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Presented by: Sergey Volkovich Vladimir Dibnis Spring 2011 Supervisor: Mony Orbach Slide 2 Jitter is a significant phenomena at high speed communication lines which strongly affects signal integrity. Therefore it is important to be able to artificially create different types of jitter in order to explore its implications and use it for educational purposes. Slide 3 To study the high speed channels jitter phenomena and its types To artificially create different types of jitter using Tabors Arbitrary Waveform Generator via a Matlab GUI To present the different jitter phenomena using the Agilent Infiniium Scope and analyze them with different methods Slide 4 Agilent Infiniium Scope Matlab GUI on PC LAN Cable Tabor WX2182 Arbitrary Waveform Generator Software Hardware SMA to BNC Cable Slide 5 Dual output configuration with independent waveform control Operational in each of the following modes: Function generator, Arbitrary waveform generator, Modulation generator, Sequence generator, Pulse generator 12 Bit vertical resolution 32M waveform memory 2 Vp-p into 50, double into open circuit Complex sequences link and loop segments in user- definable order Ethernet, USB and GPIB interfaces Slide 6 In order to create an arbitrary waveform we store coordinates in the devices memory and transfer them through a D/A to the oscilloscope according to the clock sampling rate, which is set to 2.1G points/s. The minimum points needed per data bit is 320. Therefore the maximum data bit rate is 6.56MHz according to the following formula: Data bit rate = sampling rate / segment length Slide 7 Total Jitter Deterministic Jitter Periodic Jitter Bounded Uncorrelated Jitter Data-Dependent Jitter Random Jitter Inter Symbol Interference Duty Cycle Disorder Jitter is a short term variation in a digital signal from its ideal value in time. Slide 8 Deterministic Jitter (DJ): noise with bounded values which is not normally distributed Periodic Jitter (PJ): has discrete frequency components Bounded Uncorrelated Jitter (BUJ): signal- independent and bounded in its distribution Data-Dependent Jitter (DDJ): signal-dependent Inter Symbol Interference (ISI): caused by near bits influence on the measured bit Duty Cycle Disorder (DCD): caused by different rise and fall times Random Jitter (RJ): signal-independent random noise, can be modeled by Normal distribution Slide 9 Eye Diagram:Time Interval Error Trend: Histogram:Bathtub Curve: Frequency Domain: Random Jitter Random & Periodic Jitter Periodic Jitter - SquaredPeriodic Jitter - Sinusoidal Slide 10 Receive the GUI parameters Create a signal matrix without a jitter Create the jittered data matrix according to the signal and total jitter effect matrices Create the total jitter effect matrix Send data to the waveform generator to be continuously generated Slide 11 Sinusoidal Periodic Jitter: Random Jitter: x = linspace(0, 2*pi,total_bits); effect_pj = sin(x); effect_rj = rj_mean + rj_stdev.*randn(1,total_bits); Bounded Uncorrelated Jitter: in the same method same as in RJ but when the values exceed the boundaries theyre being regenerated. Duty Cycle Disorder: by scanning the signal matrix we find where changes occur and insert a constant value to the corresponding place in the disturbance matrix. Inter Symbol Interference: by scanning the signal matrix we find where changes occur and the number of the identical preceding bits. We then calculate and insert a constant value to the corresponding place in the disturbance matrix according to the formula: Jitter Combinations: we sum the different disturbance matrices or calculate their weighted average. Slide 12 Slide 13 Eye Diagram: Jitter Size = 0.1UI = 20ns Slide 14 Bathtub Curve: Jitter Size = 0.1UI. It can be seen that the jitter is deterministic. Slide 15 Time Interval Error (TIE) Trend Squared: Jitter Size = 0.1UI = 20ns Slide 16 Time Interval Error (TIE) Trend Sinusoidal: Jitter Size = 0.1UI = 20ns Slide 17 Time Interval Error (TIE) Trend Triangular: Jitter Size = 0.1UI = 20ns Slide 18 Time Interval Error (TIE) Histogram - Squared: Jitter Size = 0.1UI = 20ns Slide 19 Time Interval Error (TIE) Histogram - Sinusoidal: Jitter Size = 0.1UI = 20ns Slide 20 Time Interval Error (TIE) Histogram - Triangular: Jitter Size = 0.1UI = 20ns Slide 21 Frequency Domain: Zoomed InSquared Slide 22 Eye Diagram: Standard Deviation = 5 Slide 23 Bathtub Curve Different Standard Deviations: Standard Deviation = 1Standard Deviation = 2 Slide 24 Time Interval Error (TIE) Trend: The trend isnt periodic due to the random nature of the jitter Slide 25 Frequency Domain: There are no discrete values due to the random nature of the jitter Slide 26 Time Interval Error (TIE) Histogram Different Standard Deviations: Standard Deviation = 1Standard Deviation = 5 Slide 27 Time Interval Error (TIE) Histogram Different Means: Standard Deviation = 1, Mean = 0.1UIStandard Deviation = 1, Mean = -0.1UI Slide 28 Eye Diagram Different Boundaries: Precedence Boundary = 0.05UIDelay Boundary = 0.05UI Slide 29 Time Interval Error (TIE) Histogram Different Distributions: Gaussian Distribution, Jitter Size = 0.2UIUniform Distribution, Jitter Size = 0.4UI Slide 30 Bathtub Curve Different distributions, bounded to 0.05UI: Gaussian Distribution, Standard Deviation = 5Uniform Distribution Slide 31 Rise Time Delay, Jitter Size = 0.2UIFall Time Delay, Jitter Size = 0.2UI Duty Cycle Disorder: Slide 32 Rise Time Delay, Jitter Size = 0.2UI Duty Cycle Disorder Random Signal: Slide 33 Inter Symbol Interference: Rise Time Delay, = 10 7% changeFall Time Delay, = 10 7% change Slide 34 DCD and ISI Combination: DCD Size = 0.1UI = 20ns, of ISI = 10 17% change Slide 35 Duty Cycle Disorder Bathtub Curve: DCD Size = 0.1UI = 20ns Slide 36 Inter Symbol Interference - Bathtub Curve : Random Signal, = 20Random Signal, = 5 Slide 37 Sinusoidal Periodic Jitter and Random Jitter Combination TIE Trend: Sinusoidal PJ Jitter Size = 0.1UI RJ Standard Deviation = 1 Sinusoidal PJ Jitter Size = 0.1UI RJ Standard Deviation = 3 Slide 38 Sinusoidal Periodic Jitter and Random Jitter Combination Bathtub Curve: Sinusoidal PJ Jitter Size = 0.1UI RJ Standard Deviation = 1 Sinusoidal PJ Jitter Size = 0.1UI RJ Standard Deviation = 3 Slide 39 Squared Periodic Jitter and Random Jitter Combination Histogram: Squared PJ Jitter Size = 0.1UI Without the Random Jitter Squared PJ Jitter Size = 0.1UI RJ Standard Deviation = 1 Slide 40 Sinusoidal Periodic Jitter and Random Jitter Combination Frequency Domain: Without the Random Jitter With the Random Jitter Slide 41 Bounded Uncorrelated Jitter and Random Jitter - Histogram: BUJ Boundaries = 0.05UI, BUJ Standard Deviation = 1, RJ Standard Deviation = 10 Slide 42 Inter Symbol Interference and Random Jitter Combination Bathtub Curve: Random Signal, of ISI = 3, Without the Random Jitter Random Signal, of ISI = 3, RJ Standard Deviation = 3 Slide 43 Sinusoidal Periodic Jitter and Duty Cycle Disorder Combination Eye Diagram: PJ Jitter Size = 0.2UI = 40ns, Without the Duty Cycle Disorder PJ Jitter Size = 0.2UI = 40ns, DCD Jitter Size = 0.2UI = 40ns Slide 44 We have studied the high speed channels jitter phenomena, its types and the different methods to measure and analyze it We have created a Matlab GUI that allows us to artificially create all the required jitter types, combine them and control their different parameters We have performed a profound analysis on all of the artificially created jitter types and their different combinations by measuring, analyzing and comparing them to the defined parameters Slide 45 We have learned that the signal generator combined with Matlab makes a very powerful tool for arbitrary signal creation and can be used as an educative tool The main limitation of the signal generator is the minimal number of points needed for creating a bit The generated wave could be used as an input for other circuits for further applications In future projects it is possible to recreate other phenomena using the same environment Slide 46