FiberSim User Manual - The Information and Telecommunication
Contents
1. 44 3 4 O valucandEyePenaltyCalkculatlon 46 3 S QUIDUU ETE ear ei pad eu e need wed Aa oie alanina e t leues 47 3 0 Error MESSE Sika em xps iaa et din d d Pu Kidman Mei aa uii eus 48 Appendix A Parameter Tables for Single mode Fiber and Leaf Fiber 50 B Maintaining and Updating FiberSim Source Code uuus 51 il Chapter 1 FiberSim Overview 1 1 Background FiberSim is a Wavelength Division Multiplexing Fiber Optic Digital Transmission System Simulator Its purpose is to simulate the performance of WDM fiberoptic networks at the physical layer Fibersim is capable of modeling a wide range of modulation formats laser sources and fiber types along with a number of associated fiber and electrical system elements Fibersim allows a modeler to specify systems using aa user friendly graphical interface The interface to the application is a graphical interface that allows the user to assemble a system by clicking component icons Each components can then be individually configured through their individual dialog boxes At any point in the system whether in the electrical or optical domain the user may insert a plotting component that allows them to view the state of the system at that point in various ways The performance output views available include Eye Diagrams Pulse Intensity plots and Spectral Intensity plots At the same time Eye Penalty and Bit2. Inject ASE Noise means the noise will be considered in the numerical simulation this option 1s usually checked when the user intents to obtain small signals or to see the noise effect on system performance Post Process ASE Noise means that the ASE noise is not injected into the numerical signal but FiberSim will be aware of its affect during post processing Q value calculation 31 3 3 6 Receiver Section Receiver section is at least composed of two components de multiplexer and photodiode Optical filter and Measurement Plot can be inserted For example Optical F IF Dema lipk P koldi a Figure 28 One example of System Receiver Section 3 3 6 1 De multiplexer In FiberSim the de multiplexer includes an optical filter It filters the optical signals and shifts them to the base band Then the photodiode will detect them ini xi Demulitiplexar Optically filters an inputsigral Filter Tyne Bessel Hiter Order B 0 Half Power Point Bandwidth factor 1 5 OK Cancel Help Figure 29 De multiplexer Parameter Box Filter Type zx FiberSim offers four types of optical filters the user may click on the downward arrow to Butterworth Ideal see the list Netch left click on one of them the filter will be uploaded to the Filter Type box Default filter type 1s Bessel Filter Order B 0 Filter Order can be set by the user A very narrow higher order filter 1s not necessary
3. Copy and paste all the files to a directory on the hard drive Go to the directory where the files have been saved e Double click on Fibersim executable jar file e The FiberSim GUI window should pop up which means the installation is successful 2 1 3 Uninstalling FiberSim Uninstalling FiberSim is very simple First choose Start Window Explorer When the window explorer window is open go to the directory where the execution files are saved right click on it and choose delete from the pop up menu A message will appear and ask the user s decision again just click Yes The software will be deleted from the computer Chapter 3 Using FiberSim This chapter is meant as an introduction to the FiberSim simulation environment to a new user to learn the essentials and get started After having reading this chapter you will be able to build models on your own run simulations and see the effects of changing the various parameters 3 1 FiberSim Overview In order to setup a simulation An optical network has to be constructed first and the parameters needs to be defined using the FiberSim s Graphical User Interface which is compliant to the Windows standard and easy to use As shown in Figure 1 the menu bar and tool bar are showing at the left higher corner The left column is the navigator panel which guides the user though simulation files text outputs and different plots The blank area on the right is t
4. Frequency off of Carrier Ghz 0 0 Figure 41 User Specified Electrical Filter Parameter Box Frequency off of Carrier Ghz 0 0 The user can define the center frequency of the electrical filter according to the system requirement For example in a simulation using Vestigial Sideband VSB modulation only one side of the signal is needed If the electrical signal bandwidth is 10GHz the user may set the electrical filter center frequency at 3 5GHz with 3dB Frequency bandwidth single side of 4GHZ so one side of the signal is filtered The default value is OGHZ at baseband 3dB Frequency Ghz TS This parameter defines the 3dB bandwidth single side for electrical of the filter in GHz not the 3dB frequency factor mentioned n section 3 3 6 2 The rest parameters have been discussed in 3 3 6 2 E SPECIFICOPTFILTER E ml x Specific optical filter Optical filter with specific frequency and bandwidth filters Fitter Type Filter Order B Half Power Point Bandwidth Ghz 1 5 0 Frequency off of Carrier Ghz 0 0 Figure 42 User Specified Optical Filter Parameter Box 4 Half Power Point Bandwidth Ghz 1 5 0 This parameter defines the 3dB power bandwidth double side for optical of the filter in GHz not the 3dB power bandwidth factor mentioned in section 3 3 6 1 Similarly this feature may be also helpful for VSB modulation Default value is 15GHz e User specified De mul
5. iv Input from GUI si Use same power for all lasers Laser Powers mw 0 01 Stan Wavelength nm 1541 1 e Constant Spacing between lasers Laser Spacing 0 39 e Polarization constant for all lasers Laser Polarization Radians 4 0 Adjust frequencies for better numerical accuracy Use Ghz instead of nm Laser chirp 0 0 Figure 23 Laser Parameter Box Laser parameters can be defined through GUI or loaded from a text file To load a file check EE and fill in file name To input from GUI check Put from Gut Use same power for all lasers Laser Powers mv If every optical signal has the same power check the option and assign a value in mW Otherwise uncheck and input values separated by comma Default value is 0 01 mW Start VWiawelendgth nim The user needs to input the starting wavelength in nm the channel which has the highest frequency Default value is 1541 1 nm 24 Constant spacing between lasers Laser Spacing 0 39 For equally spaced channels just input a value in nm If the user prefers to use frequency instead of wavelength remember to check Use Ghzinsteadofnm first then input the frequency in GHz in the same box Default spacing in wavelength is 0 39 nm If the channel spacing is not constant uncheck the option and fill in values nm or GHz separated by comma ri Polarization constant for all lasers Laser Polarization Radians 4 0 This par
6. There are a few commands showing at the left upper corner of the plot Zoom Reset T j m This button allows the spectrum return to the original scale after zoom in and or zoom out To zoom out just right click the picture as long as the cursor is inside the grid area To zoom in use the mouse to draw a rectangle over the spot the user wish to see then release the mouse the enlarged portion will appear Print Plot To print the plot click on this button a printing window will pop up Then the user may pick a printer to print Of course at least a printer has to be connected to the computer File Loader w l File Loader v not important can be ignored Frequency ad Time Frequency This little menu gives the user the choices to see either the spectrum in frequency domain or the pulse plot in time domain Actually the user may just go to the Navigator Panel and click on the Spectra Plot and Pulse Plot 36 Magitude X real TY real X Power Y Power This menu allows the user to view different portions of the plot Magnitude a magnitude plot combining x polarized and y polarized signals X real a magnitude plot only shows the x polarized signal Y real a magnitude plot only shows the y polarized signal X Power a power magnitude plot only shows the x polarized signal Y Power a power magnitude plot only shows the y polarized signal For example if the
7. good for system performance because nonlinear signal distortion will become stronger in the pass band Default order is 6 32 Half Power Point Bandwidth factor 1 5 For an optical filter its double side 3dB bandwidth factor needs to be defined Default value is 1 5 which is commonly used For example if the data rate is 10Gb s full bandwidth is 20GHz then the optical filter 3dB bandwidth is 10x1 5 15GHz 3 3 6 2 Photodiode This symbol represents a standard PIN diode which detects and converts optical signals into electrical signals It also serves as an electrical filter in FiberSim E PHOTODIODE el xj Photodiode Detect and converts optical data to the electrical domain Fitter Type Filter Order JuB Frequency Factor 0 75 Quantum efficeincy 0 1 1 a Figure 30 Photodiode Parameter Box Filter Tyne similar to the DEMUX the user can pick the filter type from the same list Filter Order 6 0 The user can define the order of the electrical filter Default order is 6 346 Frequency Factor 0 75 For an electrical filter only single side 3dB bandwidth needs to be set Default value is 0 75 For example if the data rate is 1 OGHz which means the electrical signal s one side spectrum is 10GHz then the electrical filter s single side 3dB bandwidth is 10x0 75 7 5 GHz Quantum efficeincy 0 1 1 i Quantum efficiency defines how many electro hole pairs are generated per incident ph
8. 1j L LHjd L5 LR LB LRI LHld BL PI bLR L Cursor X 11 85125E 0 Y 2 870049E 5 x c RE Th ii T HTFETEHFTE TII TS ad dim gz eg gi 1 epe IE CrossHairs xn NNNM EL Time s Scaling 16 9 status done Figure 36 Pulse Plot of One Channel The example shown above is the pulse plot of a NRZ signal The plot commands and functions will not be repeated here 38 3 3 8 3 Eye Diagram L Eye Diagram the eye diagram of one channel Zoom Reset Print Plot Jitter Window Width d Draw Q Penalty Eye Diagram Plot Power vv Scaling 1E 6 Time s Scaling 1E 12 4Penaliy 0 6890B Average Power 4 816E bVV 0 62 853 BER 2 50 1E 90 Figure 37 Eye Diagram of One Channel A couple of features need to be mentioned here for eye diagram One 1s that Q value Eye Penalty BER value and Average Power of this channel are shown at the lower left corner of the eye diagram also see section 3 4 Secondly the jitter window width of the eye diagram can be enlarged or reduced by the Jitter Window Width user by inserting a number in the Which is shown on the top of the plot Default width is 0 a straight line For certain tests there 1s lots of noise in the system and FiberSim may not be able to find the best jitter window for the eye diagram Then the user may draw the jitter window using Draw G Penalty Just click on it and plot a rectangle over the eye opening area Th
9. Error rates are calculated FiberSim was produced by the Lightwave Communication Lab part of the Information amp Telecommunication Technology Center ITTC at the University of Kansas The original source code of FiberSim resides in the ITTC computer network and 1s maintained and updated through WinCVS Control Version System 1 2 FiberSim Source Code Organization The source code is organized in WinC VS as follows fs Main Directory has the configure script for the make files eco Documents on various things CVS FiberSim background etc set ibersim Old version of the C code fibersimRFF Old version of the C code ER ibersimmrrp nee Old version of the C code fibersimSCM Current working version of the C code facies Old version of the Java code e ik Old version of the Java code gui Horizon Oo Current working version of the Java GUI code manual Simple guide of how to use the GUI desme ns Contains the GIF images used in the GUI emeli Code used for the installation program Maker ites Contains commands for compiling working Contains executable files created through compiling All of the above will be created when the code 1s checked out for the first time except working directory which will be created automatically when compiling of the source code 1s done Another directory that is of importance 1s the projects Fiberspec directory This directory 1s located on devnull ittc
10. Window This window tells the user which carrier Q value is being calculated and allows the user to stop the calculation by pressing pAUR i 46 At the same time the calculated values are being displayed in the drawing area For example Carrieri D SubCarrier 1 QPenalty z 84dh 14 620 Average Power 3 717E 4W BER 1 Q02E0 Carrier 1 SubCarrier l QPenalty 2 205db 14 256 Average Power 4 651E 4W BER 1 O10 Carrier 2 Sublarrier l Penalty z 125db Q 14 323 Average Power 4 346E 4W BER 1 007E Carrieri 3 SubCarrier 1 QPenalty z 388dh 13 33 Average Power 4 672E 4l BER 1 04ED Carrier 4 SubCarrier 1 Penalty z 271dh 14 254 Average Power 4 03LE 4l BER 1 024E0 Figure 53 Q Calculation Results Each row shows the values of Qpenalty eye penalty Q Average Power and BER of one carrier The units are included 3 5 Output File In the Navigator Panel see 3 2 4 the user always sees a button under any test By clicking on it the complete output file printed by source code will show up in the drawing area FiberSim testi File Simulation alue Done reading this component Now reading in SIMPARAMETERS Done reading SimParamaters Now reading in NRZ Done reading this component Now reading in ELECFILTER Done reading this component Now reading in LASER Done reading this component Now reading in MODULATOR Now reading in MULTIPLEXOR output file Done read
11. define the simulation bandwidth in THz of each test The default simulation bandwidth is 2 times the signal bandwidth Users may also check the option Use specified bandwidth below first and input the bandwidth they wish in the box This is one of the most important parameters in terms of required CPU simulation time which should consequently be chosen with great care 3 3 2 4 Simulation Options vj Use Composite Channels In a simulation of WDM system it 1s better to check this option It treats all the channels as one composite channel so the XPM between channels becomes SPM Use low memory model This option reduces the number of samples and removes the buffers n Fiber The memory can be cut by about half but it will take longer time to simulate 21 3 3 3 Transmitter Section Now the Simulation Parameters have been set the user is ready to design the optical network starting with the Transmitter Section The user may choose to use global variables and fill in the variables names into any of the dialog box mentioned later on see section 3 2 1 2 3 3 3 1 Pulse Generators A NRZ and RZ rectangular pulse generator To view its parameter box double click on the icon zir E lolx nrz On Of Keying encoded data source may be NRZ on RE econded Number of data streams 4 0 Random number seed 301 0 Duty cycle of pulse 1 Constant data Rate Gh s Bit Rate nf data streams GHz 10 0 Do hit
12. end cdf multiplexor cdf opticalfilter cdf psk pdf specificdemux cdf specficphotodiode cdf chartl 16 gif chart2 24 gif CustomElecFilter gif delete gif EyeDiagram gif FiberDialog gif fs png IteratorEnd gif keys24 gif left gif Mux gif myControl24 gif MySave gif notel gif NRZ gif NRZDialog3 gif open2 gif OptDetect gif plot gif PlotDialog3 gif RamanFiber gif save gif savel gif SimulateDialog gif SpecificDemux gif SpecificPhotoDiode gif xbutton16 gif customoptfilter cdf fiber cdf laser cdf nrz cdf photodiode cdf ramanfiber cdf specificelecfilter cdf displaying the component icons saved in icons folder chart1 24 gif chart3 16 gif CustomOptFilter gif Demux gif EyeDiagram2 gif FilterDialog gif FSIcon gif IteratorStart gif Laser gif logo4 png MuxDialog gif myHelp16 gif new gif note24 gif NRZDialog gif open gif OptAmp gif OptFilter gif PlotDialog gif PSK gif right gif savel gif SimParamDialog gif simulateDialog2 gif SpecificElecFilter gif SpectralIntensity2 gif A e FSP Files a dealing with the Sweep function in source code 2variablesweep fsp example fsp example spacing fsp init fsp All of the files above are saved in a disc FiberSim disc which will be used for installation of FiberSim To install FiberSim please follow several simple procedures showing below Insert the FiberSim disc into the floppy drive Open the disc from the floppy drive
13. labeled User Variables for who Double Click on PATH n Add in the Variable Value Field C gec bin to the end of the text there o Click OK to finalize everything For Windows 95 98 ME c Edit C Autoexec bat d Add the line PATH PATH C gcc bin Installing WinCVS CVS is version control software It allows the group to work together without too many headaches How to Install WinCVS 1 Open the zip file P Fiberspec windows ToolVWinCvs 120 zip 2 Extract the files to C temp 3 Execute the setup exe in C temp WinCvs 120 4 Follow default setup instructions 5 Edit the environment variables For Windows NT XP 2000 Right click on the My Computer Icon on the desktop select Properties Select the Advanced Tab on the top of the window Select Environment Varibles Inside the box labeled User Variables for who Click on New 0t 0 nana 53 u Enter in the Variable Name Field CVSROOT v Enter in the Variable Value Field local p Fiberspec CVS w Click OK to finalize everything For Windows 95 98 ME e Edit C Autoexec bat f Add the line CVSROOT local p Fiberspec CVS Step 6 Using WinCVS 1 2 Checking out the source code latest version This is useful for the first time that WinCVS version 1 1 or 1 2 is run and when things get corrupted 1 Create the directory C fs
14. one global variabl If the laser power and the fiber length are changed to 50mW and 50km in next test the user only needs to go to the Variable Editor window to replace 100 by 50 Otherwise they have to click on each dialog box and do the same thing twice ww Simulate _ p displays a window The user will be asked to assign a name to the test before pressing Do Simulation The details of running simulation will be discussed in section 3 3 11 later on 11 3 2 2 Toolbar Figure 9 FiberSim s Toolbar Actually Toolbar is just a shortcut for Menubar The user may already have some ideas from the symbols Starting from the left the first one is New the second 1s Save the third means Open and the last one is Simulate Their functions have been explained in 3 2 1 1 3 2 3 Component Icons There are total 23 optical components in FiberSim Each of them is unique and has its associated parameters EZ a laser optical source please see section 3 3 3 2 EH EE pulse generators NRZ RZ and PSK please see section 3 3 3 1 ae specified and custom electrical filters user can specify the filter bandwidth or input filter data from file please see section 3 3 10 an electrical filter please see section 3 3 7 1 J an ideal modulator The output power P t is directly proportionally to the electrical signal input v t Please see section 3 3 3 3 ES ES symbols of l
15. time along a single mode fiber Stimulated Raman Scattering effect is taken into account during the simulation Compared with single mode fibers Raman fiber has two more parameters associated with pumps Pump Frequencies Ghz 300 0 Pump Power mw 1 D The user may define the pump s power mW and frequency GHz Multiple pumping 1s also allowed the user just needs to input the values separated by comma Default pump frequency is 300GHz and default pump power is ImW 30 3 3 5 Optical Amplifier gt This component simulates a standard Erbium Doped Fiber Amplifier EDFA Dialog box for this icon is shown in Figure 27 Disi Optical Apmlifier Flat gain optical P Gain dl Input Component Loss dH Output Component Loss dB ool Inject ASE Noise _ Post Process ASE Noise Hoise Figure 5 0 OK Cancel Heip Figure 27 Optical Amplifier Parameter Box GamidH 25 0 The EDFA gain is expressed in dB Default value is 25dB Input Component LossidB 0 0 Output Component Los S dBy 0 0 If non ideal amplifier 1s desired the user can decide how much loss will come from the amplifier input and output in dB The default values are OdB loss which represents an ideal amplifier characteristic Noise Figure 5 0 Noise figure 1s a unitless parameter Default value 1s 5 lvi Inject ASE Noise Post Process ASE Noise ASE noise can be either included or excluded in the simulation
16. ukans edu and must be mounted The Fiberspec directory contains numerous runs in various directories and probably need to be cleaned up a little bit once a while This chart will make sense of the important directories and their contents projects Fiberspec Backed up projects directory CVS Version control directories demo83 Sprint Runs These are important because sprint give us money isem CD Contents When creating a deliverable replace the executables and the Jar files present in these directories Seen Directories for various architectures executable igus Where the FiberSim GUI jar file is Men e Where the Install jar file 1s gt Directories for various architectures JRE so that the installer will run des redrse Compressed JRE s for various architectures e Older version control directories wdm pure Original Matlab code that this project is based on pem Probably a run or something that needs to moved More information about the class hierarchy function structure data flow diagram of the source code 1s saved in P Fiberspec docs html in ITTC network 1 3 FiberSim Component Library Optical Components Single Mode Fiber single or dual polarization nonlinear equation model including linear and nonlinear effects at choice dispersion SPM XPM FWM Raman scattering parametric gain birefringence and PMD Raman Fiber signals and pumps can co propagate in the fiber at the same time Stimulated Rama
17. 2 Open WinCVS Start gt Program gt GNU gt WinCvs 1 2 gt WinCvs 3 Go to Admin gt Preference 4 Type in the path where the CVSROOT is stored P Fiberspec CVS in the column Enter the CVSROOT then click OK 5 Go to Create gt Checkout Module 6 The directory for checking out needs to be set to c fs and click OK 7 In Enter the module name and path on the server enter fs and click OK 8 Wait while it pulls all of the files from the server Note if using a different version of WinCVS the descriptions in the popping up windows may be different but the procedures should be the same The source code includes C code taking care of simulation and Java code generating GUI e C code inside fibersimSCM folder 1 C Header Files FileName h Barrier h BesselFilter h BitRand h ButterworthFilter h ComplexMath h Component h Consts h CustomFilter h EnvelopeMatrix h extended ifstream h FFTWrap h Fiber h Filter h fsthread h getopt h IdealFilter h Laser h MachZehnderModulator h Matrix h Multiplexor h NormalRand h NotchFilter h OOKGenerator h OptAmplifier h PhotoDiode h Plot h 54 2 3 PSKGenerator h SignalGenerator h SimulationGroup h Stropts h ThreadManager h Varlist h RamanFiber h SimParameters h Simulator h Threadable h UniformRand h Vartypes h C Source Files FileName c Barrier c ButterworthFilter c C
18. 4227e2e 06 ISUNITFORHPOWER True LASERPOWERS le 05 le O5 le 5 le amp e 5 ISCOPOLARTZATION True POLARIZATIONS oO 000 SPACING ISFREQ False ISSPACINHGCONSTANT True Figure 55 A Portion of Output File The laser s power wavelength polarization etc are showing in the file e At the end simulation time will be displayed The output file includes lots of information and may become very helpful for debugging The parameters stated have meaningful names so the user should not have much difficulty to understand the output file 3 6 Error Messages A general error message is shown below 48 Program Error 1 FiberSim exe has generated errors and will be closed by Windows Y au will need ta restart the program An erar lag iz being created Figure 56 An Example of Error Message It is generated by the source code during simulation The user may start with checking the parameter values and the network design If there is a memory problem associated with the simulation a similar error message will pop up and state that the memory is not enough Sometimes the simulation 1s finished but the results cannot be viewed The user can click on L ERR in the Navigator Panel Some types of errors may be shown some may not 49 Appendix A Fiber parameters for Single Mode Fiber and Leaf NZ DSF Fiber Single Mode Fiber Leaf Fiber Fiber Loss a dB km 0 25 0 25 Dispersion D ps nm km 16 7137 3 7706
19. Dispersion Slope So ps km nm 0 09 0 1143 Effective Core Area Aert um 83 72 Nonlinear Refractive Index n 3 2 3 2 m Watt Raman Oscillation Constant 7 fs 12 2 12 2 Raman Decay Constant t fs 32 0 32 0 Raman Delay Fraction fr 0 24 0 24 50 Appendix B Maintaining and Updating FiberSim Source Code An Overview FiberSim is written by the people who work in the Lightwave Communication Lab of Information amp Telecommunication Technology Center TTC at the niversity of Kansas It resides on ITTC network under a public directory devnull projects Fiberspec The original source code of FiberSim is maintained and updated through WinCVS Control Version System a software allowing multiple people to view and modify the code together CVS can keep different versions of the source code on the network and protect them from outside users CVS can be either downloaded from devnull projects Fiberspec windows Tool WinCvs120 zip on ITTC network or from the Internet To modify the source code the user has to check out the code to a local machine from the ITTC network using CVS In this way the original code will never be touched and is kept safely in the network After modifying the code the user needs to make sure the new version of the code is truthful and correct then they can update the new version into the network again using CVS When CVS is used at the first time in the local machine a As directory will be created by CVS i
20. The user will see file lists see Figure 33 shown in the Navigator Panel e Plato e C Loop o 5 Full Spectrum Plat 4 aPenalty C Carrier 0 184 668 THz 3 spectral Plat A Eye Diagram 4 Pulse Plot Figure 33 One Example of Graphical Output List 3 3 8 1 Spectrum Plots e Full Spectrum Plot _ This plots shows the entire spectrum which includes all the channels in a WDM system For example in a 4 channel system the full spectrum plot is shown in Fig 34 Full Spectrum Plot Zoom Reset Print Plot File Loader v Frequency v Magitude nie y label Power dB Scaling 1E0 Cursor 194 2755E3 Y 16 14403E0 CrossHairs OS 0516EJ 3 40 T2BBSED Frequency Ghz Scaling 1E3 Figure 34 One Example of Full Spectrum Plot Status done 35 The plot displays its title x label and y label and the units and scaling are also shown next to the labels EM The plot also displays the cursor coordinates next to the y axis and the coordinates will keep changing according to the position of the cursor when the mouse is moving across the spectrum CrossHairs not important can be ignored status HONE Plot status is showing at the left lower corner of the plot Since some plots may take a long time to display this mark will let the user know which step the plotting process is at The usual procedures are Bit Creator File Loader type name Filter TN Inverse Fourier Transform gt done
21. The University of Kansas A 2 Information and CX Telecommunication Xe Technology Center Technical Report FiberSim User Manual Minnan Fei Chidambaram Pavanasam and Kenneth Demarest ITTC FY2004 TR 22737 01 January 2004 Project Sponsor Sprint Corporation Copyright O 2004 The University of Kansas 2335 Irving Hill Rd Lawrence KS 66045 7612 All rights reserved Contents Chapter 1 FiberSim Overview PI IM ee lt a DM RR l 1 2 FiberSimSourceCodeOrganizatlon l 1 3 FiberSim Component Library sir eanan EEEE E 3 Chapter 2 Installation Guide 2 1 FiberSim for Windows 4 2 l IlInstallattonProcedures men 4 2 1 2 Uninstalling PADers1tn ios e eon ERR E ETE lee kia irk inant 4 Chapter 3 Using FiberSim S E TDEED CO VOEVIO WS a aaa R dinen simya dada 7 3 2FiberSimGraphicalUserlnterface 9 Rl e e SR e O TR 9 52 2 TOODA keselim di oa Atene Asc prae A OA Orne di ide 12 3 2 5 C OtHDORC HE ICONS eyer alk E TR DORADO V PERRA TU 12 302 2 INBVAB TOT Ff Ane Da oes To Er dA a De qa NEA SA li ue dA 14 22 9 WAU PIE WIBdOWS ir a e istos od uadit ern Su elliye Gb edit a 15 OSEE cM belium 16 3 3 1 ConstructingFiberOpticNetwork 18 3 5 2 STER PR on PATE QUTIG TES aim le tou Mop em lm ele 20 Jo 2 JT apu e eR A 2 5 5 2 2 hadim IS d sus dec idi oho men ed E
22. Us 2 Y If the computer operating system has multiple CPUs the user may decide how many CPUs they want to simulation the test More CPUs will take shorter time to simulate However if there is only one CPU just choose 1 To upload the number of CPUs click on the downward arrow to view a list then click on the number Do Simulation Cancel will let FiberSim start Calculating and will cancel the action There is an option called Sweep click on it the window will become 44 Fi Sweep Dialog vane i O p to lw DoSimutation Do Simulation Cancel Cancel Figure 49 View of Sweep Window If the user wants to simulate a series of tests with only one different variable value this feature may become handy The following example explains how to use it Say the user needs to simulate four tests The only difference between the tests 1s the laser power will increase by 1mW every time starting with 1mW First pick a variable name for the laser power such as LaserP and insert it in the laser dialog box see 3 3 3 2 Then assign a name diff LaserP tests Fill in variable LaserP fromj jup toja lin Press Do Simulation button The simulation will repeat four times automatically with different laser power values and outputs four test files shown in the Navigatior Panel with names like diff LaserP_tests LaserP 1 0 diff LaserP_tests LaserP 2 0 diff LaserP tests LaserP 3 0 di
23. ameter defines the degree of polarization of each laser in Rad Similar to previous parameters one value is needed for constant polarization or a set of values separated by comma for non constant polarization 0 Radian means the signal is aligned with the x axis Its default value is 4 Rad 3 3 3 3 Modulator pe An ideal modulator is used to modulate electrical signals onto optical carriers It has no parameters for users to set The output power P t is proportional to the electrical signal input v t This modulator is similar to a sin modulator biased at 7 2 Its coding is implemented in Laser C FE MODULATOR EE cl xl Modulator wWodulate an slectical signal on to a optical carrier OK Cancel Help Figure 24 Modulator 3 3 3 4 Multiplexor aS A standard multiplexor combining optical signals into one composite channel It has no parameters for users to set Its coding 1s implemented in Laser C loi Multiplexar The multiplexoar combines seperate optical signal into a single link Figure 25 Multiplexor 25 3 3 4 Optical Fiber 53 This symbol represents optical fiber Double click on the icon its parameter box will appear see Figure 26 This 1s the most important and complex dialog box of FiberSim since it allows the user to introduce all the physical parameters of the fiber ESSFIBER ER Ini xl Fiber Full fidelity fiber model Fiber Length km Standard deviation of Fiber Length Wi Auto Ad
24. computation The most complicated and important component optical fiber is s mulated by using the standard Split Step Fourier method to solve the nonlinear Schrodinger equation Extremely long fiber links may be simulated on a large time window with excellent accuracy 3 2 FiberSim Graphical User Interface This section is a detailed guide for the input out interface Users familiar with PC software should have no difficulty in understanding how to work with FiberSim 3 2 1 Menubar FiberSim s menubar provides two options File and Simulation File menu 1s used to control and edit the simulation projects Simulation menu takes care the simulation issues 3 2 1 1 File Menu File menu has seven commands which can be chosen by left click on it Fei FiberSim example File Simulation Hew Window m NS 53 Save Save As Figure 5 File Menu Hew Window It lets users work on several simulation projects at the same time Every time click on it one more window will pop up then click pen to open the project wanted in each window Oe DSI Whenever creating a new project and working on a test at the first time the user may use Save as to save this test after constructing the circuit then choose a directory and assign a name to it Or it saves the current project into a new file with a new name Dos When modifying the same test just hit it to save the newest vers
25. dwidth Thz 1 4 0 Stimulated Raman Scattering has a gain spectrum falling in a range of 10 to 14 THz Users may decide how wide they want the gain spectrum to be Default value is 14 THz taui Raman oscillation constant fs 1 2 2 tau Raman decay constant Ts 32 0 Raman delay fraction 0 24 t fs v fs and fr are three constants associated with Raman effect Those values shown above are the most commonly used values for the three constants in optical system v Include Self Polarization Phase Modulation ii Include Cross Polarization Phase Modulation FiberSim also allows the user to decide whether they want to include Self Cross Polarization Phase Modulation in the simulation Switching on the first option delayed SPM 1s included Switching on the second option delayed XPM and delayed FWM are included For explanation of delayed or instantaneous terms please see section 5 3 Of course the two options can be turned on or off at the same time 3 3 4 1 4 Simulation Methods There are several simulation methods for the user to choose from depending how fast and how accurate the user wants the result to be lnoctantaninic Ann l moar Geennrerea IS TaManious Mon meal ReSponce This simulation method only includes the instantaneous nonlinear effects SPM XPM and FWM It takes the shortest time to simulate but with the least accuracy Full Delayed Non Linear Responce To include delayed SPM and or delayed XPM
26. e Q value mainly depends on the height of the window Changing the width of the window will not affect the Q value much 39 3 3 9 Multiple Spans ima ean These two icons represent loop begins and loop ends respectively which allow FiberSim to simulate multiple spans The two symbols groups a portion of the network and iterates it N times set by users The resulting structure 1s equivalent to a chain of identical components the output of one feeding the other For example a fiber followed by an amplifier 1s often iterated To set the iteration times 6 spans by default click on the loop begins icon f241TERATOR_BEGIN EN iul xi Loop beuin Loop from here to loop end number of times Humber of loops through section B OK Cancel Help Figure 38 Iterator Parameter Box A simple example of multiple spans 1s shown below Figure 39 One Example of Multiple Spans There is no parameter associated with loop ends icon ei lolx Loop end The end of the loop Figure 40 Loop End Dialog Box 3 3 10 User Specified Components e User specified electrical and optical filters E Symbol for user specified electrical optical filters The user may distinguish them from their titles shown on top of the icon 40 EE SPECIFICELECFILTER B inl xi Specific electrical filter Electrical filter with specific frequency and bandwidth filters Filter Type Filter Order 3dB Frequency Ghz 7 5
27. e on The whole process should take a while The user will see a list of compiled files showing up in the screen After compiling a working directory will be generated automatically under C fs Three executable files FiberSim exe FiberSim jar fsloader dll Channel files Image files and FSP files generated from compiling are save under the working folder Sometimes the user may need to clear all of the object files and the execution files simply type make clean and then make Step 8 Starting FiberSim After the compiling 1s done FiberSim is ready to run To run the code either double click on the FiberSim jar file in the working directory or type in the following command java jar FiberSim jar in the Command window under C fs working Either command will start the program Further information are located on the fs docs directory this documentation may not be up to date 57
28. ect see section 3 3 1 51 Detailed Procedures When maintaining and modifying the source code of FiberSim in a local computer WinCVS GCC C compiler and JDK Java compiler are needed These software compiler packages can be downloaded from the Internet Also they have been saved to the ITTC network To download and use the software compiler please read the following Step 1 Step 2 Step 3 Creating a map to the ITTC projects directory This step will create a PN drive that maps to devnull projects in the local machine How to map the drive 1 Right click on the My Computer Icon on the desktop 2 Select Map Network Drive 3 Change the Drive letter to P 4 Enter in the Folder box devnull projects 5 Make sure that the Reconnect at logon checkbox 1s checked 6 Click the Finish button Installing An Unzipping Tool If the local machine has Winzip 8 0 or above just skip this step Otherwise an unzipping tool is necessary for completing the installation The Installer is located at P Fiberspec windows Tools winzip80 exe Execute the installer and follow it s directions This should be fairly straightforward Installing Java JDK 1 3 Java is an integral part of the program and by installing it java will make running the code that much easier Also most of the debugging code 1s dumped to a command window so it is important to follow all of the steps so t
29. f FiberSim The default choice 1s to create a project Click on ok the user will see something similar to what 1s shown in Figure 13 16 Look in amp ca ies E E amp crabat3 2 7 bin 2 Dell CJ Documents and settings 7 fftw flexim gcc CJ include File name Save Files of type All Files Cancel Figure 13 Creating a Project in FiberSim The user needs to select a directory to save the project They may click on the downward arrow in Look in to choose the path Then the user has to assign a name to the project by typing it in the area after File name Finally click on Save Now the GUI looks like i FiberSim ProjectName SES File Simulation Glee Projecthiame 4 nem Figure 14 First View after Creating A Project Notice that the project name will show up in the Navigator Panel Click on the name the component icons will appear 17 kil FiberSim ProjectName ag EC lOl x EEA E3 rue ES 09 ees Figure 15 Complete GUI View after Creating A Project To open an old project a very similar window as shown in Figure 13 will appear with an Open button instead of Save button Just browse the directory to find the project then click Open After creating the project it is time to construct the network which will be discussed next 3 3 1 Constructing A Fiber Optic Netw
30. f the dispersion with respect to the wavelength the user has to define the slope value at a specific wavelength The default wavelength is 1550nm Similar to Dispersion the user has the choice to turn off 2 order dispersion 3 3 4 1 3 Nonlinearity Parameters Birefringence and PMD are two nonlinear parameters for polarization effects 7 Include Birefringence Birefringence Coeffecient ps km 0 2 If switching on the fiber birefringence the user needs to input a value in ps km If the option is turned off the parameter box will be disabled Default value 1s 0 2ps km v Include PMD birefringence overridden PMD Coefiecient ps km 5 0 2 Seed for polarization changes 1 i If turning on the PMD option the parameter box will become active The PMD coefficient 1s expressed in ps km Its default value is 0 2ps km gt Since PMD effect is a Statistical process the user also needs to set a random seed HonLinear Refraction Index m 2 watt 3 2 The nonlinear refractive index n is a measure of the fiber nonlinearity Its unit is m watt Default value is 3 2 m w for most SMF Effectrve Core Area um 2 53 0 This parameter Ag 1s used to evaluate the nonlinearity coefficient y It is expressed in um Default value is 53um for most Leaf fiber Peak Raman Factor 0 0 This parameter is used to calculate Raman gain The value filled in should be multiplied by a power of 14 by FiberSim 28 Raman Ban
31. ff LaserP tests LaserP 4 0 The user may click on any of the tests to view the results After pressing the Do Simulation button two windows will appear One 1s the simulation status window shown in Figure 50 k Status ZEE test name 1 1Bl x Stop Pause Setting up Fiber calculations new fiberLen 2 47827 m Gamma is 0 00244 7487524 Center wavelength 1 556 06 Current wavelength 1 541685e 06 Beta 2 0 Beta 3 0 Performing Fiber Calculations eee L L na errors Figure 50 Simulation Status Window 45 The other is a black window created by the source code In Windows 2000 operating system nothing shows up inside it However 1f running FiberSim in DOS environment some calculations will be displayed here Figure 51 Simulation Window II To pause the simulation just click on PaUS amp Figure 50 The same button will change to ae right away which resumes the simulation To stop the simulation click on Brom two simulation windows will disappear The output data until the stop point can be viewed by clicking on in the Navigator panel 3 4 Q value and Eye Penalty Calculation FiberSim is able to calculate and output the Q value eye penalty bit error rate BER and average power of every channel Click on button aPenatty shown in the Navigator Panel a status window will appear loj xi carier 5 subcarrier 1 Status Hit Hiecreator Stop Figure 52 Q value Calculation Status
32. hat it will be easier to use the command line tools for debugging the system How to install JDK 1 3 1 First execute the installer located at P Fiberspcec windows Tools j2sdk1_3 0 win exe 2 When the program asks for where to install the software change the path to Ck 3 When installation finishes the command line path needs to be set For Windows NT XP 2000 Right click on the My Computer Icon on the desktop Select Properties Select the Advanced Tab on the top of the window Select Environment Varibles Inside the box labeled User Variables for who Click on New Enter in the Variable Name Field PATH he AE SE 32 Step 4 Step 5 g Enter in the Variable Value Field C jdk bin h Click OK to finalize everything For Windows 95 98 ME a Edit C Autoexec bat b Add the line PATH PATH C jdk bin Installing GCC GCC 1s a free compiler It is used because it 1s also installed on the Linux and Alpha boxes and just about any other machine in ITTC How to install GCC 1 Open the zip file P Fiberspec windows Tools gcc zip 2 Extract the files to C gcc 3 Edit the environment variables For Windows NI XP 2000 1 Right click on the My Computer Icon on the desktop J Select Properties k Select the Advanced Tab on the top of the window l Select Environment Variables m Inside the box
33. he place to build circuits Users can pick from the drawing palette the component they wish to use which 1s represented by a standard yellow symbol often used by other fiber optic softwares The component icon will be displayed automatically in the blank area following a left click By double clicking on each component the user can define the values of its parameters Once the optical system 1s designed a typical window looks like gi FiberSim example example test 2 Stesti newWDM Fer Optical Figure 1 General View of FiberSim Environment As soon as the numerical simulation is done the results are available and they can be viewed by selecting the corresponding command in the navigator panel The graphical results such as eye diagrams spectra etc will be plotted and displayed by FiberSim while all numerical results such as Q calculation and eye penalty are displayed as text Figure 4 Spectral Plot FiberSim has the capability of simulating long haul WDM system with all types of nonlinear effects such as dispersion SPM XPM PMD etc All simulation components are based on a time domain
34. ing this component Now reading in ITERATOR BEGIN Done reading this component iii sweep test 1 0 Now reading in FIBER 4 sweep test A 2 0 Done ioa UCM component 7 sweep test A 30 Now reading in OPTAMPLIFIER Gl sweep_teskA 4 0 0 reading in PLOT D test3 Done reading this component 3 newwom Now reading in ITERATOR END Now reading in DEMUX Done reading this component Now reading in PHOTODIODE Done reading this component Checking Component On Off Key Signal Generator Checking Component Filter Checking Component Laser H Checking Component Multiplexor Checking Component Iterator Figure 54 Output File Window Usually the output file is very long The user can move the scroll bar or click on the up down arrow to view the whole file e At the beginning of the file the user may see something saying reading and checking the component XXX 47 e Then it is the simulation section including parameters such as simulation bandwidth wavelength data rate etc e Following statements tell the user that each component is being executed and related parameters are also displayed The user will see sentences like Now Executing Component Name For example Wow Executing Laser ISINPUTFILE False LASERFILENAME laser txt ISINFPUTGUI True ADJUSTFREQUENCIES False CHIRP WAVELENGTHS 1 54112e 06 1 541496 06 1 54166e 06 1 5
35. ion a Bente It allows the user to build a different project Close Exit Close closes the present window usres are working on Exit means quitting the whole program all of the FiberSim s windows will be closed 3 2 1 2 Simulation Menu Simulation menu has three functions as shown in Figure 6 n Simulate Advanced Simulate BD Bea pig Figure 6 Simulation Menu Edit Variables _ Tt defines global variables for dialog boxes used in FiberSim Click on it a window will pop up E variable Editor ml x eee ean Figure 7 Edit Variable Window 10 If the user decides to define some global variable they will need to input the global variable s name and value into the corresponding column Wherever the global variable s value is needed just fill its name into the parameter box In this way the user only need to edit the global variable in the Variable Editor window instead of typing in the number in every place using the same value For example if the laser power and the fiber length are 100mW and 100km respectively A global variable can be defined as E25 variable Editor E ml xj One global variable C www eme Figure 8 One Example of Defining A Global Variable Then in the corresponding laser and fiber parameter boxes the user should input the global variable s name instead of 100 Laser Powers mw One global variabl Fiber Length km
36. irements This section defines the system minimum requirements to install FiberSim Please check that your system matches all the requirements before installing FiberSim Hardware Requirements Pentium II 128 Mbytes RAM At least 5 Gbytes of free disk space CD ROM drive Graphic display with a resolution of 1024x768 pixels or higher color is optional but highly recommended e Keyboard and two or three button mouse Software Requirements e Microsoft Windows NT XP 2000 98 95 Server e TCP IP communication protocol 2 1 2 Installation Procedures To run FiberSim successfully the following files have to be included e Executable Files generating the GUI and call the source code to perform simulation m 2 FiberSim jar E FiberSim exe md fsloader dll e Channel Files 4 taking care of the GUI dialog boxes customdemux cdf demux cdf iterator begin cdf modulator cdf optamplifier cdf plot cdf simparameters cdf specificopticalfilter cdf Image Files BER gif Char2 gif CustomDemux gif DCG gif ElecFilter gif Fiber gif fs gif full screen gif keys16 gif LaserDialog gif Modulator gif myControl16 gif myHelp24 gif new 16 gif note24 trans gif NRZDoialog2 gif openl6 gif OptAmpDialog gif PhotoDiode gif PlotDialog2 gif PulseIntensity gif runCombo gif savel 2 gif simulatel6 gif SimulateDialog3 gif SpecificFilterDialog gif TxFilter gif customelecfilter cdf elecfilter cdf iterator
37. just Step Size Number of Steps hei Include Loss Loss Dh km Include Dispersion Dispersion Factor psinm ikm i Include Second Order Dispersion Dispersion Slope Factor ps nm 2 km 0 11 42 Dispersion Slope amp Wavelength nm 1 550 0 J include Birefringence Birefringence Caetieciem sikim si Include PMD birefringence overridden PMD Coeffecient ipsikm 4 0 2 Seed for polarization changes 1 D je Include Self Polarization Phase Modulation Instantanious Non Linear Responce Full Delayed Non Linear Responce C3 1st Order Moment Approximation Co 2nd Order Moment Approximation Average Riemann Method Skip Factor C3 Direct Integration im FFT Method HonLinear Refraction Index m 2 watt Effectme Core Area um 2 Peak Raman Factor Raman Bandwidth THz taui Raman oscillation constant fs tay Raman decay constant fs Raman delay fraction Figure 26 Optical Fiber Parameter Box 26 3 3 4 1 Single Mode Fiber FiberSim 1s capable of simulating different types of fibers such as Single mode Fiber and Leaf Fiber non zero dispersion shifted fiber depending on the dispersion coefficients the user input from GUI 3 3 4 1 1 Basic Parameters Fiber Length km 1 00 0 The estimated length of fiber is defined n km Default value is 100km Standard deviation of Fiber Length 0 0 This parameter is defined in km also If the actual length of the fiber 1s not know
38. lter Optical filter defined by a file Name of file that contains the filter points ilter dat Frequency offset OK cancel Help Figure 46 Custom Optical Filter Parameter Box Name of file that contains the filter points ilter dat Users may load filter data from a file so they will have the exactly filter they wish for Frequency offset i The electrical optical filter center frequency needs to be set in GHz Default value is 0GHZ e Custom De multiplexer Ea CUSTOMDEMUX Custom Demultiplexor Demultiplexor filter defined by a file OK Cance He Figure 47 Custom Demultiplexer Parameter Box Since the demux works as an optical filter the user can load the filter data from a file too and set the center frequency 43 3 3 11 Running and Stopping Simulation When a network has been built and the parameters have been defined it is the time for the user to start the simulation Click on 7 from the tool bar the simulation window will pop up E il Sweep Dialog xi RunName ov Numher of CPUs 2 A Sweep gt gt Do Simulation Cancel Figure 48 View of Simulation Window gt m First the user needs to assign a name to the simulation Space is allowed in the name Click on the downward arrow a menu of the old simulation tests will appear The user may choose a used name then the new simulation will replace the old one Remember the old test will be lost Number of CP
39. n Scattering effect is taken into account during the simulation Linear and nonlinear effects are same as common fiber Source Laser single or multiple channel Modulator Ideal output power is directly proportional to input voltage Filters Bessel Butterworth Ideal Notch and User defined Amplifier EDFA model Photodiode PIN Multiplexer Demultiplexer Electrical Components Data Sources NRZ RZ and PSK Filters Bessel Butterworth Ideal Notch and User defined Measurement Tool Measurement Plot includes pulse plot electrical domain spectrum plot optical domain and eye diagram electrical domain also serves as Q value BER Eye penalty estimator User defined Components User specified Components electrical optical filters demultiplexer and photodiode Custom Components electrical optical filters and demultiplexer Chapter 2 Installation Guide FiberSim is a software written by people working in the Lightwave Communication Lab of Information amp Telecommunication Technology Center ITTC at the University of Kansas The original source code of FiberSim is maintained and updated through WinCVS control version system a software allowing multiple people to view and modify the code together The user may download CVS from the Internet Appendix B includes the information of installing amp using CVS and compiling amp modifying the source code in great details 2 1 FiberSim for Windows 2 1 1 System Requ
40. n this computer Note the directory name has to be called fs The source code C amp Java and Make files will be checked out into fs directory The C code taking care of simulation is located in fs fibersimSCM folder and the Java code taking care of the GUI is saved in fs gui Horizon folder There is another folder called jni Java Native Interface which serves as a bridge between the C code and Java code Folder fibersim fibersimRFF fibersimRFF nff gui and gui nff hold old versions of the source code They are no longer used The Make files under fs take care of compiling the source code There are three of them Makefile win Makefile linux and Makefile alpha which are used for Windows system Linux system and Alpha system respectively After successfully checking out the code onto the local machine the user needs to compile it in a Command window using the Make files Compiling creates a working folder under fs directory which contains executable files Image files and Channel files The Make files allow the C amp Java code to be compiled to form executable files create Channel files and Image files and put all the files together in the fs working directory As soon as the compiling is done FiberSim can be run in either Window environment or by typing in commands in the Command window When the FiberSim GUI pops up it is time for the user to create or open a proj
41. n with good accuracy a statistical variation can be taken into account The actual length is evaluated as Input Length Std Length Random Number Default value is 0 wi Auto Adjust Step Size Step size 1s a parameter associated with the simulation method Split Step see section 5 2 The smaller the step size 1s the longer the time takes to simulate The user can decide how small they want the step size to be by filling in the number of steps Then the step size is equal to Actual Fiber Length Number of Steps Or the user just need to choose the Auto Adjust option and let FiberSim set the step size Default value of steps 1s 200 Include Loss Loss Db ikm 1 i This is the fiber attenuation parameter If fiber attenuation is desired input the value in dB km Default value is 1 dB km 3 3 4 1 2 Dispersion Parameters wi Include Dispersion Dispersion Factor ps inmkm 3 7706 This dispersion factor D ps nm km represents the dispersion value of the fiber Its default value is 3 7706ps nm km Also fiber dispersion can be excluded in simulation by turning off the option Pn Include Second Order Dispersion Dispersion Slope Factor ps inm 2 km 0 11 42 Dispersion Slope g Wavelength nm 1 550 0 Dispersion slope dD dA is a parameter related to the second order fiber dispersion and is expressed in ps km nnY Default value is 0 1142ps km nm Since dispersion slope is a derivative which means variation o
42. names into the dialog box see section 3 2 1 2 inis Simualilon Parameters Simulator Parameters vj Use Composite Channels Humber of input bits 1 28 Humber of padding bits 1 Use low memory model Use specified bandwidth below Figure 20 Simulation Parameters Window 20 3 3 2 1 Input Bits Number of input bits 1 28 This parameter decides how long the input signal pattern will be at the reference data rate see Pulse Generator in 3 3 3 1 Of course longer pattern will give more accurate results But keeping in mind that the CPU simulation time will increases with the total number of input bits For example in soliton systems a very short pulse may be sufficient for studying propagation effects On the other hand if the user wishes to study the effects of noise of an optical system a statistic process a long pattern 1s required Default value 1s 128 3 3 2 2 Padding Bits Humber of padding bits 1 Padding bits means the additional 0 s added at the beginning and the end of the input signal pattern which makes sure that there is no overlap between two patterns For example if the user wants the number of input bits to be 32 and the number of padding bits to be 2 then the actual number of data bits is 24 3242 36 There are two 0 s at each end of the real 32 bit long signal Default value is 1 3 3 2 3 Simulation Bandwidth Use specified bandwidth below FiberSim allows the user
43. nd ERR TE NAT RERUM a 21 3 3 23S mulattonBandwidth 21 Io ADMO PHONG di lid adim 21 2 2 5 Lransipttiet DeCHODs kk deal damla lal ala lie 22 34 015 1 Pulse GENE O ose iode e DUE lde ile al 22 gt SA OSEE eee eek ense lamelli Sildi 24 334314 MOGUIATON aydan han ad addan px RR IRI 25 Dou Multiple XOT nen ode ni a me E S Ores 25 25 50 Opica TIDE amkemana sekildeki oadama 26 3 5 4 1 SingleMode FIDES ais sa la ilk edil lik ays 27 3S O4 TT Basic Parameters rassal ramis 27 3 3 412DispersionParameters 2 3 3 4 1 3 NonlinearityParameters 28 3 3 4 1 4SimulattonMethods 29 9 00 Raman ei lee Me PPM e e ee 30 2 5 9 Opica Ap Lema b medine beda buki 31 FORCIE SEC OD LE A EE au ei ant eye 32 5 5 041 De mup ESE sekmesi namal ms a asd 27 3 30 2 PhotodiOd6G reel ot A re REUS RACE anaes 33 3 3 7 Filters QN 34 55 7 1 BIeettical PAIGE uoce tee tin a P EHE RARI uS 34 35 5472 Optical PIE iecore ieas e betu OA Eun e Eni ARE UA a 34 2 3 5 MeCasuterent P OU rna ui re REO UE UN pa dI aan Up ili i 35 D205 PPCCWal PIOS aramama NTa aN 35 SES Oris WEISS LOL EN SR EM NR ER NM 38 3 940 9 yg Diara Mai ll br at ll 39 3 2 9 MAUI PIE Satis RK EMA DM MN VK bet 40 55 10 Ser Specitied Op OLS yaya damn rS ele ei 40 3 3 11 RunningandStoppingSi mulatlon
44. nd input the values separated by commas e g 10 20 30 Default value is 10 Gb s Da hits get saved to file This option gives the user an opportunity to save the data bits to a file in case the same bits needs to be used later on Do hits get loaded from file E Hame of file to save bits bits bd gt Data bits can also be loaded from a text file instead of being produced by FiberSim Just check the option and write the file name in the box The symbol ES is a shortcut for Browsing File in the Directories A window will pop up letting users to browse E3 A Phase Shift Keying signal pulse generator Its parameter box is shown in Figure 22 iix Psk Phase Shift keying encoded data source Number of data streams Random number seed M ary psk vj Constant data Rate Gb s Bit Rate af data streams Ghz 1 0 0 _ Do bits get saved to file Do bits get loaded from file Name of file to save bits pits ba n OK Cancel Help Figure 22 PSK Pulse Generator Parameter Box 29 There is only one parameter difference between PSK generator and NRZ RZ generator Duty Cycle is replaced by M ary psk This parameter tells how many different phases each transmitted bit has Default value 1s 8 3 3 3 2 Laser EZ This icon simulates a laser which 1s the optical source in optical network Its parameter box looks like Ease TE laser laser bank input from File
45. nd measurement plots can be added before after and in between fibers There is no rectangle outside the receiver section which usually consists of de multiplexer and photodiode Filters and measurement plots can be inserted anywhere in the system A simple complete optical system 1s shown in Fig 18 4 chai E Figure 18 A Simple Example of Optical System in FiberSim Deleting an item can be accomplished by the follow left click on the icon the user will see the name on top of the icon is highlighted right click the mouse a small menu will pop up 19 Figure 19 Mouse Pop up Menu then choose cut or clear they do the same job the icon will disappear Or the user may press the button Delete from the keyboard to delete the component To copy and paste just follows the same steps except choosing command copy instead of cut Then move the mouse to another place or another window right click and select paste If working on more than one items first highlight the icons by drawing a rectangle over them then copy and paste 3 3 2 Simulation Parameters Before assigning parameter values to different components the Simulation Parameters need to be defined first i e those parameters are essential to control the accuracy and duration of the simulation Its window can be opened by double click the blank area not the icons The user may choose to use global variables and input the variables
46. ng if possible 2 History Retrieval If all of a sudden the code starts going crazy the user can use CVS to back track changes and find out when the change that 1s causing problem was committed And even back up to that point and start from there Compiling the source code After checking out or updating the code from the network compiling has to be done on the local machine which creates the executable from the files There are three Make files in the Ms directory Makefile win Makefile linux and 56 Makefile alpha These Make files will take care of compiling the code in different operating systems since the compiling commands are included in the files There is also one file called Makefile inside fs directory which 1s created from previous compiling process Please delete it before compiling How to compile the code in Windows NT XP 2000 1 Open a Command Window a Click Start b Select Run c Type in command d Click OK 2 Change directory Type cd C fs 3 Copy Makefile Type copy Makefile win Makefile 4 Compile the code Type make 5 The make command will create a working directory under fs Also an icons folder holding the Image files will be created under working directory see section 2 1 2 The user will see the compiler popping up a question during compiling Icons is a filename F or a directory D Just type D or d The process will continu
47. oop stars and loop ends please see section 3 3 9 SS a multiplexer please see section 3 3 3 4 a de multiplexer please see section 3 3 6 1 12 Be specified and custom de multiplexers user can specify the bandwidth or input data from file please see section 3 3 10 a PIN photodiode please see section 3 3 6 2 EJ a specified photodiode please see section 3 3 10 3 fiber optical fiber please see section 3 3 4 w Raman fiber pumps are include in the fiber to simulate Raman effect please see section 3 3 4 5 E3 an optical amplifier please see section 3 3 5 symbol of output plots including eye diagram pulse plot and spectra plot please section 3 3 8 Le an optical filter please see section 3 3 7 2 B specified and custom optical filters user can specify the filter bandwidth or input filter data from file please section 3 3 10 13 3 2 4 Navigator Panel example test 7 7 Plot 0 7 Plot 1 3 newwWDM 5 ERR 3 QUT test 1 C Plota CJ Loop 0 5 Full Spectrum Plat 4 aPenalty D Carrier 0 194 688 THz 5 spectral Plot 3 Eye Diagram 4 Pulse Plot Carrier 1 184 617 THz 7 Carrier 2 194 568 THz Carrier 3 184 518 THz amp 7 Loop 1 Plat 1 3 newwWDM 4 ERR 5 OUT 5 new DM Figure 10 Navigator Panel Navigator panel guides the user through simulated tests and ou
48. ork Theoretically to place a component in the drawing area just pick one from the palette and left click on it then the component icon will appear in the draw area automatically connecting to the previous one If the user likes to put the component in a specific place e g between two icons or move it to somewhere else he or she needs to follow select it with the left mouse button drag it to the spot you want then release the mouse However to build a correct optical network the user has to follow certain order transmitter section is always the first following is the transmission fiber section last is the receiver section The first step is the transmitter section which 1s at least composed of three components data source a laser bank and a modulator However an electrical filter is usually added after the data source to improve the system performance There are strict rules for building this section the data source always goes first then the filter optional then the laser and the finally the modulator Figure 16 A Start of the Transmitter Section 18 As shown in Figure 17 the complete transmitter section is always bounded by a rectangle which may remind the user about the section 1 chan nek Figure 17 View of System Transmitter Section A multiplexer is always placed after the transmitter section which starts the transmission section The optical fiber usually follows the Mux Optical amplifiers a
49. oton in the photodiode The user can input any value between 0 and 1 In ideal case the quantum efficiency is 1 which 1s the default value 33 3 3 7 Filters Although the Demux serves as an optical filter and the photodiode serves as an electrical filter FiberSim has its own electrical and optical filters 3 3 7 1 Electrical Filter EEC Kal An electrical filter Actually the symbols for electrical and optical filters are the same but after the user places the component into the drawing area the component s name will appear on top of the icon which will help the user to distinguish the two icons fey ELECFILTER aloj x Electrical Filter Electrical Filter Filter Type Filter Order 3dB Frequency Factor 078 OK Cancel Heip Figure 31 Electrical Filter Parameter Box All of the parameters for electrical filters have been well explained in Photodiode section please read 3 3 6 2 for details 3 3 7 2 Optical Filter E FII An optical filter f OPTFILTER EE ic x Optical Filter Optically filters an input signal Filter Type Filter Order Half Power Point Bandwidth Factor 1 5 OK Cancel Help Figure 32 Optical Filter Parameter Box All of the parameters for optical filters have been well explained in De multiplexer section please read 3 3 6 1 for details 34 3 3 8 Measurement Plots ba This symbol tells FiberSim to output the measurement plots and Q values
50. r some information like how many carriers are in the system which carrier they are looking at and the carrier frequency By clicking on each carrier its graphical output list can be viewed The list includes Spectral Plot Eye Diagram and Pulse Plot The corresponding plot will be displayed when the user click on its name Sometimes the plot may take a while to show up depending on how complex the optical system is 3 2 5 Multiple Windows FiberSim supports multiple windows features Every time the user opens a new project or loads a previous on a new window appears This feature is very useful when one needs to cut and paste part of a project from a window to another File Simulation OEBE i a eS T OSS TT EO T Ee gg Y ee d HilFiberSim test CECR F Prete DeTe Detects Tete Dera ele Tete Dee Dna Dela eda Dee Dee alate Dele Dele lela lele lets Delelelelelelete lets Dele lelalele lets lelelelelelelebeletel t a A A rn Figure 11 View of Multiple Windows 15 3 3 Getting Started This section will teaches the user step by step to design and set up a new simulation explains how to use each component and define their parameters To start FiberSim click on FiberSim jar file a window and the FiberSim GUI will appear Figure 12 and ask the user to create a new project or open an old one EF colors 73 sports epo Figure 12 Starting Window o
51. s 1 Right click on the fs directory in WinCVS should be on the left side of the window 2 Select Update Selection CVS will take a little while to check everything and update files In the bottom right corner will be an area with a listing of everything that occurred It will show files updated with a U files that have been modified with M and files that have a conflict modified by more than one person with a C Conflicts will need to be resolved by editing the code files and removing any conflicts Also note that the files themselves that have been modified added by the user and are not committed yet will be displayed in red Viewing Changes Just simply right click on the file and select Diff Selection This will display a list of changes made to the file in the bottom right area Committing Changes Simply right click on the red file in question and select Commit Selection This will place the change to the file in the CVS archive and allow for everyone to receive the updating code which is a lot easier than emailing changes all of time Other Uses for CVS not explained in detail 1 Branching If a major change is needed it is sometimes best to branch out and create separate codes for both branches and later merge changes this allows progress to occur without loosing changes by anyone and without breaking the program altogether Merging is a tedious process so please try to avoid branchi
52. s yet saved to file Do bits get loaded from file Name of file to save bits pits ea Figure 21 NRZ and RZ Pulse Generator Parameter Box Humbher of data streams It means the total number of channels being simulated in a test Default value 1s 4 Random number seed In order to guarantee the randomness of the signal pattern generated Random number seed has to be set Pulse generators utilize those seeds to produce different sets of signal values in each run The signal randomness is proportional to the number of seed If a CW signal is required input 0 here Default value is 301 Duty cycle of pulse For NRZ signal duty cycle is always 1 When a 1 or 0 is transmitted the signal is at the High On Level or Low Off Level during the entire bit time For RZ signal the value of duty cycle can be any number between O and 1 When a 1 is transmitted the signal 1s at the High On Level for as long as Duty Cycle x Bit Duration 22 then it goes down to the Low Off Level for the remaining time When a 0 is transmitted the signal is at the Low Off Level for the entire bit time iri Constant data Rate Gb s Bit Rate of data streams GHz This parameter is used to set a reference data rate n Gb s for the simulation If the user wants a constant data rate for all the channels just check the option and fill in the data rate value If non constant data rates are desired do not check the option a
53. signal launched is only x polarized the user should see nothing from the Y real and Y Power plots also the Magnitude plot and X real plot should be the same o Spectral Plot _ This plot only displays the spectra of one channel OOTTE ee eh ee he ee ee eh ee ee ee eb ee ee ee eee Lee Dan pn i pn e EE e A E ee RS Power dB Scaling 1E0 GOVERNO E m anon vais OO A KE TF SR RL SRR mia ulace ea cai eS TA a Cursor 104 6201E3 1T 1 8 75953E0 humum ara aa a a a a a a a a a qa a a a a a a a a a a a n a a n n a a a na a a a eus a a aa a a a a ny a a ra n n E CrossHairs ES L rr p d 2 4 4 41 24 2 2 2 4R DINTEMUM MENU idEE 0 7 7 2 la e ea m ma mm ma Frequency Ghz Scaling 1E3 status done Figure 35 Spectra Plot of one channel 37 The plot commands and functions work the same way as in Full Spectrum Plot Those small peaks on the side of the spectra are caused by nonlinear distortion 3 3 8 2 Pulse Plot Li Pulse Plot the pulse plot of one channel Zoom Reset Print Plot Inverse Fourier Transform T Time ww Magitude Pulse Plot Power WV Scaling 1E 3 eee eee eee den j 1l HF4 4d bHRi HRli bRl R l d
54. tiplexer 4 User specified Demux kz SPECIFICDEMUX Specific Demultiplexor D emultiplexaor with specific frequency and bandwidth filters Bessel Filter Tyne Filter Order Half Power Point Bandwidth Ghz 1 5 0 Frequency off of Carrier Ghz 0 0 Figure 43 User Specified Demultiplexer Parameter Box Since the Demux in FiberSim serves as an optical filter the dialog box of User specified Demux is the same as the one of User specified optical filter e User specified photodiode Ea User specified Photodiode E23 SPECIFICPHOTODIODE Specific Photodiode Fhotodiade with specific frequency and bandwidth filters Bessel mi xi Filter Type Filter Order S06 Frequency Ghz Quantum efficiency 0 1 1 al lon Cancel Heip Figure 44 User Specified Photodiode Parameter Box A regular photodiode in FiberSim detects the signal and serves as an electrical filter Comparing with the normal one a user specified photodiode allows the user to specify the center frequency of the electrical filter The rest parameters are identical 42 e Custom electrical and optical filters A Symbol for custom electrical and optical filters CE o Custom Electrical Filter Electrical filter defined bw a tile Name of file that contains the filter points iter dat Frequency offset 0 0 Figure 45 Custom Electrical Filter Parameter Box k CUSTOMOPTFILTER E iul xi Custom Optical Fi
55. tput files Refer to the example shown in Figure 10 example is the project name The user only can open one project in each FiberSim window test 1 and test 2 are two different tests under the same project Every time the user starts a simulation they need to give a name to the test Once simulation is done the test name will show up in the panel Click on any of the test its output file list will pop up see the list under test 1 If there are N output plots and Plot N 1 in the list L newwDM lisan text file containing all the parameters defined in the test ERR means error messages If there is any error occurring during the simulation it will be displayed here in the designed network the user will see Plot0 Plotl 14 is the output test file providing all the information associated with simulation such as simulation time the number of sample points generated data pattern fiber step size etc The information may become very helpful when the user needs to figure out what is wrong with the simulation results Under the Plot N there are sub lists Loop0 Loop until Loop M 1 if there are total M loops in the test Click on 3 Ful Spectrum Plot it gives the complete spectrum showing all the carriers of the present LoopM Similarly calculates and outputs the Q values and eye penalties of every channel of the present LoopM 7 Carrier 1 194 617 THz provides the use
56. ustomFilter c extended ifstream c Fiber c fsthread c Laser c Main c NotchFilter c OptAmplifier c Plot c RamanFiber c SimParameters c Simulator c ThreadManager c BesselFilter c Component c EnvelopeMatrix c FFT Wrap c Filter c IdealFilter c MachZehnderModulator c Multiplexor c OOKGenerator c PhotoDiode c PSKGenerator c SignalGenerator c SimulationGroup c Stropts c UniformRand c C Object Files FileName o Barrier o ButterworthFilter o CustomFilter o extended ifstream o Fiber o fsthread o Laser o Main o NotchFilter o OptAmplifier o Plot o RamanFiber o SimParameters o Simulator o ThreadManager o BesselFilter o Component o EnvelopeMatrix o FFT Wrap o Filter o IdealFilter o MachZehnderModulator o Multiplexor o OOKGenerator o PhotoDiode o PSKGenerator o SignalGenerator o SimulationGroup o Stropts o UniformRand o 55 Step 7 e Jave code inside gui Horizon folder Since there are over 300 files in gui Horizon folder Java Source Files and Java Class Files a list of the file names will not be included here Updating code After editing the code files in whatever text editor the user chooses Xemacs Notepad Word etc The file will show up in a red color this indicates changes If there is a C next to the file it means that there is a conflict in the code which must be resolved before committing the code to CVS The following are the steps involved in updating and comparing file
57. which depends on users choices a full delayed nonlinear method must be used 29 There are four different methods that are capable of doing full delayed response e Direct Method This is the simplest method used in the time domain to evaluate the integrals of delayed response f t s hr s hr t is a fast varying function in time domain so in order to achieve high numerical accuracy a huge sampling bandwidth has to be used Therefore the method is time consuming and the numerical efficiency is poor e 1 order and 2 order Moment Methods To reduce the computation time Moment methods can be employed In Moment methods the integral is expressed as different orders of time derivatives at each sample point The more higher order derivatives are included the more accurate the simulation is e Fast Fourier Transform FFT Method Since convolution in time domain can be performed as multiplication in frequency domain so what FFT method does is to multiply the spectrum of f t and hr t in frequency domain In this way the simulation bandwidth is determined by signal bandwidth instead of the bandwidth of hr t FFT method achieves the best numerical efficiency and takes less time to simulate e Average Riemann Method This method is no longer used by FiberSim 3 3 4 2 Raman Fiber FiberSim components family has a special member called Raman Fiber in which the signals and pumps can co propagate in the same direction at the same
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