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Entry  Fri Nov 25 22:11:12 2011, Mirko, Update, CDS, Beware of fancy filter modules ChebyTST3.pngCheby.pngCoherenceCheby.pdfChebyAt16kHzBlackand2kHzRed.png
    Reply  Sat Nov 26 02:05:43 2011, Mirko, Update, CDS, Beware of fancy filter modules 
       Reply  Sat Nov 26 10:55:40 2011, rana, Update, CDS, Beware of fancy filter modules 
          Reply  Mon Nov 28 19:24:51 2011, Jenne, Update, CDS, Beware of fancy filter modules SUSPOS_ETMY_30and0_measured_vs_idealTF.pdfSUSPOS_ETMY_Cheby_measured_vs_idealTF.pdfSUSPOS_ETMY_30and0andCheby_measured_vs_idealTF.pdfSUSPOS_ETMY_30and0andCheby_compareCoherence.pdfSUSPOS_ETMY_30and0andCheby_compareCoherence.pdf
             Reply  Mon Nov 28 22:09:24 2011, rana, Update, CDS, Beware of fancy filter modules noise.pdf
                Reply  Tue Nov 29 15:30:01 2011, jamie, Update, CDS, location of currently used filter function 
                   Reply  Tue Nov 29 15:57:43 2011, Den, Update, CDS, location of currently used filter function 
Message ID: 6030     Entry time: Mon Nov 28 19:24:51 2011     In reply to: 6017     Reply to this: 6031
Author: Jenne 
Type: Update 
Category: CDS 
Subject: Beware of fancy filter modules 

[Rana, Jenne]

Some of the funniness is some kind of mysterious interaction between 2 filter modules in the filter banks.  Just FM1 (30:0.0) or just FM4 (Cheby, which is 2 cheby1's) has reasonable coherence.  Both FM1 and FM4 together doesn't do so well - the coherence goes way down.

Just FM1 (30:0.0)

SUSPOS_ETMY_30and0_measured_vs_idealTF.pdf

Just FM4 (Cheby)

SUSPOS_ETMY_Cheby_measured_vs_idealTF.pdf

 Both FM1 and FM4

SUSPOS_ETMY_30and0andCheby_measured_vs_idealTF.pdf

 All the coherences plotted together

SUSPOS_ETMY_30and0andCheby_compareCoherence.pdf

You'd think that the signal encounters FM1, gets filtered, and that result is the signal sent to the next active filter module, FM4, so the 2 filter modules shouldn't interact.  But clearly there's some funny business here since engaging both makes things crappy. 

Matlab investigations to replicate this behavior offline are in progress.

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SUSPOS_ETMY_30and0andCheby_compareCoherence.pdf
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