1 Networks and Optical Communications group – NOC WP#2: Simulation plans and progress

2 To define the applications for advanced network functionalities in terms of high data rate, low cost and power consumption. Define the device specifications of a waveguide phase modulator and an integrated MZI modulator. To define a device and system reference scenario that will be used for the performance evaluation of the developed components with respect to the identified applications. Milestone 2.1: Decision on implementation of devices based on the electro-optic modulation applications and material properties (M3) [Completed] Milestone 2.2: Definition of a system environment with respect to the network applications (M4) [completed] Deliverable 2.1: Definition of potential applications and system environment. First device specifications are issued (M6) [Completed] Deliverable 6.2: First report on SOFI exploitation activities (M12) [submitted] WP#2: Objectives [M1-M12]

3 Simulation progress and future plan Simulation Plan as per deliverable D2.1: –QPSK transmission at 56 Gbit/s and digital coherent detection –DP-QPSK transmission at 112 Gbit/s and digital coherent detection –Multi-channel QPSK-OFDM transmission Current activities: –100 Gbit/s OFDM systems –Subcarrier generation –OFFT filtering and direct detection –Performance optimization using iFFT circuits –QPSK/DQPSK transmission at 56 Gbit/s and digital coherent detection

4 Novel combline generation scheme Since wave frequency (10 GHz) Since wave frequency (2x 10GHz) Laser Advantage 1.Simple and cost-effective 2.Require drive voltage < ~Vpi = comb lines 3.Doesn’t require additional electrical diplexer or Modulators 4.Can generate more comb lines with larger drive voltages than Vpi VPI -Simulated comb-spectra Device specification : Differential MZM Vpi = 2V Drive voltage on arm1 with frequency f = 1.9 V Drive voltage on arm2 with frequency 2xf = 1.88 V Spectral flatness 0.9 dB

5 Electrical drive RF signals Initial Experimental results: with 10 GHz and 20 GHz RF clocks 20 GHz RF clocks With combined RF signal of 10 GHz and 20 GHz –8 comb-lines with unequal power ~2.5 dB –Drive amplitude was enough –Distorted clock signal of 20 GHz due to clock divider response –A better clock source would be required to achieve flatness < 1 dB

6 Dual Drive MZM Bias-2 Bias-1 Clock freq = 12.5 GHz Clock freq = 25 GHz Dual Drive MZM Bias-2 Bias-1 Clock freq = 25 GHz Clock freq = 12.5 GHz 6 dB MZM Bias-2 Bias-1 MZM Clock freq = 12.5 GHz 6 dB Comparison with other Comb-generation methods Dual-Drive MZM Our method Dual-drive MZM Using diplexer [5] Two MZM method [2] RF clock frequency Source required Basic  Second Harmonic X Basic  Second Harmonic X Basic  Drive Aplitudes => 0.96 => => 1.0 => = 1.17 = 2.47 => 0.5 => => 1.0 => = 1.0 = 0.35 Number of comb-lines 8  7  Peak optical power in comb-10 dBm X -7 dBm  -8.3 dBm  Spectral flatness (Max – Min)0.93 dB X0.84 dB X 0.51 dB  Extinction ratio (dB) 49.2  49.5  49.7  Inventory One DD-MZM  Two RF clock source RF Phase shifters One DD-MZM  Two RF clock source RF Phase shifters Diplexer RF Power splitter Two MZM X One RF clock source RF Phase shifters RF Power splitters High drive voltage amplifiers Complexity Simple  Moderate  Complex X Cost Cost effective  Costly  Relatively costly X

Gb/s 100 Gb/s OFDM signal Gbit/s Duobinary-OFDM  Data rates 100 Gbit/s  No of subcarrier = 8  Symbol rate = 12.5 Gbaud/s  Channel spacing = 100 GHz  Spectral efficiency (b/s/Hz) = Gbit/s Duobinary-OFDM Transmitter

8 Rx: 100 Gb/s Duobinary OFDM After 3x 40 km 0.01 Fiber span 40 km Subcarrier data signals are separated by OFFT Peak to average ratio is very large, which need to be minimized within ± 2dB System optimization is underway 100 Gbit/s Duobinary-OFDM Receiver with direct detection

9 Initial Result: 100 Gbit/s Duobinary-OFDM Possible to transmit signal up to 100 km fiber without using any dispersion compensating elements Fiber Length [km]

10 Performance optimization using optical iFFT circuit  For Stop band attenuation of 8 dB our scheme-> maintains rectangular spectrum and suppress residual frequency beyond OFDM channel bandwidth > 40 dB. Dramatically reduces the cross -talk

11 56Gbit/s DQPSK with direct detection DQPSK Transmitter DQPSK Receiver  Symbol rate = 28 Gs/s  Linewidth Tx = LO = 100 kHz  Extinction ratio = 25 dB  Tx power = 5 mW

12 56Gbit/s QPSK with coherent detection no DSP  Symbol rate = 28 Gs/s  Linewidth Tx = LO = 100 kHz  Extinction ratio = 25 dB  Tx power = 5 mW Rx= -35 BER 10-9

13 56Gbit/s QPSK with coherent detection with DSP  DSP for phase error correction enabled (parameter k=4)  Symbol rate = 28 Gs/s  Linewidth Tx = LO = 100 kHz  Extinction ratio = 25 dB  Tx power = 5 mW Rx= -36 BER 10-9

14 Maximum reach fiber length in Dispersion Managed system: for 56Gbit/s QPSK and DQPSK system QPSK transmission is BER upto 1280 km of fiber in dispersion managed system

15 Summary: Simulation Performed and Platform Built Combline generation schemes Simulation platform for system performance analysis of 100 Gbit/s Duobinary OFDM –Performance optimization of optical OFDM system using iFFT circuit Simulation platform built for system performance analysis of 56 Gbit/s DQPSK with direct detection Simulation platform built for transmission system performance analysis off 56Gbit/s coherent QPSK –Digital coherent receiver –Dual-polarization capability Publications 1.Arvind K. Mishra and Ioannis Tomkos, “A Novel Cost¬effective Combline Generation and Cross¬talk Mitigation in Optical OFDM Signal using Optical iFFT circuits”, Submitted to 18th International Conference on Telecommunications (ICT), 2011.

16 Performance of 56 Gbit/s QPSK with DSP without dispersion management system –WDM system Performance of 112 Gbit/s DP-QPSK without DSP with dispersion management system –Single channel –WDM system Performance of 112 Gbit/s DP-QPSK with DSP without dispersion management system –Single channel –WDM channel Validation of 100 Gbit/s duobinary OFDM results 100 Gbit/s QPSK OFDM Future Simulation Planned

17 M2.3 Development of a system and device simulation platform [M18] [in progress] M2.4 Derivation of the system-level specification of the developed hybrid components [M18]. [in progress] D2.2 Investigation of system-level specifications [M24] [in progress] D6.11 Intermediate report on recent achievements [M18] [in preparation] This report summarizes advances in the project for the general public. Precedence is given for publications in journals and on conferences or exploitation efforts. WP#2: Objectives [M13-M24]

18 Personal costs EURO Other Direct Costs (travels) EURO Indirect Costs (overheads) EURO Total cost EURO Requested EC Funding EURO Person Months (PMs)7.10 PMs in RTD and 0.35 PMs in Management Personal costs EURO Other Direct Costs (travels) EURO Indirect Costs (overheads) EURO Durable equipment Consumables Total cost EC contributions Person Months (PMs)14.0 PMs in RTD and 0.30 PMs in Management AIT financials for year 2010 Estimated AIT financials for year 2011 AIT Budget