DAQ接收訊號後如何去除直流訊號

[michael_ku]

我要觀察訊號的頻譜圖得到他的頻率，但是一直會有一個很大的直流訊號，我在labview內加高通濾波器後一樣無法濾掉直流訊號，請問要如何解決?

[GerdW]

Hi Michael,

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@michael_ku wrote:

I want to observe the frequency spectrum of the signal to get its frequency, but there is always a large DC signal. Even after adding a high-pass filter in labview, I still cannot filter out the DC signal. How can I solve it?

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You could replace the DC value in the FFT spectrum data with zero...

You could subtract the mean of the time signal from this signal before the FFT...

[michael_ku]

How could I replace the DC value in the FFT spectrum data with zero?

I couldn't find it.

by the way, I tried second method its didn't work.

My problem is biased towards removing dynamic DC, is there any way to solve it.

I appreciate your help.

[GerdW]

Hi Michael,

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@michael_ku wrote:

My problem is biased towards removing dynamic DC, is there any way to solve it.

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Please attach a VI with some typical measurement data set to default in your charts…

What exactly is a "dynamic DC"?