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Altera_Forum
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14 years ago

FFT Megafunction problem - strange spikes

Hi, I use FFT IP Core (Quartus 9.1 SP2 / Quartus 11.1 SP2). I send sine-signal to sink pins and get fft-signal from source pins of core. Then I plot ABS, real and imag of my fft-signal in Matlab. ...
Altera_Forum's avatar
Altera_Forum
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14 years ago

> 20% THD and a similar DC component can't be explainced by a small deviation from full cycle. The FFT input signal must be seriously distorted somehow. Did you monitor the actual FFT input stream?