1. END

2. PRESENTATION CONTENTS THESIS TILTLE (1) PRESENTATION CONTENTS (1) INTRODUCTION (2) DESIGN PROCEDURES (2) DESIGN SPECIFICATION (1) DESIGN FACTOR (5) SOFTWARE FLOWCHARTS (17) SOFTWARE DESIGN EXAMPLE (6) PRESENTATION END END

3. OPTICAL FIBER SYSTEM DESIGN INTRODUCTION Advantages of Optical Fiber Communication –Extremely wide system bandwidth (LED provides more than 100MHz of BW, while LASER can deliver up to 10GHz). –Small size and weigh (human hair) –immunity to electromagnetic interference and cross talk. –Signal security –Low signal attenuation (compared to copper conductors) –unlimited supply (sand is the source of the optical fiber) –Reduced cost –Safety (no spark hazard or short circuit) END

4. OPTICAL FIBER SYSTEM DESIGN INTRODUCTION The Optical Fiber Communication System Components –The optical fiber system consists of three components : Transmitter Optical fiber Link Receiver –The Transmitter converts the input electric signal into an optical signal. –The Fiber Link carries the light signal and submit it to the receiver –The Receiver converts the optical signal back to it original form. END

5. OPTICAL FIBER SYSTEM DESIGN DESIGN PROCEDURES GRAPH AND CHART ASSISTED DESIGN This devised method is easy way to design an optical fiber system. However, this method is limited in use, since the it is applicable only to the system components made by the manufacture by whom those graphs and charts have been devised. FLOWCHART ASSISTED DESIGN This design method has been devised by some authors, the flowcharts are useful and can be utilized as a guide to the design of each subsystem independently of others. However, a major drawback of those flowcharts is that some of the design parameters in one subsystem are dependent on parameters in another subsystem. As an example, the selection of the spectral width and wavelength for the source affects the the dispersion and the attenuation of the fiber link as well as the spectral response of the detector. END

6. OPTICAL FIBER SYSTEM DESIGN DESIGN PROCEDURES COMEREHENSIVE FLOWCHART To override the mentioned drawbacks of the devised design procedures, a comprehensive flowchart is developed here to cover all the subsystems design considering most system parameters. SUB-SYSTEM FLOWCHARTS In addition, separated subsystem flowcharts are developed to allow the designer to design any part of the system alone. COMPUTER PROGRAM These flowcharts are implemented into a computer program where iterative processes are executed to reach to the best design combination according to predefined design parameters such as performance and cost. END

7. OPTICAL FIBER SYSTEM DESIGN DESIGN SPECIFICATION The usual specifications given to an optical fiber link designer are Data Rate (bit rate), Link Length, and Bit Error Rate (BER). Once these requirements are given, the designer must try various combination of the optical source, fiber, and detector to meet the power budget, bandwidth budget, and cost budget. END

8. OPTICAL FIBER SYSTEM DESIGN DESIGN FACTORS POWER BUDEGT The following parameters influence the power budget : Source output power (emitted power), P t Source to fiber coupling loss, P c Fiber’s attenuation, .L Joint loss, P j and Connector loss, P k Detector sensitivity, P r Power margin, P m P t = P c +  L + P j + P k + P r + P m where Pc: is the coupling losses,  L : is the attenuation, Pj : is the joint losses (=Nj*Sj, Nj=int(L/Lp)-1), Pk : is the connector loss (datasheet), Pr : is the detected power sensitivity), Pm : is the power margin (cover degradation, installation, temp.) 1 END

9. OPTICAL FIBER SYSTEM DESIGN DESIGN FACTORS BANDWIDTH BUDEGT The Bandwidth budget is affected by the dispersion in the fiber. The bandwidth budget can be calculated from the relationship of the system rise time shown below : where T t : is the total system rise time, T s : is the source rise time, T d : is the detector rise time. The value of system rise time should be less than or at least equal to the input pulse rise time. The input pulse rise time can be calculated as follows: 2 END

10. OPTICAL FIBER SYSTEM DESIGN DESIGN FACTORS BANDWIDTH BUDEGT (cont.) T p = 0.7*W p for [NRZ] T p = 0.35*W p for [RZ] where T p : is the input pulse rise time, W p : is the pulse width [W p = 1/B], where B : is the bit rate The source rise time, T s, and the detector rise time, T d, are normally given by the manufacture, but the fiber rise time T f is computed as follows: 1- if the BWF is given then 2 END

11. OPTICAL FIBER SYSTEM DESIGN DESIGN FACTORS BANDWIDTH BUDEGT (cont..) 2- if BWF is not given then, the T f can be computed from the dispersion as follows: where D : is the material dispersion coefficient L : is the fiber length  : is the source spectral width c : is the speed of light n1 : is the refractive index of the core  : is the relative refractive index 2 END

12. OPTICAL FIBER SYSTEM DESIGN DESIGN FACTORS COST BUDGET The following Cost Estimation Relationship (ER) is developed for fiber optics transmission systems; where COSTA : is the main cost factor L R : is the cost modifier to be adjusted according to the improvement technology (increasing with new development) L r : is the repeater spacing L : is the total fiber length B : is the Bandwidth in MHz For long haul fiber optics transmission system: 3 END

13. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS GENERAL FLOWCHART END

14. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS TRANSMITTER DB FLOWCHART BACK END

15. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS FIBER DB FLOWCHART BACK END

16. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS RECEIVER FLOWCHART BACK END

17. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS TRANSMITTER FLOWCHART BACK END

18. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS CABLE FLOWCHART BACK END

19. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS RECEIVER FLOWCHART BACK END

20. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS ECONOMY FLOWCHART BACK END

21. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS LINK FLOWCHART BACK EXAMPLE END

22. LOWEST COST FLOWCHART BACK HOW THE PROGRAM USES THE DATABASE END OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS

23. LESS THAN SPECIFIED COST FLOWCHART BACK HOW THE PROGRAM USES THE DATABASE END

24. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS BEST PERFOMANCE (DO NOT CONSIDER COST) FLOWCHART BACK HOW THE PROGRAM USES THE DATABASE END

25. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS ALL ACCEPTED DESIGNS FLOWCHART BACK HOW THE PROGRAM USES THE DATABASE END

26. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS HOW THE PROGRAM USES THE DATABASE BACK Source # 1 Source # 2 Source # … Source # 8 Source # 7 Source # 6 Source # 3 Source # 5 Source # 4 Detector # 1Fiber # 1 Fiber # 2 Fiber # ….. Fiber # 8 Fiber # 7 Fiber # 6 Fiber # 3 Fiber # 5 Fiber # 4 Detector # 2 Detector # 3 Detector # 4 Detector # 5 Detector # 6 Detector # 7 Detector # 8 Detector # … Source # XDetector # XFiber # X ACCEPTED DESIGN END

27. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS ALL ACCEPTED DESIGNS FLOWCHART BACK END

28. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS SOURCE/FIBER/DETECTOR FLOWCHART BACK END

29. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS SOURCE/DETECTOR /FIBER FLOWCHART BACK END

30. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS FIBER /SOURCE /DETECTOR FLOWCHART BACK END

31. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS FIBER/DETECTOR/ SOURCE FLOWCHART BACK END

32. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS DETECTOR /SOURCE/FIBER FLOWCHART BACK END

33. OPTICAL FIBER SYSTEM DESIGN SOFTWARE FLOWCHARTS DETECTOR /FIBER/ SOURCE FLOWCHART BACK END

34. OPTICAL FIBER SYSTEM DESIGN SOFTWARE DESIGN EXAMPLE DESIGN SPECIFICATION: LINK LENGTH=20 KM DATA RATE=140 Mbit/s BIT ERROR RATE=1E-10 SIGNAL FORMAT=NRZ SYSTEM MARGIN=6 dB BACK BANDWIDTH BUDGET : (computed) Maximum allowed risetime = 5 ns POWER BUDGET: (computed) The excess power margin >= 0 dB SOURCE DATA MANUALDESIGN RESULTMANUALDESIGN RESULT FIBER DATA DETECTOR DATA SOFTWARE DESIGN RESULTSOFTWARE DESIGN RESULT END

35. OPTICAL FIBER SYSTEM DESIGN SOFTWARE DESIGN EXAMPLE THE SOURCE DATABASE CONTAINS THE FOLLOWING TWO SOURCES: BACK END

36. OPTICAL FIBER SYSTEM DESIGN SOFTWARE DESIGN EXAMPLE THE FIBER DATABASE CONTAINS THE FOLLOWING TWO FIBERS : BACK END

37. OPTICAL FIBER SYSTEM DESIGN SOFTWARE DESIGN EXAMPLE THE DETECTOR DATABASE CONTAINS THE FOLLOWING TWO DETECTORS : BACK END

38. OPTICAL FIBER SYSTEM DESIGN SOFTWARE DESIGN EXAMPLE MANUAL DESIGN RESULT All possible combination are listed below: BACK END