On 11/13/2012 10:38 PM, Tom Rondeau wrote:
On Tue, Nov 13, 2012 at 10:43 AM, Zhiwen He <address@hidden>
wrote:
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
_______________________________________________
Discuss-gnuradio mailing list
address@hidden
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
I did the attached.
Note that I've turned off the default window function in both the
forward and reverse transform
--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org
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