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Difference between revisions of "CW-Analyzer Tool"

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(Resync: Peak Detect)
(Resync: Peak Detect)
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Line up traces so peak (either max positive or max negative) within some given range of points all aligns.
 
Line up traces so peak (either max positive or max negative) within some given range of points all aligns.
 
For each trace the following must hold or the trace is rejected:
 
For each trace the following must hold or the trace is rejected:
- (1-valid limit) < (peak value from candidate trace) / (peak value from reference) < (1+valid limit)
+
-- (1-valid limit) < (peak value from candidate trace) / (peak value from reference) < (1+valid limit)
- If 'valid limit' is 0 then this is ignored, and all traces are kept.
+
-- If 'valid limit' is 0 then this is ignored, and all traces are kept.
  
 
=== Resync: Resample based on Zero-Crossing ===
 
=== Resync: Resample based on Zero-Crossing ===

Revision as of 11:19, 13 July 2016

Preprocessing Modules

Are filters that modify the traces from a given trace source (that can be another Preprocessing Module or the Trace Manager) and works as a new trace source to the next module in the chain (called trace observer).

Add Noise: Amplitude

Add random noise to the traces. Used for testing, has no use in actual analysis.

Add Noise: Time Jitter

Add random jitter. Used for testing, has no use in actual analysis.

Decimation: Clock Recovery

Attempts to 'recover' the clock by band-pass filtering, and then uses that to decimate to only points of interest. ****CURRENTLY NOT SUPPORTED****

Decimation: Fixed

Decimate (reduce the sample rate) by a fixed factor.

Digital Filter

Frequency specific filter.

Normalize

Normalize by standard deviation.

Resync: Cross Correlation

Use cross-correlation to detect shift between a 'reference trace' and every input trace. In practice the other resync methods seem to work better.

Resync: Peak Detect

Line up traces so peak (either max positive or max negative) within some given range of points all aligns. For each trace the following must hold or the trace is rejected: -- (1-valid limit) < (peak value from candidate trace) / (peak value from reference) < (1+valid limit) -- If 'valid limit' is 0 then this is ignored, and all traces are kept.

Resync: Resample based on Zero-Crossing

Deal with resampling 'bins' based on zero-crossing detection.

Sum of Difference

Minimize the 'Sum of Absolute Difference' (SAD), also known as 'Sum of Absolute Error'. Uses a portion of one of the traces as the 'reference'. This reference is then slid over the 'input window' for each trace, and the amount of shift resulting in the minimum SAD criteria is selected as the shift amount for that trace. See Sum of Absolute Difference (SAD) Pre-Processing for more information.