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Timing Synchronization with Band Edge Filters

This article explores the synchronization of timing and carrier signals in digital modems using band edge filters. It discusses the importance of timing accuracy and presents various techniques for achieving synchronization. The article also covers the concept of phase offset and its correction using PLLs and frequency matched filters. Additionally, it explains the use of band edge filters in frequency locked loops and provides insights into eye diagrams and spectral analysis.

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Timing Synchronization with Band Edge Filters

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  1. Timing Synchronization with Band Edge Filters fred harris 11-15 September, 2017

  2. What The Customer Wants

  3. What the Customer Will Pay

  4. When the Customer wants it.

  5. The Size Customer Wants.

  6. Timing and Carrier Synchronization of Digital Modems

  7. Timing and Carrier Synchronization of Digital Modems Momma’s Middle name is Synchronizer

  8. A Common Line in Adventure Movies!

  9. Find Peak of Correlation Function Filter can’t answer the question: “Am I standing at the highest level?” She can only see the level where you are standing. A Better question to ask. and one she can answer is: “What’s the slope where I am standing?” Zero Slope Negative Slope Positive Slope f<fopt f=fopt f>fopt

  10. Derivative with Help of Nearby Neighbors (Early and Late)

  11. Maximizing Output of Correlation Receiver Same as Seeking Zero Derivative

  12. To Determine Which Direction is the Peak of the Correlator, Qualify the Derivative with Polarity of the Correlator Output

  13. Early-Late Gate Derivative

  14. Combining Early and Late Gates in a One Derivative Filter

  15. Slide Sampler to Input and Perform Timing Offset with Polyphase Digital Filter

  16. We can do the same for phase offsetswith a system that measures phase errors and adjusts a VCO to move the phase angle error towards 0. What is one to do when the phase offset is changing faster than the PLL can correct? You change loops to measure frequency offset and adjust VCO to move frequency error towards 0.

  17. Frequency Matched Filter Matched Filter Output Times Derivative Matched Filter Output

  18. Time and Frequency Response, Matched Filter and Frequency Derivative Matched Filter

  19. Frequency Matched FilterNon Data Aided Frequency Acquisition

  20. Band Edge Filter

  21. Spectra of Input Signal and Band Edge Filter Outputs

  22. Frequency Locked Loop with Band Edge Filters Maximum Likelihood Minimum Variance

  23. Frequency Locked PLL

  24. Spectra of Signals From Band Edges Combined to form Two New Signals

  25. Conjugate Product of Sum and Difference Band Edge Filters Imaginary Part, Sinusoid at Symbol Frequency. Phase Related to Time offset between Samples and Signal. Real Part DC Proportional to Energy Difference

  26. Equivalent Band Edge Options for Frequency Lock Loop

  27. Eye Diagrams of Matched Filter, Band-Edge Filter Sum, Difference, and Product

  28. Eye Diagrams of Matched Filter, Band-Edge Filter Sum, Difference, and Product with Timing Offset

  29. Spectra of SQRT Nyquist Shaped Modulation Signals over Range of Excess BW

  30. Eye Diagrams Matched Filter Output

  31. Cyclostationary Mean and Variance Eye Diagrams Magnitude Matched Filter Output

  32. Spectral Lines from Excess BW: MF(t) x dMF(t)* Modulation Noise

  33. Eye Diagrams Band Edge Difference Filter Output

  34. Cyclostationary Mean and Variance Eye Diagrams Magnitude Band Edge Difference Filter

  35. Spectra of BEsum(t) x BEdiff(t)* No Modulation Noise)

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