hello all,
When I use the fft blcok, it seems not right.
I build the test system like this: Square source -> IFFT -> FFT -> File Sink, when the input is 1, the output in the file sink is 1, and when the intput is 0, the output is random, sometimes 0, sometimes between -1 and 1.
Like this:
input:
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output:
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How should I do, so that the source data is the same as the sink data?
Thanks.
Heyutu
Hi Heyutu,
I just tried this right now and don't have a problem. This is my full graph:
sig_source (square wave) -> throttle -> stream_to_vector(fftsize) -> fft(fftsize, reverse) -> multiply_const(fftsize*[1/fftsize], fftsize) -> fft(fftsize, forward) -> vector_to_stream -> time sink
Tom