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Entry  Fri Jan 15 12:04:26 2010, Sanjit, mevans, Update, Adaptive Filtering, Canceling noise again! OAF_15JAN2010.png
    Reply  Tue Jan 26 19:51:44 2010, Sanjit, rana, Update, Adaptive Filtering, OAF details C1ASS_TOP.pngC1SUS_SRM_XYCOM1.pngUntitled.png
       Reply  Mon Feb 1 18:31:00 2010, Sanjit, Update, Adaptive Filtering, OAF details 
          Reply  Mon Feb 1 21:51:12 2010, Sanjit, Update, Adaptive Filtering, OAF details 
       Reply  Fri Feb 5 00:52:55 2010, Sanjit, Update, Adaptive Filtering, OAF at 0.1-1.0 Hz OAF_04FEB2010_noOAF.pngOAF_04FEB2010.png
          Reply  Fri Feb 5 01:04:58 2010, Sanjit, Update, Adaptive Filtering, OAF at > 5Hz OAF_04FEB2010_highFreq.png
             Reply  Sat Feb 6 00:10:08 2010, Sanjit, Update, Adaptive Filtering, OAF at > 5Hz 
Message ID: 2572     Entry time: Fri Feb 5 01:04:58 2010     In reply to: 2571     Reply to this: 2575
Author: Sanjit 
Type: Update 
Category: Adaptive Filtering 
Subject: OAF at > 5Hz 

 

There is lot of coherence between the error signal and PEM channels at 5-100Hz. We had been applying a 1Hz low pass filter to all the GUR and RANGER channels for stability. I turned those off and OAF still works with mu=0.0025, this will give us some more freedom. Kind of annoying for testing though, it takes about 45min to adapt!

In any case, there is no significant improvement at high frequencies as compared to our usual OAF performance. Also, the low frequency improvement (see previous e-log) is lost in this set up. I think, we have to adjust the number of taps and channels to do better at high frequencies. Also, delay can be important at these frequencies, needs some testing.

 

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