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Entry  Fri Nov 30 02:40:44 2012, Den, Update, Adaptive Filtering, YARM yarm_oaf.png
    Reply  Fri Nov 30 11:49:24 2012, Koji, Update, Adaptive Filtering, YARM 
       Reply  Fri Nov 30 14:21:18 2012, rana, HowTo, Computer Scripts / Programs, The mystery of PDFs and you. As deep as the mystery of Rasputin. darm.pdf
       Reply  Fri Nov 30 22:11:50 2012, Den, Update, Adaptive Filtering, ARMS arms_oaf.pdf
          Reply  Sat Dec 1 00:13:16 2012, Den, Update, Adaptive Filtering, ARMS and MC arms_mcl_oaf.pdf
Message ID: 7764     Entry time: Fri Nov 30 02:40:44 2012     Reply to this: 7767
Author: Den 
Type: Update 
Category: Adaptive Filtering 
Subject: YARM 

I've applied FIR adaptive filter to YARM control. Feedback signal of the closed loop was used as adaptive filter error signal and OAF OUT -> IN transfer function I assumed to be flat because of the loop high gain at low frequencies. At 100 Hz deviation was 5 dB so I've ignored it.

I've added a filter bank YARM_OAF to C1LSC model to account for downsampling from 16 kHz to 2 kHz and put low-pass filter inside.

I've used GUR 1&2 XYZ channels as witnesses. Bandpass filters 0.4-10 Hz we applied to each of them. Error signal was filters using the same bandpass filter and 16 Hz 40 dB Q=10 notch filter. As an AI filter I used 32 Hz butterworth 4 order low-pass filter. Consequently, AI, bandpass and notch filters were added to adaptive path of witness signals.

I've used an FIR filter with 4000 taps, downsampling = 16, delay = 1, tau = 0, mu = 0.01 - 0.1. Convergence time was ~3 mins.


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