40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Entry  Thu Jul 26 17:39:49 2012, Den, Update, digital noise, biquad key is working df2_bqf.pngdf2_bqf_spec.pngiir_psd_notch.pngiir_time_notch.png
    Reply  Thu Jul 26 21:31:44 2012, Den, Update, digital noise, online biquad works  df2_bqf_lp.pngdf2_bqf_lp_spec.png
    Reply  Fri Jul 27 14:30:49 2012, Jamie, Update, digital noise, biquad key is working 
       Reply  Mon Jul 30 14:24:25 2012, Den, Update, digital noise, biquad key is working lnf.png
Message ID: 7050     Entry time: Mon Jul 30 14:24:25 2012     In reply to: 7045
Author: Den 
Type: Update 
Category: digital noise 
Subject: biquad key is working 

Quote:

What is "DQF"?  Is that the biquad?  And what is the difference between DF1 and DF2?  Why don't you just write out the name, so it's more clear.

DQF - biquad form
DF1 - direct form 1
DF2 - direct form 2
LNF - low-noise form
 
The difference between them is described in Matt's slides G0900928-v1. I think, LNF coefficients are incorrect in the presentation
 
lnf.png
ELOG V3.1.3-