�� . �� : http://www.naic.edu/~phil/hardware/pdev/pdevgain/lpdfTypesCompare.html
�� : Thu Oct 3 23:53:28 2013
�� : Sat Mar 1 12:07:06 2014
��:
�� : spitzer space telescope

compare dlpf shapes

Compare DigLowPass filter shapes

03oct13

Jeff mock supplied 6 different types of filters to use with the high resolution mode of the mock spectrometer. They are:

rectangle
hamming
hanning
blackman
bartlett
triangle

The filters were generated with jeffs program (pnet_mkdlpf_coeff). Plots were made of the time domain voltage response as well as the frequency domain power response. A decimation of 10 was used for the filter decimation. this gave a filter length of 80 coeff.

The plots compare the filter shapes for these filter types (.ps) (.pdf)

Top: time domain voltage response. Each color is a different filter type
middle: spectral density reponse for each filter

db scale
the band edge is flagged at +/- .05

Bottom: blowup of the spectral density responsee.

SUMMARY.:

The frequency response of the various filter types are over plotted.
The rectangle has the narrowest response.

processing: x101.131003/lpdf/simDlpf.pro

<- page up
home_~phil