Hi!
Could You help me once again with the slcprofile of POSSUM simulator?
I got instructions from you how to define our own slice profile for
POSSUM simulator.
I created one according to the instructions and verified it by our fMRI
technician. I have tested it with our own data as well as the default
data from POSSUM. It won't work. The same simulation with the possum
defaults works, but when I change the slcprofile to our own the output
is a mess.
Earlier instructions were following:
"The slice profile is simply truncated at a convenient point where
the amplitude is less than 0.3% of the maximum - since it needs
to be truncated at some arbitrary point. The frequency
difference is normalised as a percentage of the Larmor frequency. "
Should the profile have some defined length? Our profile has really
narrow band. Can that cause the problem?
Results are looking like this (all data is possum default, except the
slcprofile):
http://www.cs.tut.fi/~pajula2/possum.png
Waiting your answer,
--
Juha Pajula,
Research Assistant,
Methods and Models for Biological Signals and Images group of Signal
Processing department in Tampere University of Technology,
Finland
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