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Entry  Fri Sep 25 19:55:59 2009, Jenne, Update, Adaptive Filtering, Subtraction of the microseism using Adaptive Filtering! OAF_running_WORKING_25Sept2009.png
    Reply  Mon Sep 28 02:24:05 2009, rana, Update, Locking, MC1/3 Dewhitening found OFF: Turned back ON C1SUS_SRM_XYCOM1.pngUntitled.png
Message ID: 2004     Entry time: Fri Sep 25 19:55:59 2009     Reply to this: 2011
Author: Jenne 
Type: Update 
Category: Adaptive Filtering 
Subject: Subtraction of the microseism using Adaptive Filtering! 

[Rana, Jenne]

The OAF system did something useful today!  Attached is a plot.  Black is the reference (13 averages) with the OAF off.  Blue is the output of the OAF, and red is the reduced MC_L signal (13 averages).  If you turn tau and mu both to 0, it "pauses" the filter, but keeps the feedforward system working, so that you can take a long average to get a better idea of how well things are working. If you ramp down the output of the CORR filter bank, that lets you take a long average with the OAF "off", but doesn't mess up your nicely adapted filter.  The cyan and gold traces in the upper plot are 2 of the Guralp channels, so you can see the real seismic motion.

In the lower plot, you can see that the cyan and light green seismic channels have good coherence with IOO-MC_L (the names don't really mean anything right now...these 2 seismometer channels are the 2 Guralps' channels, one per end of the MC, which are aligned with the MC.)  The dark blue trace is the coherence between IOO-MC_L and the output of the OAF.

500 taps, delay=5, 2 Guralp channels (the ones aligned with the MC), tau~0.00001 (probably), and mu~0.01 or 0.005

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OAF_running_WORKING_25Sept2009.png
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