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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: 2516     Entry time: Fri Jan 15 12:04:26 2010     Reply to this: 2548
Author: Sanjit, mevans 
Type: Update 
Category: Adaptive Filtering 
Subject: Canceling noise again! 

 

OAF is successfully canceling noise again, thanks to Matt!

Here is a plot showing more than a factor of 10 noise reduction around 3Hz (similar to what we saw in the simulations)

The changes that has made it work are:

  • use of RANGER channel (with ACC_MC1_X and/or ACC_MC2_X)
  • mu = 0.01, tau = 1.0e-6, ntaps = 2000, nDown = 16
  • nDelay = 5 and nDelay = 7 both work (may not be so sensitive on delay at low frequencies)
  • Main changes: filter bank on the PEM channels (ASS_TOP_PEM_## filters: 0.1:0, 1:, Notch24, AA32)
  • Added the AI800 filter for upsampling in MC1 (should not matter)

 Matt suggested playing with the emphasis (EMPH) filters to cancel noise in different frequency bands.

 

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