1. Optical Packet Synchronizer ICE541 Concrete Mathematics 20022037 Kim jinah 20032001 Gang kwang wook Design of OPSy (Optical Packet Synchronizer)

2. Optical Packet Synchronizer ICE541 Concrete Mathematics What is OPSy (Optical Packet Synchronizer) ? In an asynchronous optical network system, each transmitter node sends out optical packets asynchronously. The electric control systems for switching these packets at an optical packet switching node(OPSw) are much simpler when incoming packets are aligned in a series of common time slots provided at the OPSw. This alignment call, which is also called packet synchronization, is a key technology for the development of OPSw, and it achieved using an optical packet synchronizers (OPSy). Introduction

3. Optical Packet Synchronizer ICE541 Concrete Mathematics coupler 2x2 Switch Signal(1550nm) circulator High dispersive fiber WC DFB LD (1540nm) WC DFB LD (1550nm) coupler 2x2 Switch Signal(1550nm) circulator High dispersive fiber WC DFB LD (1560nm) WC DFB LD (1550nm) Ch 1 Ch 2 2R regeneration Fiber Delay Loop Proposed Sync. system

4. Optical Packet Synchronizer ICE541 Concrete Mathematics Sync. System conditions Sync. System conditions - Testing 1 channel with 12 frequency - - Time slot & packet format · Time slot : 1024ns · Packet length : 896ns · Guard time : 128ns - DCF condition · Delay : 1.26ns/km · Dispersion : -90ps/nm km · Dispersion slope : 0.21ps/nm2km How’s it proceed - 12 optical packet generate randomly - Aligning Optical packets in ascending order - Calculating proper guard times each packets - Finding 12 optical packets delay times - Finding # of circulating fiber loop - Calculating the efficiency of signal channel on 12 optical packets Sync. System algorithm Time slot (1024ns) Packet length (896ns) Guard time (128ns) IEEE Photonic Technology Letter. Sep. 2002 Freq 1 Freq 2 Freq 3 Freq 12 …… ∆t 1 ∆t n Misalignment of packets (12 frequency)

5. Optical Packet Synchronizer ICE541 Concrete Mathematics Results of programming (using C Language) 12 channel frequency generate randomly 100496493410059641007968988953906973911 12 channel frequency in ascending order 906911934953964 968973988100410051007 Calculate 12 channel frequency’s appropriate guard time 118113907160 565136201917 Aligning 12 channel frequency’s 102420483072409651206144716881929216102401126412288 Finding 12 channel frequency’s delay times 1181137213831434156518062007219822892361025911281 Finding 12 channel frequency’s fiber loop circulating counts 0.008.5416.9425.3633.8642.4551.0059.5468.0076.4585.0393.60 Finding 12 channel frequency’s number of fiber looping 0816253342505968768593 Calculate the efficiency of signal channel on 12 channel frequencys : 99.87

6. Optical Packet Synchronizer ICE541 Concrete Mathematics Results of simulation (using VPI simulation tool and origin ) - Delay result of signal after passing DCF: 1km / 100km Delay : ~250ns

7. Optical Packet Synchronizer ICE541 Concrete Mathematics Results of simulation (using VPI simulation tool and originPro6.1 ) BER vs. Input power (“Optimum value:6dBm input power”) BER vs. SOA current (“Optimum value:200mA”)

8. Optical Packet Synchronizer ICE541 Concrete Mathematics : Problems of Dispersion and Distortion effect - Using some modified sync. System : Using filter and SOA 20km 50km 100km - Signal Distortion in DCF Results of simulation (using VPI simulation tool and originPro6.1 ) - Signal Dispersion in DCF 20km 50km 100km

9. Optical Packet Synchronizer ICE541 Concrete Mathematics - Modified Sync. System Results of simulation (using VPI simulation tool and originPro6.1 ) SOA Optical Filter coupler 2x2 switch Signal DCF - BER measurement (SOA) Input power : 5dBm SOA current : 200mA Loop delay time : 100ns With Bandpass filter

10. Optical Packet Synchronizer ICE541 Concrete Mathematics Input power : 5dBm SOA current : 200mA - BER measurement (No filter) Results of simulation (using VPI simulation tool and originPro6.1 ) - BER measurement (with filter)

11. Optical Packet Synchronizer ICE541 Concrete Mathematics - BER test (2.5Gb/s modulation) Results of simulation (using VPI simulation tool and originPro6.1 ) - BER test (10Gb/s modulation)

12. Optical Packet Synchronizer ICE541 Concrete Mathematics 1 st - 1.26ns/km delay for the DCF - timeslot of 1024ns - total fiber length = 92~km (very rough calculation) Very large volume !! Discussion 2 nd - Optimum power of 5dBm - Optimum SOA current of 200mA - With bandpass filiter (very rough calculation) BER of 10Gb/s modulation is not so bad But, BER of 2.5Gb/s modulation is so bad

13. Optical Packet Synchronizer ICE541 Concrete Mathematics After term project We adopted many algorithms such as random and sort to implement OPSy, although this topic is not directly related to Concrete Mathematics. Optical Network is coming up topic in Management field. Therefore, what we done is helpful to understand new technology and make more efficient decision. We focus on the studying and planning before mid-term presentation. After mid-term presentation, we focus on the real implementation. We finished implementing the Optical Packet Synchronizer. But We didn’t check up the efficiency of this algorithm. It will be our further works.