Coherent Lightwave Signal Analyzer
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1. 7 495 6647564 South Africa 41 52 675 3777 Spain 00800 2255 4835 Sweden 00800 2255 4835 Switzerland 00800 2255 4835 Taiwan 886 2 2722 9622 United Kingdom amp Ireland 00800 2255 4835 USA 1 800 833 9200 European toll free number If not accessible call 41 52 675 3777 Updated 10 April 2013 For Further Information Tektronix maintains a comprehensive constantly expanding collection of application notes technical briefs and other resources to help engineers working on the cutting edge of technology Please visit www tektronix com Copyright Tektronix Inc All rights reserved Tektronix products are covered by U S and foreign patents issued and pending Information in this publication supersedes that in all previously published material Specification and SA price change privileges reserved TEKTRONIX and TEK are registered trademarks of Tektronix Inc All other trade names referenced are the service marks trademarks or registered trademarks of their respective companies Sy 24 Feb 2014 52W 27474 6 www tektronix com Tektronix S2. AnalysisParameters Matlab XvtT vt Errored symbol in Measurement vs Time plot Datasheet 3D visualization tools Complex modulation signals are inherently 3D since in phase and quadrature components are being changed vs time The 3D Eye Diagram provides a helpful combination of the Constellation and Eye diagrams into a single 3D diagram This helps to visualize how the complex quantity is changing through the bit period The diagram can be rotated and scaled Also available in 3D is the Poincar Sphere The 3D view is helpful when viewing the polarization state of every symbol The symbols tend to form clusters on the Poincare Sphere which can be revealing to expert users The non normalized Stokes Vectors can also be plotted in this view Analysis Controls The Analysis Controls window allows you to set parameters relevant to the system and its measurements Analysis Parameters Matlab db o Meb Engine Command Fat Re Values 5eg1 A Fat Re SyncFrameEnd 100 PattXlm Values Seq Fatim SyncFrameEnd 100 Patt Re Values 5eq3 Patt Re SyncFrameEnd 100 Patt Y lm Values Seq Patt lm SyneFrameEnd 100 W Core Processing MATLAB window SignalSpectrumX LaserPhaseSpectrum amp 4 gt Vert 1 000E 001 dB Div Horiz 5 000E 000 GHz Div 10 dB Div 0 00 Ref Level dBm Signal Specii window www tektronix com 7 OM4006D OM4106D Ana
3. pee Yconst Bias Real 0 07 0 05 0 09 0 06 0 01 Yconst Bias Imag 0 03 0 02 0 01 0 04 0 01 p YconstPhaseAngle 90 19 90 19 90 18 90 17 90 17 deg Yconst Magnitude 22 079 22 072 22 097 22 099 22 091 ymw j Yconst EVM Average 15 01 14 09 14 33 14 95 16 16 Ze Yconst Mask Violat 0 5 T 12 3 Yconst Symbols Dis 2992 2992 2992 2992 2992 i Yconst Symbol Std 0 074 0 072 0 069 0 070 0 069 vmw X Trans Y Trans Pow Trans XY Measurements PMD Clear Statistics Multi carrier measurements www tektronix com 9 OM4006D OM4106D User definable superchannels For manufacturers getting a jump on superchannels or researchers investigating alternatives user definable superchannel configurations are a must Option MCS allows the user to set up as many carriers within the superchannel definition as necessary Each carrier can have an arbitrary center frequency no carrier grid spacing is imposed The carrier center frequencies can be set as absolute values in THz or as relative values in GHz Typically the OUI will retune the OM4106D local oscillator for each carrier However in cases where multiple carriers may fit within the oscilloscope bandwidth multiple carriers can be demodulated in software from a common local oscillator frequency The user is given the flexibility to specify the preferred local oscillator frequency for each carrier Multi carrierspectrumX z Center Freq 192 5 THz
4. width X X Constellation Phase Angle Measure of transmitter IQ phase angle X X Constellation and Q Bias Measure of average symbol position relative to the origin X X Constellation Mask User settable allowed EVM level Symbols violating the mask are X X counted Eye Decision Threshold Q factor The actual Q achieved will depend on the quality of the data signal the X X signal amplitude and the oscilloscope used for digitalization Using the Tektronix DPO73304D oscilloscope 4 Ch a Q factor of 20 dB is achievable at 40 GBaud Decision Threshold Q plot Displays BER vs decision threshold for each eye opening The Q value X X at optimum decision threshold is the Q factor Phase Diagram Signal Spectrum and Laser Display of signal electric field vs time in the complex plane FFT of power X X Spectrum signal or laser phase noise MATLAB Window Commands may be entered that execute each time signals are acquired X X and processed Measurements vs Time Optical field symbol center values errors and averaged waveforms are X X displayed vs time in the OUI any parameter can be plotted vs time using the appropriate MATLAB expression 3D Measurements 3D Eye complex field values vs time and 3D Poincar Sphere for X X symbol and tributary polarization display Differential Eye Diagram Display Balanced or single ended balanced detection is emulated and displayed X in the Differential Eye Diagram Frequency Offset Frequency offset between signal and refe
5. 3 Years including warranty Opt R5 Repair Service 5 Years including warranty Software options QAM Adds QAM and other software demodulators MCS Adds multi carrier superchannel support OM2210 Coherent Receiver calibration source configuration recommendations When used with OM4006D or OM4106D Receiver Recommended OM2210 Coherent Receiver calibration source model option Opt CC 2 C band lasers OM2210 Opt NL To be able to fully calibrate the receiver with Opt CC OM2210 Opt CC To be able to fully calibrate the receiver with Opt CC or a 3rd party C band receiver Opt LL 2 L band lasers OM2210 Opt NL To be able to fully calibrate the receiver with Opt LL OM2210 Opt LL To be able to fully calibrate the receiver with Opt LL or a 3rd party C band receiver Opt CL 1 each C band and L band lasers OM2210 Opt CL To be able to fully calibrate the receiver with Opt CL Opt NL no lasers Both of the following instruments are required OM2210 Opt CL To be able to fully calibrate the receiver with Opt CL OM2012 Opt CL Provides lasers sources required for calibration of receiver Upgrade options OM1106 OM11UP QAM Adds QAM and other software demodulators OM11UP MCS Adds multi carrier superchannel support OM4006D OM40DUP CC Replaces OM4006 lasers with 2 C band lasers OM40DUP LL Replaces OM4006 lasers with 2 L band lasers OM40DUP CL Replaces OM4006 lasers with 1 C band laser and 1 L band lase
6. 527 6 to 1565 5 nm L band 1570 01 to 1608 76 nm Number of FFT points 500k Minimum RBW 1 maximum oscilloscope time window Frequency accuracy 10 pm 14 www tektronix com Software requirements Supported platforms for the OM4000 software Computer with nVidia graphics card running US Windows 7 64 bit and MATLAB 201 1b 64 bit Computer with nVidia graphics card running US Windows XP 32 bit and MATLAB 2009a 32 bit The following platforms are supported by may not be able to use certain advanced graphics features such as color grade and 3D Tektronix 70000 Series Oscilloscopes running Windows 7 64 bit and MATLAB 201 1b 64 bit Computer with non nVidia graphics running US Windows 7 64 bit and MATLAB 2011b 64 bit Computer with non nVidia graphics running US Windows XP 32 bit and MATLAB 2009a 32 bit Please check with Tektronix when ordering for the most up to date detailed requirements including support for the latest releases of MATLAB software Please contact Tektronix for a price quote or to arrange a demonstration All product descriptions and specifications are subject to change without notice Power requirements Power requirements 100 115 230 V AC 50 to 60 Hz 1 power cable max 100 VA Physical characteristics Dimension Height 89 mm 3 5 in Width 432 mm 17 0 in Depth 298 5 mm 11 75 in Weight Net 11 8 kg 26 lb Shipping 15 9 kg 35 Ib Environmental characteristics does not include oscilloscope Temp
7. Horiz 50 GHz Div Multi carrierSpectrumx amp Superchannel spectrum Automated measurements Once the superchannel is configured the system can take measurements on each channel without further intervention by the user The OUI automatically tunes the OM4106D local oscillator takes measurements at that channel re tunes to the next channel and so forth until measurements of the entire superchannel have been taken Results of each channel are displayed in real time and persist after all measurements are made for easy comparison 10 www tektronix com Integrated measurement results All of the same measurement results that are made for single channels are also available for individual channels in a superchannel configuration Additionally multi carrier measurement results are available side by side for comparison between channels Visualizations such as eye diagrams constellation diagrams and optical spectrum plots can be viewed a single channel at a time or with all channels superimposed for fast comparison For separating channels in a multi carrier group several different filters can be applied including raised cosine Bessel Butterworth Nyquist and user defined filters These filters can be any order or roll off factor and track the signal frequency The OM4106D is part of a complete coherent optical test system Tektronix is the only test and measurement vendor that can offer a complete coherent optical test system from s
8. M BPSK PM QPSK PM 8 16 32 64 QAM PM Offset QPSK PM 8 PSK Any PRBS or user supplied pattern Contact factory for new modulation formats Control Built in Ethernet interface OM4000 Series Coherent Receiver Optical input C band 1530 to 1570 nm L band 1570 to 1610 nm Optional C and L band 1530 to 1610 nm Optional Maximum input power 15 dBm Maximum input power damage 20 dBm level Polarization extinction ratio gt 35 dB Optical local oscillator CW output 14 5 dBm poer C band 1527 6 to 1565 5 nm L band 1570 01 to 1608 76 nm Optional Electrical bandwidth OM4106D 33 GHz OM4006D 23 GHz www tektronix com 13 OM4006D OM4106D OM4000 Series Coherent Receiver Optical phase angle of IQ mixer 90 1 after correction Skew after correction 1 ps External local oscillator input Optical input wavelength range C band 1530 to 1570 nm L band 1570 to 1610 nm Optional Suggested external local oscillator 7 to 15 dBm input power range Maximum input peak power 20 dBm damage level Instantaneous linewidth lt 5 MHz Local oscillator Wavelength range C band 1527 6 to 1565 5 nm L band 1570 01 to 1608 76 nm Minimum wavelength step 10 GHz Minimum frequency step 100 MHz Absolute wavelength accuracy 10 pm Linewidth short term 100 kHz Sidemode suppression ratio 55 dB High resolution spectrometer Maximum frequency span LO frequency oscilloscope bandwidth LO Wavelength Range C band 1
9. TLAB is a registered trademark of MathWorks www tektronix com 1 OM4006D OM4106D OM4000 Series instrument flexibility The OM4000 is unique in the industry in that it works with both real time and equivalent time oscilloscopes This unprecedented architecture allows the user to get the benefits of either acquisition format all with a single CLSA For customers whose analysis requires a high sample rate using the CLSA with a real time oscilloscope such as the Tektronix DPO73304D may be optimal For customers whose analysis requires high vertical resolution such as modulator characterization an equivalent time oscilloscope may be the most beneficial Using a Tektronix oscilloscope solution of sufficient bandwidth provides bit rate analysis that exceeds 240 Gb s OM4000 Series user interface OUI The common thread through the Coherent Lightwave Signal Analyzer product line is the OUI which controls the operation and display of data Color grade persistence and color key options are available to help you visualize the data In the figure the horizontal transitions are more rare than the vertical transitions due to the relative timing of the IQ data sequence upper middle of figure The other polarization constellation is shown in color grade with only the symbol points lower middle Color grade is also available for the eye diagram bottom right This OUI can also be ordered separately without the OM4000 for to analyze dat
10. Tektronix L Coherent Lightwave Signal Analyzer OM4000 Series Datasheet Key features Coherent lightwave signal analyzer architecture is compatible with both real time and equivalent time oscilloscopes Complete coherent signal analysis system for polarization multiplexed QPSK offset QPSK QAM differential BPSK QPSK and other advanced modulation formats Displays constellation diagrams phase eye diagrams Q factor Q plot spectral plots Poincar Sphere signal vs time laser phase characteristics BER with additional plots and analyses available through the MATLAB interface Measures polarization mode dispersion PMD of arbitrary order with most polarization multiplexed signals Precise coherent receiver hardware provides minimal variation over temperature and time for a high degree of accuracy and high stability polarization diverse optical field detection Highly linear photo detection allows operation at high local oscillator and signal power levels to eliminate electrical amplification An integrated pair of ECDL tunable lasers for use as a local oscillator and another for self test Both lasers have industry best linewidth and tuning range for any wavelength within the band Coherent lightwave signal analyzer software tolerates gt 5 MHz instantaneous signal laser linewidth compatible with standard network tunable sources such as DBR and DFB lasers No laser phase or frequency locking req
11. a Point 49 An AR RIY 137 19 Annotated measurement table from OM4000 User Interface OUI Make adjustments faster The OUI is designed to collect data from the oscilloscope and move it into the MATLAB workspace with extreme speed to provide the maximum data refresh rate The data is then processed in MATLAB and the resulting variables are extracted for display Take control with tight MATLAB integration Since 100 of the data processing occurs in MATLAB test engineers can easily probe into the processing to understand each step along the way R amp D labs can also take advantage of the tight MATLAB integration by writing their own MATLAB algorithms for new techniques under development Use the optimum algorithm Don t worry about which algorithm to use When you select a signal type in our OUI for example PM QPSK the software applies optimal algorithm to the data for that signal type Each signal type has a specially designed signal processing approach that is best for the application This means that you can get results right away Don t get stymied by laser phase noise Signal processing algorithms designed for electrical wireless signals don t always work well with the much noisier sources used for complex optical modulation signals Our robust signal processing methods tolerate enough phase noise to even make it possible to test signals which would traditionally be measured by differential or direct detection such
12. a with another coherent receiver system The data capture and analysis only version of the OUI software is called the OM1106 Marder J oat Sprare Fressen y w lt 4 f E fy amp 4 z d qq v be fo f HAM le SS Ger PA AMT be V PRES Ge NANUT is AER x OM4000 user interface OUI showing color grade graphics options Symbols can also be colored to a key indicating prior state Data shown is 112 Gb s PM QPSK OM4000 User Interface OUI showing display of select equivalent time measurements 2 www tektronix com Interaction between OM4000 Series user interface OUI and MATLAB The OUI takes information about the signal provided by the user together with acquisition data from the oscilloscope and passes them to the MATLAB workspace shown in Figure 3 A series of MATLAB scripts are then called to process the data and produce the resulting field variables The OUI then retrieves these variables and plots them Automated tests can be accomplished by connecting to the OUI or by connecting directly to the MATLAB workspace The user does not need any familiarity with MATLAB the OUI can manage all MATLAB interactions However advanced users can access the MATLAB interface internal functions to create user defined demodulators and algorithms or for custom analysis visualization OUI MATLAB OUI e Plot results eyes constellation diagrams Poincare sphere e Write analysis paramete
13. an specify the number of PMD orders to calculate Accuracy for 1st order PMD is 1 ps at 10 Gbaud There is no intrinsic limit to the CD compensation algorithm It has been used successfully to compensate for many thousands of ps nm Recording and payback You can record the workspace as a sequence of MAT files using the Record button in the Offline ribbon These files are recorded in a default directory usually the MATLAB working directory unless previously changed You can play back the workspace from a sequence of MAT files by first using the Load button in the Offline Commands section of the Home ribbon Load a sequence by marking the files you want to load using the Ctrl key and marking the filenames with the mouse You can also load a contiguous series using the Shift key and marking the first and last filenames in the series with the mouse Use the Run button in the Offline Commands section of the Home ribbon to cycle through the MAT files you recorded All filtering and processing you have implemented occurs on the recorded files as they are replayed Offline Home Calibrate Loop Offline Data Record Load Run Stop i i Workspace record and playback Offline Commands Datasheet Multi carrier superchannel support Even as 100G coherent optical systems are being deployed architectures for 400G and beyond are being proposed and developed One architecture gaining prominence is the superchannel The c
14. as DQPSK www tektronix com 3 OM4006D OM4106D Find the right BER Our Q plots are a great way to get a handle on your data signal quality Numerous BER measurements vs decision threshold are made on the signal after each data acquisition Plotting BER vs decision threshold shows the noise properties of the signal Gaussian noise will produce a straight line on the Q plot The optimum decision threshold and extrapolated BER are also calculated This gives you two BER values the actual counted errors divided by the number of bits counted as well as the extrapolated BER for use when the BER is too low to measure quickly Q plot Constellation diagrams Once the laser phase and frequency fluctuations are removed the resulting electric field can be plotted in the complex plane When only the values at the symbol centers are plotted this is called a Constellation Diagram When continuous traces are also shown in the complex plane this is often called a Phase Diagram Since the continuous traces can be turned on or off we refer to both as the Constellation Diagram The scatter of the symbol points indicates how close the modulation is to ideal The symbol points spread out due to additive noise transmitter eye closure or fiber impairments The scatter can be measured by symbol standard deviation error vector magnitude or mask violations Cons UCP i i BE Sphere Const PSphene Megurerett Veh Elongatan 23306 PhassAn
15. ce of their own device Supported measurements and display tools Datasheet Coherent optical receiver manufacturers can also use the OM5110 as the ideal transmitter with which to test their receiver s performance and prove functionality under best case conditions Then using an instrument such as the AWG70001A Arbitrary Waveform Generator optical impairments can be added to the signal to test the receiver under a wide range of real world scenarios As the demand for network bandwidth has increased new transmission schemes such as multi carrier superchannels are under investigation The OM5110 can function as the heart of a superchannel system Multiple optical carriers can be externally combined and used as the laser source to the OM5110 using the external signal input Tektronix offers external laser sources such as the OM2012 Tuneable Laser Source which can be used to create a superchannel system With such a configuration systems with aggregate data rates such as 400G 1Tb s and beyond can be created Characteristic Description Real time supported Equivalent time feature supported feature Constellation Diagram Constellation diagram accuracy including intradyne and demodulation X X error can be measured by the RMS error of the constellation points divided by the magnitude of the electric field for each polarization signal Constellation Elongation Ratio of constellation height to
16. cealing an improperly biased driver amp Color Grade with fine traces Color Key Constellation Points is a special feature that works when not in Color Grade In this case the symbol color is determined by the value of the previous symbol This helps reveal pattern dependence Here it shows that pattern dependence is to blame for the poor EVM on the other groups The modulator nonlinearity would normally mask this type of pattern dependence due to RF cable loss but here the improper modulator bias is allowing that to be transferred to the optical signal Color Grade Constellation www tektronix com 5 OM4006D OM4106D Color Key Constellation If the prior symbol was in Quadrant 1 current symbol is colored Yellow If the prior symbol was in Quadrant 2 upper left then the current symbol is colored Magenta If the prior symbol was in Quadrant 3 lower left then the current symbol is colored Light Blue Cyan If the prior symbol was in Quadrant 4 lower right then the current symbol is colored Solid Blue Eye diagrams Eye diagram plots can be selected for appropriate modulation formats Supported eye formats include Field Eye which is simply the real part of the phase trace in the complex plane Power Eye which simulates the eye displayed with a Tektronix oscilloscope optical input and Diff Eye which simulates the eye generated by using a 1 bit delay line interferometer As with the Constellation Plot you can right cl
17. cessing X X Setting Bit Error Ratio Measurements Number of counted bits symbols X X Number or errors detected X X Bit error ratio X X Differential detection errors X X Save acquisition on detected error X X Offline Processing Run software on a separate PC or on the oscilloscope X X 0 07 j 1 0 este StdDev Mag 0 01 Input Optical Signal Power dBm Constellation diagram accuracy including intradyne and demodulation error can be measured by the RMS error of the constellation points divided by the magnitude of the electric field for each polarization signal The following plot was measured on a 2 5 GBaud NRZ 1 pol QPSK transmitter using a Tektronix MSO72004 digitizer 12 www tektronix com Datasheet Specifications Values stated in the following tables are typical unless stated otherwise some values are oscilloscope limited Coherent Lightwave Signal Analyzer Maximum detectable baud rate at 60 Gbaud with Tektronix DPO73304D 2 Ch f 9 5 dB e 46 Gbaud with Tektronix DPO73304D 4 Ch 40 Gbaud with Tektronix DPO72004 Maximum detectable bit rate for 240 Gb s with Tektronix DPO73304D x2 PM QPSK at Q of 9 5 dB AEAN aE a OS 180 Gb s with Tektronix DPO73304D x1 160 Gb s with Tektronix DPO72004 Sample Rate 100 GS s with Tektronix DPO73304D 50 GS s with Tektronix DPO72004 Optical field uncertainty RMS 2 O E gain imbalance between land 0 1 dB Q Available modulation formats OOK 3 state OOK P
18. d L band OM4006D NL No lasers receiver calibrated over C and L band OM4006D EXT Adds external connections for reference laser Required for ET OM4006D QAM Adds QAM and other software demodulators OM4106D options OM4106D 33 GHz Coherent Lightwave Signal Analyzer requires choice of lasers OM4106D CC C band lasers receiver tested over C band OM4106D LL L band lasers receiver tested over L band OM4106D CL Coupled C and L band lasers receiver calibrated over Cand L band OM4106D NL No lasers receiver calibrated over C and L band OM4106D EXT Adds external connections for reference laser OM4106D QAM Adds QAM and other software demodulators OM4106D MCS Adds multi carrier superchannel support OM1106 options OM1106 OUI signal analysis software only OM1106 QAM Adds QAM and other software demodulators OM1106 MCS Adds multi carrier superchannel support Opt A0 North America power plug 115 V 60 Hz Opt A1 Universal Euro power plug 220 V 50 Hz Opt A2 United Kingdom power plug 240 V 50 Hz Opt A3 Australia power plug 240 V 50 Hz Opt A5 Switzerland power plug 220 V 50 Hz Opt A6 Japan power plug 100 V 110 120 V 60 Hz Opt A10 China power plug 50 Hz Opt A11 India power plug 50 Hz Opt A12 Brazil power plug 60 Hz www tektronix com 17 OM4006D OM4106D User manual options Opt LO English manual Service options Opt C3 Calibration Service 3 Years Opt C5 Calibration Service 5 Years Opt R3 Repair Service
19. erature Operating 10 35 C Storage 20 to 70 C noncondensing humidity Humidity 15 to 80 relative humidity noncondensing CAUTION Datasheet This device is a Class 1M laser product for use only under the recommended operating conditions and ratings specified in the data sheet Use of controls or adjustments or performance of procedures other than those specified in the data sheet may result in hazardous radiation exposure Invisible laser radiation Do not view the laser output from this device directly with optical instruments This device complies with 21CFR1040 10 except for deviations pursuant to Laser Notice No 50 dated June 24 2007 www tektronix com 15 OM4006D OM4106D Ordering information Models Model Option Description Receiver bandwidth C band lasers L band lasers Wavelength band included included OM4006D CC 23 GHz C band 23 GHz 2 0 1530 to 1570 nm Coherent Lightwave Signal Analyzer OM4006D LL 23 GHz L band 23 GHz 0 2 1570 to 1610 nm Coherent Lightwave Signal Analyzer OM4006D CL 23 GHz C and L band 23 GHz 1 1 1530 to 1610 nm Coherent Lightwave Signal Analyzer OM4106D CC 33 GHz C band 33 GHz 2 0 1530 to 1570 nm Coherent Lightwave Signal Analyzer OM4106D LL 33 GHz L band 33 GHz 0 2 1570 to 1610 nm Coherent Lightwave Signal Analyzer OM4106D CL 33 GHz C and L band 33 GHz 1 1 1530 to 1610 nm Coherent Lightwave Signal Analyzer Recommended conf
20. extinction ratio The software locks on each polarization signal The polarization states of the two signals are displayed on a circular plot representing one face of the Poincar sphere States on the back side are indicated by coloring the marker blue The degree of orthogonality can be visualized by inverting the rear face so that orthogonal signals always appear in the same location with different color So Blue means back side negative value for that component of the Stokes vector X means X tributary O means Y tributary and the Stokes vector is plotted so that left down blue are all negative on the sphere InvertedRearFace Checking this box inverts the rear face of the Poincar sphere display so that two orthogonal polarizations will always be on top of each other a SnalysisParameters gt x PSphere Poincar Sphere window Impairment measurement and compensation When studying transmission implementations it is important to be able to compensate for the impairments created by long fiber runs or optical components Chromatic Dispersion CD and Polarization Mode Dispersion PMD are two important linear impairments that can be measured or corrected by the OM4000 software PMD measurement is based on comparison of the received signal to the back to back transmitter signal or to an ideal signal This produces a direct measure of the PMD instead of estimating based on adaptive filter behavior The user c
21. f these measurements is shown in the figure Datasheet Mean Min Max StdDev Xconst Symbol Std Dev O 0886vmwW O0 0886imwW 0 0833 mWw 0 0912imwWw 0 00208VmW 19 Xconst Symbols Displayed 3942 4101 3905 4268 132 19 Xconst Mask Violations 6 6 6 7 0 19 Xconst EVM Average 8 8 8 6 8 2 8 9 0 23 19 Xconst Magnitude 1 482vmW 1 4395vmW 1 373 mW 1 505vmwW 0 03873vmW 19 Xconst Phase Angle 94 deg 90 deg 85 deg 94 deg 3 2 deg 19 Xconst Bias Imag 0 12 0 12 0 13 0 12 0 0029 19 Xconst Bias Real 0 011 0 011 0 012 0 011 0 00028 19 Xconst IQ Imbalance 0 9946 0 9976 0 9534 1 046 0 02677 19 X I Undershoot 0 79 0 75 0 72 0 79 0 023 19 X I Overshoot 0 86 0 86 0 82 0 9 0 022 19 X I Falltime 45 ps 47 ps 45 ps 49 ps 1 3 ps 19 X I Risetime 49 ps 47 ps 45 ps 50 ps 1 5 ps 19 X I Skew 0 027 ps 0 028 ps 0 027 ps 0 029 ps 0 00082 ps 19 X I Crossing Point 50 50 48 52 14 19 X I Rail 1 Std Dev O 0873vmwWw 0 0904vmwWw O0 0863vmwW 0 0949imwW 0 00244 mW 19 X I Rail 0 Std Dev 0 0838vmwW O0 0868imwW 0 0828 mwWw 0 0911lvmwW 0 00234VmW 19 X I Eye Height 2 04 mW 2 02 mW 1 96 mW 2 11 mW 0 053VmwW 19 X I Q Factor 21 dB 21 dB 20 dB 22 dB 0 61 dB 19 X Q Undershoot 0 71 0 73 0 69 0 76 0 021 19 X Q Overshoot 0 85 0 87 0 83 0 91 0 025 19 X Q Falltime 47 ps 47 ps 45 ps 50 ps 1 3 ps 19 X Q Risetime 47 ps 48 ps 45 ps 50 ps 1 3 ps 19 X Q Skew 0 054 ps 0 056 ps 0 054 ps 0 059 ps 0 0014 ps 19 X Q Crassin
22. gle deg 63 3461 5 455 575 Res kas 5 D0336 Magnaude Constellation diagram 4 www tektronix com Constellation measurements Measurements made on constellation diagrams are available on the fly out panel associated with each graphic window The measurements available for constellations are described below Constellation measurements Measurement Description Elongation The ratio of the Q modulation amplitude to the modulation amplitude is a measure of how well balanced the modulation is for the and Q branches of a particular polarization s signal Real Bias Expressed as a percent this says how much the constellation is shifted left or right Real In phase bias other than zero is usually a sign that the In phase Tributary of the transmitter modulator is not being driven symmetrically at eye center Imag Bias Expressed as a percent this says how much the constellation is shifted up or down Imaginary Quadrature bias other than zero is usually a sign that the Quadrature Tributary of the transmitter modulator is not being driven symmetrically at eye center Magnitude The mean value of the magnitude of all symbols with units given on the plot This can be used to find the relative sizes of the two Polarization Signals Phase Angle StdDev by Quadrant The transmitter I Q phase bias It should normally be 90 The standard deviation of symbol point distance from the mean symb
23. ick to choose color options as well The Field Eye diagram provides the following measurements CE Eye db dB Eve Hecht Rad Std Dew Radi Std Dew 15 68 dB 2S 01974 02114 15 83 dB 2512 01989 02072 15 87 dB 2495 01994 02022 Summary i F Field eye diagram Field eye measurements Measurement Description Q dB Computed from 20 x Log10 of the linear decision threshold Q factor of the eye Eye Height The distance from the mean 1 level to the mean 0 level units of plot Rail0 Std Dev The standard deviation of the 0 level as determined from the decision threshold Q factor measurement Rail1 Std Dev The standard deviation of the 1 level as determined from the decision threshold Q factor measurement In the case of multilevel signals the above measurements are listed in the order of the corresponding eye openings in the plot The top row values correspond to the top most eye opening The above functions involving Q factor use the decision threshold method described in the paper by Bergano When the number of bit errors in the measurement interval is small as is often the case the Q factor derived from the bit error rate may not be an accurate measure of the signal quality However the decision threshold Q factor is accurate because it is based on all the signal values not just those that cross a defined boundary 3 N S Bergano F W Kerfoot C R Davidson Margin measure
24. ignal generation to modulation acquisition and analysis Coherent optical signal generation Tektronix offers several signal generation instruments capable of generating coherent optical waveforms The AWG70000 Series Arbitrary Waveform Generators AWG and the PPG3000 Series Programmable Pattern Generators offer the flexibility to choose the type of signal generation instrument suited to the test requirements The AWG70000 Series can reach sampling rates as high as 50GSa s with 10 bits vertical resolution This level of performance allows for the direct generation of IQ basebands signals required by modern coherent optical communication systems The arbitrary waveform generation capabilities of the AWG70000 Series makes it possible to create multi level signals such as 16QAM or 64QAM add impairments to a signal or to create waveforms that are pre compensated for the real world effects of the test system The PPG3000 Series can generate patterns up to 32 Gb s and offers 1 2 or 4 channels in a single instrument The patterns can be standard PRBS patterns or user defined Using a 4 channel pattern generator makes creating dual polarization Q waveforms very simple Coherent optical signal generation is one of the more demanding applications for an AWG The requirements in terms of number of channels sampling rate bandwidth record length and timing and synchronization quality can be only met by the highest performance instruments such a
25. igurations Oscilloscope type Receiver model Receiver options Receiver bandwidth Recommended Oscilloscope bandwidth oscilloscope model Real time systems OM4006D Recommended Opt CC 23 GHz DPO DSA72504C 25 GHz Opt QAM Opt TSI OMRACK OM4106D Recommended Opt CC 33 GHz DPO DSA73304D 33 GHz Opt QAM Opt TSI OMRACK Equivalent time 30 GHz OM4006D Recommended Opt CC 23 GHz DSA8300 with Opt 30 GHz systems Opt QAM Opt TSI ADVTRIG and 2 each OMRACK Required Opt 80E07 EXT OM4106D Recommended Opt CC 33 GHz DSA8300 with Opt 60 GHz Opt QAM Opt TSI ADVTRIG and 2 each OMRACK Reauired Opt 80E09 EXT OM1106 Coherent Lightwave Signal Analyzer software A stand alone software only tool that can perform all the data acquisition analyses filtering and display of the OM4000 system using the customer s polarization diverse coherent receiver OM2210 Coherent Receiver calibration source See Tektronix OM2210 data sheet for more detail The OM2210 can be used to maintain calibration of the OM4000 Series hardware or to characterize 3rd party receivers 16 www tektronix com Datasheet Instrument options Power plug options OM4006D options OM4006D 23 GHz Coherent Lightwave Signal Analyzer requires choice of lasers OM4006D CC C band lasers receiver tested over C band OM4006D LL L band lasers receiver tested over L band OM4006D CL Coupled C and L band lasers receiver calibrated over Can
26. lysis parameters Parameter Description Frequency Clock recovery is performed in software so only a frequency range of expected clock frequencies is required Signal Type The signal type such as PM QPSK determines the algorithm used to process the data Specifying the known PRBS or user pattern by physical tributary permits error counting constellation orientation and two stage phase estimation Data Patterns User patterns may be assigned in the MATLAB window shown here The data pattern can be input into MATLAB or found directly through measurement of a high SNR signal Signal spectra An FFT of the corrected electric field vs time can reveal much about the data signal Asymmetric or shifted spectra can indicate excessive laser frequency error Periodicity in the spectrum shows correlation between data tributaries The FFT of the laser phase vs time data can be used to measure laser phase noise signal Spectrum LaserPhaseSpectrumaA 4 Vert 1 000E 001 dB Div Horiz 1 000E 000 GHz div 10 dB Div 0 00 AH Ref Level dB 1 GHz div Res Bandwidth 25 1584 MHz Laser Phase Spectrum window 8 www tektronix com Poincare Sphere Polarization data signals typically start out well aligned to the PM fiber axes However once in standard single mode fiber the polarization states will start to drift However it is still possible to measure the polarization States and determine the polarization
27. ments in optical amplifier systems IEEE Phot Tech Lett 5 no 3 pp 304 306 1993 6 www tektronix com Additional measurements available for nonoffset formats Measurement Description Overshoot The fractional overshoot of the signal One value is reported for the tributary and for a multilevel QAM signal it is the average of all the overshoots Undershoot The fractional undershoot of the signal overshoot of the negative going transition Risetime The 10 90 rise time of the signal One value is reported for the tributary and for a multilevel QAM signal it is the average of all the rise times Falltime The 90 10 fall time of the signal Skew The time relative to the center of the power eye of the midpoint between the crossing points for a particular tributary Crossing Point The fractional vertical position at the crossing of the rising and falling edges Measurements vs Time In addition to the eye diagram it is often important to view signals versus time For example it is instructive to see what the field values were doing in the vicinity of a bit error All of the plots which display symbol center values will indicate if that symbol is errored by coloring the point red assuming that the data is synchronized to the indicated pattern The Measurement vs Time plot is particularly useful in this way as it helps to distinguish errors due to noise pattern dependence or pattern errors
28. nstrument serial number DPOACQSYNC Multi oscilloscope synchronization kit OMINSTALL AMR On site OM series install for the Americas OMINSTALL JPN On site OM series install for Japan OMINSTALL EMEA On site OM series install for Europe Middle East and Africa OMINSTALL APAC On site OM series install for Asia Pacific OM5110 46 GBaud Multi Format Optical Transmitter OM2210 Coherent Receiver Calibration Source OM2012 Tunable Laser Source OM1106 Coherent Lightwave Signal Analyzer Software included with the OM4106D Tektronix is registered to ISO 9001 and ISO 14001 by SRI Quality System Registrar www tektronix com 19 OM4006D OM4106D ASEAN Australasia 65 6356 3900 Austria 00800 2255 4835 Balkans Israel South Africa and other ISE Countries 41 52 675 3777 Belgium 00800 2255 4835 Brazil 55 11 3759 7627 Canada 1 800 833 9200 Central East Europe and the Baltics 41 52 675 3777 Central Europe amp Greece 41 52 675 3777 Denmark 45 80 88 1401 Finland 41 52 675 3777 France 00800 2255 4835 Germany 00800 2255 4835 Hong Kong 400 820 5835 India 000 800 650 1835 Italy 00800 2255 4835 Japan 81 3 6714 3010 Luxembourg 41 52 675 3777 Mexico Central South America amp Caribbean 52 55 56 04 50 90 Middle East Asia and North Africa 41 52 675 3777 The Netherlands 00800 2255 4835 Norway 800 16098 People s Republic of China 400 820 5835 Poland 41 52 675 3777 Portugal 80 08 12370 Republic of Korea 001 800 8255 2835 Russia amp CIS
29. ol in units given on the plot This is displayed for BPSK and QPSK EVM The RMS distance of each symbol point from the ideal symbol point divided by the magnitude of the ideal symbol expressed as a percent EVM Tab The separate EVM tab shown in the right figure provides the EVM by constellation group The numbers are arranged to correspond to the symbol arrangement This is ideal for setting Transmitter modulator bias For example if the left side groups have higher EVM than the right side adjust the In phase Transmitter modulator bias to drive the negative rail harder Mask Tab The separate Mask tab shown in the right figure provides the number of mask violations by constellation group The numbers are arranged to correspond to the symbol arrangement The mask threshold is set in the Engine window and can be used for pass fail transmitter testing Datasheet Color features The Color Grade feature provides an infinite persistence plot where the frequency of occurrence of a point on the plot is indicated by its color This mode helps reveal patterns not readily apparent in monochrome Note that the lower constellation groups of the example below have higher EVM than the top groups In most cases this indicates that the quadrature modulator bias was too far toward the positive rail This is not evident from the crossing points which are approximately correct In this case an improperly biased modulator is con
30. onfigurations of superchannels vary considerably Some proposals call for 400G to be achieved by 2 carriers of DP 16QAM Other proposals are for 500 Gb s consisting of 10 or more carriers of DP QPSK Some of these carriers are arranged on a standard ITU carrier grid while others support 12 5 GHz grid less layouts Clearly flexible test tools are needed for such next generation systems Option MCS to the OM4106D and OM1106 offers the complete flexibility to carrier out such tests Multicarrier Setup Preset Default New Delete Frequency mode Relative Absolute Frequency Prefered Channel i LO i Include 1 193 40 193 40 2 193 45 193 45 3 193 50 193 50 4 193 55 193 55 5 193 60 193 60 6 193 72 193 72 7 193 85 193 85 i nn AT ns nT Fl Multi carrier setup Multicarrier Measurements Measurement _ Channel 1 Channel2 Channel3 Channel4 Channel5 Unt x Eye X Q Q Factor 15 473 16 526 14 576 16 350 14 654 dB X Q Eye Height 31 528 31 555 31 530 31 551 31 574 vmw H X Q Rail 0Std Dev 2 644 2 769 2 691 2 591 2 438 vmw i X Q Rail 1Std Dev 2 665 2 765 2 661 2 667 2 753 ymw X I Q Factor 21 796 20 111 22 668 21 419 22 648 dB X I Eye Height 28 743 28 504 28 658 28 515 28 661 vmw X I Rail 0Std Dev 1 239 1 216 1 043 1 281 1 161 ymw im X I Rail 1Std Dev 1 099 0 901 1 131 1 283 1 040 vmw yY Eye X Const Y Const Yconst IQ Imbalance 1 006 1 006 1 006 1 007 1 006
31. r OM40DUP EXT Adds external connections for reference laser OM40DUP 4006D Upgrades OM4006 any model to OM4006D OM40DUP 4106D Upgrades OM4006 any model to OM4106D OM4106D OM41DUP QAM Adds QAM and other software demodulators OM41DUP CC Replaces OM4106 lasers with 2 C band lasers OM41DUP LL Replaces OM4106 lasers with 2 L band lasers OM41DUP CL Replaces OM4106 lasers with 1 C band laser and 1 L band laser OM41DUP EXT Adds external connections for reference laser OM41DUP 4106D Upgrade an OM4106B OM3105A or OM3105B to an OM4106D OM41DUP TSI Adds integration with Tektronix oscilloscope 18 www tektronix com Datasheet Standard accessories OM4106D OM4006D standard accessories OM4106D OM4006D User Manual 071 3184 xx Power cable Type depends on ordered power cord option RF Cable 2 92mm 4 174 6229 xx Ethernet cable 174 6230 xx Patch Cord Fiber 8 Opt EXT 174 623 1 xx Related products Programmed HASP key 650 564 2 xx Programmed USB Flash Drive 650 5643 xx Calibration and warranty Calibration interval 1 year Accessories Recommended accessories OMCABLE Replacement OM cable kit OMCABLE9 Set of 4 9 semi rigid cables Required for 2 oscilloscope systems OMDONGLE Replacement OM license dongle requires software license key number OMRACK Tabletop mounting rack for OM4000 Series OMTRAIN On site training and or installation for OMxxxx products OMADDLSW Additional set of Coherent Lightwave Signal Analyzer Software requires OM4106D i
32. rence lasers is displayed in X X Measurement panel www tektronix com 11 OM4006D OM4106D Characteristic Description Real time supported Equivalent time feature supported feature Poincar Sphere Polarizations of the Pol muxed signal tributaries are tracked and X displayed on the Poincar Sphere PER is measured Signal Quality EVM Q factor and mask violations Tributary Skew A time offset for each tributary is reported in the Measurement panel X X CD Compensation No intrinsic limit for offline processing FFT based filter to remove CD in X frequency domain based on a given dispersion value PMD Measurement PMD values are displayed in the Measurement panel for Polarization X multiplexed formats with a user specified number of PMD orders Oscilloscope and or Cable Delay Compensation Cable oscilloscope and receiver skew is corrected through interpolation 0 5 ns in the OUI Additional cable adjustment is available using the oscilloscope Ul Oscilloscope Skew Adjustment Equivalent time oscilloscope skew is adjusted using the Delay feature in 100 the supported sampling head plug ins Calibration Routines Receiver Skew DC Offset and Path Gain Mismatch Hybrid angle and X X state of polarization are factory calibrated Data Export Formats MATLAB other formats available through MATLAB or ATE interface X X PNG Raw Data Replay with Different Parameter Movie mode and repro
33. rs that may result from a laser phase jump Once the field variables are calculated they are available for retrieval and display by the OUI At each step the best algorithms are chosen for the specified data type requiring no user intervention unless desired scope sample rate gt symbol ApplyPhase ApplyPhase center _ i E E ee EstimateClock EstimateSOP EstimatePhase AlignTribs EstimatePhase count bit errors Q factor scope const params record continuous m mal ie a E field ApplyPhase ClockRetime ClockRetime scope sample rate gt N x symbol rate Data flow through the Core Processing engine Get up and running fast with the easy to use OUI The user interface for the Coherent Lightwave Signal Analyzer is called the OUI The OUI allows you to easily configure and display your measurements and also provides a means of software control for third party applications using WCF or NET communication It can also be controlled from MATLAB or LabVIEW The following image shows a QAM measurement setup The plots can be moved docked or resized You can close or create plots to display just the information you need O E mw QAM measurements on the OM4000 User Interface OUI In addition to the numerical measurements provided on the plots the measurements are also summarized on the Measurements window where Statistics are also displayed An example of some o
34. rs to MATLAB workspace e Clock recovery e Polarization estimation e Acquire oscilloscope data e Phase estimation e Report bit errors e Report Q factors constellation parameters Ambiguity resoluti e Write data to MATLAB TUR ere workspace e 2nd phase estimate e Count bit errors e Calculate constellation parameters Vblock SigType Freq Window etc zXSym ZYSym ZX ZY DecTh etc OUI MATLAB data flow Signal processing approach For real time sampled systems the first step after data acquisition is to recover the clock and retime the data at 1 sample per symbol at the symbol center for the polarization separation and following algorithms shown as upper path in the figure The data is also re sampled at 10X the baud rate user settable to define the traces that interconnect the symbols in the eye diagram or constellation shown as the lower path The clock recovery approach depends on the chosen signal type Laser phase is then recovered based on the symbol center samples Once the laser phase is recovered the modulation part of the field is available for alignment to the expected data for each tributary At this point bit errors can be counted by looking for the difference between the actual and expected data after accounting for all possible ambiguities in data polarity The software selects the polarity with the lowest BER Once the actual data is known a second phase estimate can be done to remove erro
35. s the Tektronix AWG70000 series The unique capability of generating ideal or distorted signals and the ease to add new modulation schemes and signal processing algorithms without the need to add any extra hardware make AWGs an ideal tool for coherent optical communication research and development Coherent optical modulation the OM5110 Engineers need instrument grade optical signal sources to test the latest 100G 400G and 1Tb s coherent optical products The Tektronix OM5110 Multi format Optical Transmitter provides the flexibility to modulate all the most common coherent optical formats at rates up to 46 GBaud The OM5110 Multi Format Optical Transmitter is a C and L Band transmitter capable of modulating the most common coherent optical modulation formats such as PM QPSK and PM 16QAM When combined with a signal source such as the AWG70001A Arbitrary Waveform Generator or the PPG3204 32 Gb s Pattern Generator it offers a complete coherent optical test signal generation system For coherent optical transmitter or transceiver manufacturers the OM5110 may be used as a golden reference against which to compare module designs The OM4106D optical modulation analyzer can be used to measure the performance of a transmitter under development and then compared against the OM5110 reference transmitter The flexibility to automatically or manually set all amplifier and modulator bias points provides the user to simulate less than ideal performan
36. uired Smart polarization separation follows signal polarization User access to internal functions with a direct MATLAB interface The OM4000 Coherent Lightwave Signal Analyzer CLSA is a 1550 nm C Be Tamils aCe o AVANADE ANONO SUETEL and L band fiber optic test system for visualization and measurement of Superior user interface offers comprehensive visualization for ease of complex modulated signals offering a complete solution to testing both use combined with the power of MATLAB coherent and direct detected transmission systems The CLSA consists of a polarization and phase diverse receiver and analysis software enabling ee Ione AAA EEA ANE iene wa Mea simultaneous measurement of modulation formats important to advanced and OM4000 series products fiber communications including polarization multiplexed PM QPSK The Multi carrier software option allows user definable superchannel setup CLSA software performs all calibration and processing functions to enable real time burst mode constellation diagram display eye diagram display Poincare sphere and bit error detection Superchannel configuration allows user to define number of channels channel frequency and channel modulation format Test automation acquires complete measurements at each channel Integtrated measurement results allow easy channel to channel comparisons 1 Certain features may be available only when used with Tektronix oscilloscopes 2 MA
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