Determining frequency components of jitter
View Patent ↗A method of determining frequency components of jitter in a waveform is provided. The method includes strobing a waveform having a repetitive pattern. Forming a locally-in-order strobing scheme of a representative one of the repetitive pattern including subsets of locally-in-order strobes. Locating transition regions in the subsets of locally-in-order strobes. Determining random jitter associated for each transition region and determining jitter as a function of frequency.
1. A method of determining frequency components of jitter in a waveform, the method comprising:
strobing a waveform having a repetitive pattern;
forming a locally-in-order strobing scheme of a representative one of the repetitive pattern including subsets of locally-in-order strobes, wherein the locally-in-order strobings are based on undersampling strobing techniques that map strobes over a relatively large period of time to effective times within a test pattern;
locating transition regions in the subsets of locally-in-order strobes;
determining random jitter associated for each transition region; and
determining jitter within a specific frequency range.
2. The method of claim 1 , further comprising:
changing the frequency range by one of increasing the number of subsets of locally-in-order strobes and decreasing the number of subsets of locally-in-order strobing.
3. The method of claim 1 , further comprising:
adjusting a time period between locally-in-order strobes in each subset.
4. The method of claim 3 , wherein adjusting the time period between locally-in-order strobes in the subsets further comprises:
adjusting the total acquisition time to strobe the repetitive pattern.
5. The method of claim 3 , wherein adjusting the time period between locally-in-order strobes in the subsets further comprises:
adding additional strobes to the locally-in-order strobes; and
adjusting the number of strobes in the subset.
6. The method of claim 1 , wherein determining random jitter associated for each transition region further comprises:
determining the standard deviation of each transition region.
7. The method of claim 6 , further comprising:
calculating at least one of the average and root square average of all standard deviations.
8. The method of claim 1 , wherein determining jitter as a function of frequency further comprises:
determining an acquisition time of an associated transition region; and
associating the acquisition time associated with the transition region with a frequency.