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</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt;">Dear Fieldtrip developers and users,<o:p></o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt;"><o:p> </o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;">Since a while I am
struggling with a question regarding the frequency range used in beamfomer,<o:p></o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><o:p> </o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;">The length of each data epoch is
1 second, resulting in <span lang="ZH-CN" style="font-family: ËÎÌå;">¡À</span>1Hz
frequency smoothing while performing ¡®mtmfft¡¯ method together with a hanning
taper. Nevertheless, when the frequency band of interest is
4~7Hz at sensor-level,<o:p></o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;">how to make the frequency range
as the frequency of interest in source analysis? At sensor level, the
permutation test offer a configuration setting for frequency average which
resolves the issue.<o:p></o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><o:p> </o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;">One possible solution, which I
have tried consisting of using ¡®dpss¡¯ taper instead of ¡®hanning¡¯ taper, setting
the frequency of interest to 5.5Hz, padding the epoch to 2s and setting the
tapsmofrq = 1.5. The resulting 5.5 <span lang="ZH-CN" style="font-family: ËÎÌå;">¡À</span>1.5Hz
is just the range needed. Is it a feasible way? If it is, will the setting of
padding influence the source analysis result to some degree?<o:p></o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><o:p> </o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;">The other possible solution I
have considered, is to average the output of frequency analysis, including
¡®powspctrm¡¯ and ¡®crsspctrm¡¯ across the selected range manually. Then the
average result from the frequency range will output to source analysis? Is this
correct?<o:p></o:p></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><i><span style="color: black;"><o:p> </o:p></span></i></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><span style="color: black;">Thanks
for your help,<o:p></o:p></span></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><span style="color: black;"><o:p> </o:p></span></p><font face="Times New Roman">
</font><p class="MsoNormal" style="margin: 0cm 0cm 0pt; -ms-text-autospace:;"><span style="color: black;">Chen<o:p></o:p></span></p><font face="Times New Roman">
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