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Entry  Tue May 19 19:24:30 2015, rana, Update, PEM, Seismic BLRMS filters BLRMS_BP.pdfBLRMS_imp.pdf
    Reply  Mon Sep 7 19:46:46 2015, rana, Update, PEM, Seismic BLRMS filters T240_150907.png
       Reply  Wed Sep 9 15:45:11 2015, ericq, Update, PEM, Inverted STS filters in C1OAF 
Message ID: 11587     Entry time: Wed Sep 9 15:45:11 2015     In reply to: 11582
Author: ericq 
Type: Update 
Category: PEM 
Subject: Inverted STS filters in C1OAF 

Our online subtraction filters for PRC angle and MC length were trained on the raw ADC signals, so I've inverted the filters that Rana installed in the PEM filter banks in the OAF signal conditioning filter banks (C1:OAF-WIT_STS1X, etc.)

It's not perfect, since the inversion would be unstable, and thus needs a low pass. I used an ELP at 800Hz. The error in the inversion is then something like half a degree at 5Hz, which is the highest frequency we really ever subtract at. It should be ok.

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