# FFT of optical Encoder signal?

Discussion in 'The Projects Forum' started by Nisha Sharma, Oct 28, 2009.

1. ### Nisha Sharma Thread Starter New Member

Oct 28, 2009
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Hello friends!!
I need some help about FFT. Actually I am taking a signal from optical encoder. which gives signal in square pulses form, i am measuring time period of each pulse via counter. Is it possible to take fft of this signal?? and analyze it?

2. ### Bernard AAC Fanatic!

Aug 7, 2008
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Sorry-but FFT escapes me. Deed definition.

3. ### SgtWookie Expert

Jul 17, 2007
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FFT = Fast Fourier transform
http://en.wikipedia.org/wiki/Fast_Fourier_transform

I suppose you might, but it would be rather difficult to glean a great deal of knowledge from doing so.

As you probably know already, a square wave is the sum of all of the odd harmonics of a fundamental frequency. The higher the bandwidth of the signal path, the more harmonics you'd have to sort through.

If your square waves were of irregular size, the FFT would simply look like broadband noise.