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Message ID: 11502     Entry time: Thu Aug 13 12:06:39 2015
Author: Jessica  
Type: Summary 
Category: IOO 
Subject: Better predicted subtraction did not work as well Online 

Yesterday I adjusted the preweighting of my IIR fit to the transfer function of MC2, and also managed to reduce the number of poles and zeros from 8 to 6, giving a smoother rolloff. The bode plots are pictured here:

The predicted IIR subtraction was very close to the predicted FIR subtraction, so I thought these coefficients would lead to a better online filter.

However, the actual subtraction of the MCL was not as good and noise was injected into the Y arm.

The final comparison of the subtraction factors between the online and offline data showed that the preweighting, while it improved the offline subtraction, needs more work to improve the online subtraction also.

Attachment 1: newBodeX.png  202 kB  | Hide | Hide all | Show all
newBodeX.png
Attachment 2: newBodeY.png  203 kB  | Hide | Hide all | Show all
newBodeY.png
Attachment 3: pred_Sub.png  153 kB  | Show | Hide all | Show all
Attachment 4: MCLSub.png  160 kB  | Hide | Hide all | Show all
MCLSub.png
Attachment 5: YarmSub.png  153 kB  | Hide | Hide all | Show all
YarmSub.png
Attachment 6: comparison.png  163 kB  | Hide | Hide all | Show all
comparison.png
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