The online GDS calibraiton filters were updated today to fix several bugs and add a few more corrections that were uncovered by the calibration group over the past week. The updates include the following changes:
1) Compensation for known IIR warping by Foton in the inverse sensing filter installed in the CALCS model. See DCC G1501013.
2) Fix bug in how digital response of AA/AI filters were called. (par.C.antialiasing.digital.response.ss -> par.C.antialiasing.digital.response.ssd andpar.A.antiimaging.digital.response.ss -> par.A.antiimaging.digital.response.ssd)
3) Additional compensation for OMCDCPD (par.C.omcdcpd.c).
The new filters were generated using
create_partial_td_filters_O1
checked into the calibration SVN under
aligocalibration/trunk/Runs/O1/Common/MatlabTools/
H1GDS_1128173232.npz
under aligocalibration/trunk/Runs/O1/GDSFilters/.
Attached are plots comparing the frequency response of the GDS FIR filters to the model frequency response.
There was a request to see how the inverse correction filters for the sensing chain were rolled off at high frequencies in these filters. This is done with a simple smooth roll-off above ~6500 Hz. I've attached plots that zoom in on the 5000-8192 Hz range to show how the rolloff causes the GDS filters to differ from the ideal inverse correction filters for the sensing chain.
