r3 - 2015-06-06 - 13:25:07 - DurgeshPandeyYou are here: NTP >  Dev Web > GoogleSummerOfCode > GSoC2015ClockAlgorithms
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Study the usefulness of different clock models for NTP


The main goal of this project is to analyze the usefulness of different clock models for NTP, contributing for an enhanced performance. The goal is to use filtering techniques to analyze two issues. The first is a parameter that provides an explicit connection between the polling interval and the accuracy of the synchronization process. The second issue is a more sophisticated model for the performance of the clock on the local system and for the network delay. Different concepts (e.g. Allan Variance and it's application to determining the stability) related to clock statistics will also be studied.


Brief description of topics completed till now (After Community Bonding Period):

  1. Reviewed the articles that have been completed in community bonding period

  2. The concepts of the frequency Domain and time Domain

  3. Detailed study of these topics:

    1. Analysis of Time Domain data

    2. Study of method for calculated the range of “true” Allan Variance from the calculated estimate for a specific tau values

    3. Study of Spectrum Analysis and translation between spectral Density of frequency and Allan Variance

    4. Study of modified Allan Variance estimate for enhancing the knowledge of Allan Variance.

    5. Calculation of range of true Allan Variance from the estimated Allan Variance on the data series provided by Mentor and plotting the relation between Τ (tau) values and degree of freedom for each data series.

    6. Plotting the relation between Τ (tau) values on x-axis and estimated Allan variance, lower range of true Allan Variance, upper range of true Allan Variance on the Y-axis as calculated by the method studied in 2 (currently in progress).

    7. Preparing to work on the problem “Estimating the crystal oscillator drift in motherboard using temperature sensors” (started discussion)

Reference Articles for the Above study:

  1. Properties of Signal Sources and Measurement Methods by D.A. Howe, D.W. Allan and J.A. Barnes

  2. Frequency and Time- Their Measurement and Characterization By Samuel R. Stein

  3. Introduction of time and frequency Metrology

  4. Characterization of Frequency Stability: Analysis of the Modified Allan Variance and Properties of its Estimate


Date Task Description % Done
04-27 Community Bonding Students get to know mentors, read documentation, get up to speed to begin working on their projects. choice-yes
05-25 Coding Begins Students begin coding for their GSoC projects  
06-26 BO Midterm Evals Mentors and students can begin submitting mid-term evaluations.  
07-03 EO Midterm Evals Mid-term evaluations deadline.  
08-17 Wrap-up Suggested "Pencils Down" date. Take a week to scrub code, write tests, improve documentation, etc.  
08-21 Firm "Pencils Down" Mentors, students and organization administrators can begin submitting final evaluations to Google.  
08-28 Final Evaluation Final Evaluations Deadline  
08-28 Code Samples Students begin uploading code samples  
08-31 Final Results Final Results Announced  

Discussion and Comments

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elsedocx Week_1.docx manage 5.5 K 2015-06-06 - 13:18 DurgeshPandey  
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