[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Discuss-gnuradio] Spectrum_sense of a smaller banwidth
From: |
Eric Blossom |
Subject: |
Re: [Discuss-gnuradio] Spectrum_sense of a smaller banwidth |
Date: |
Tue, 10 Mar 2009 10:05:38 -0700 |
User-agent: |
Mutt/1.5.18 (2008-05-17) |
On Tue, Mar 10, 2009 at 03:33:32AM -0700, Adi85 wrote:
>
> Still getting an error!
> thank you in advance
>
> class topBlock(gr.top_block):
> > def __init__(self):
> > gr.top_block.__init__(self)
> >
> > fftsize = 256
> > udecim = 256
> >
> > mywin = window.blackmanharris(fftsize)
> > fft = gr.fft_vcc(fftsize, True, mywin)
> >
> > signal = usrp.source_c(0,udecim) # signal from Basic RX,
> > decimation=256
> > v_sink = gr.vector_sink_c()
> >
> > self.connect(signal, fft, v_sink)
> >
> > # Do stuff with v_sink.data()
> > print v_sink.data()
> >
> if __name__ == "__main__":
> > print "Initilizing.."
> > tb = topBlock()
> > print "Flowgraph start.."
> > tb.start()
> > print "Exiting.."
>
>
> but i get the same error:
>
> ValueError: itemsize mismatch: usrp1_source_c(2):0 using 8,
> fft_vcc_fftw(1):0 using 2048
>
>
> the value 2048 depends of the fft size 2048=8*256
>
> thank you very much!
You need to insert a gr.stream_to_vector block between the usrp and
the fft. Also, using vector_sink_c is not recommended for anything
but QA code that runs with a small number of samples. If used like
you are trying to use it, it will consume all of the memory on your
system. Use a gr.file_sink instead.
Eric