FFT Power spectrum mirroring

[nfisheremti]

hi, i'm trying to analyze run an fft analysis in the frequency domain. this seems to work fine, however when i graph the power spectrum, i see that the graph is mirrored around the center. how do i correct this?

thanks.

[protonLeah]

(How to) Upload a Workbook directly to the Forum
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[nfisheremti]

i have attached the a workbook (12.03.15 Run2.xls)
as you can see on the chart contained in the file it is mirrored around the center (~41kHz)

thanks for any assistance you can give me.

n