I used Foton to make up some new filters which will be used all over the project in order to downsample/upsample.
There will be 2 flavors:
- The first one will be a downsampling filter for use in the DAQ system.
Whenever you specify a sampling rate in the .ini files below the natural rate of the ADC,
the data will be downsampled using this filter (called ULYAW_0 in the plot). This one was
designed for flat bandpass and a 'good' bandstop but no care given to the phase shift.
- The second one will be used in the FE systems to downsample the ADC signal which is often
sampled at 64 kHz down to something manageable like 2k or 16k. This one was tweaked for
getting less phase lag in the 'control' band (usually 3x or so below Nyquist).
Here is the associated filter file:
# SAMPLING ULYAW 16384
# DESIGN ULYAW 0 zpk([0.512+i*1024;0.512-i*1024;2.048+i*2048;2.048-i*2048], \
# [515.838+i*403.653;515.838-i*403.653;318.182+i*623.506;318.182-i*623.506;59.2857+i*827.88; \
# 59.2857-i*827.88],0.988553,"n")
# DESIGN ULYAW 1 zpk([0.512513+i*1024;0.512513-i*1024;1.53754+i*2048;1.53754-i*2048], \
# [200+i*346.41;200-i*346.41;45+i*718.592;45-i*718.592],1,"n")
# DESIGN ULYAW 2 zpk([0.768769+i*1024;0.768769-i*1024;1.53754+i*2048;1.53754-i*2048], \
# [194.913-i*331.349;194.913+i*331.349;53.1611+i*682.119;53.1611-i*682.119],1,"n")
### ###
ULYAW 0 21 3 0 0 DAQAA 0.00091455950698073 -1.62010355523604 0.67259370084279 -1.84740554170818 0.99961738977942
-1.72089534598832 0.78482029284220 -1.41321371411946 0.99858678588255
-1.85800352005967 0.95626992044093 2.00000000000000 1.00000000000000
ULYAW 1 21 2 0 0 FEAA 0.018236566955641 -1.83622978049494 0.85804776530302 -1.84740518752455 0.99961700649533
-1.89200532023258 0.96649324616546 -1.41346289594856 0.99893883979950
ULYAW 2 21 2 0 0 ELP 0.015203943102927 -1.84117829296043 0.86136943504058 -1.84722827171918 0.99942556512240
-1.89339022414279 0.96048849609619 -1.41346289594856 0.99893883979950
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