fiber loss Maximizes P/N in Shannon capacity 80 x 100GbE (50GHz space) Commercially achieved
12. Metro / Regional WDM Network Architecture Metro/Regional WDM Transport Backbone PON LAN Wi-Max or LTE EDFA DCM ROADM DCM TRX TRX TRX
18. Non-linearity in PM-QPSK Oriol Bertran Pardo et. al: “Investigation of design options for overlaying 40Gb/s coherent PDM-QPSK channels over a 10Gb/s system infrastructure,” OFC 2008, paper OTuM 5 Performance significantly affected by XPM induced by neighboring 10G NRZ OOK signals.
19.
20. Cost Ratio Comparison of 40G/10G Technologies Source: H. Bosco, “Network Evolution to 40Gb/s”, ECOC 2008 Cost of 40G interface is significantly higher than that of 4x10G! DMC 40G DMC 100G OpNext Estimate
21. 40Gb/s Line Side Modulation Scheme Comparison DMC – 4x10G DMC – 2x20G PSBT (ODB) NRZ-DPSK RZ-DQPSK PM-QPSK Relative Cost Estimate -20% -10% 0% +20% +60% +75% CD Tolerance (ps/nm) 2000 500 320 100 200 35000 PMD Tolerance (ps) 10 (17) 10 2.1 2.5 8 30 OSNR Sensitivity (dB) 16.5 13.5 17.5 14 15 11 XPM Tolerance from 10G High High High High Low Low Applications Upgrade any 10G infra-structure + Greenfield Upgrade any 10G infra-structure + Greenfield Green Field Green Field Green Field Upgrade any 2.5G/10G infrastructure without 10G NRZ neighbors