Re: [Discuss-gnuradio] usrp_spectrum_sense.py FFT bin values are all zero.

[Jincheng Zhang]

I want to use usrp_spectrum_sense.py to sweep the Hong Kong TV band which ranges from 470MHz to 806MHz and get every channel's power in dB. Each channel's frequency band is 8MHz. 

Now I'm using USRP2 with TVRX2 daughter board. I have installed the latest gnuraio and uhd. But when I use the usrp_spectrum_sense.py to get the power of each channel, some FFT bin values are extremely big. In particular, I'm not sure abou the self.connect(self.u, s2v, fft, c2mag, stats). It doesn't take "log" as the parameter, 

FFT size is 2048, sample-rate is 12.5MHz(to let the decimation be 8M), freq_step is 8MHz. Anyone has any ideas about how to use usrp_spectrum_sense.py to calculate each channel's power?

On Sun, Apr 7, 2013 at 8:24 PM, Jincheng Zhang <address@hidden> wrote:

Hi, all,

   I use the usrp_spectrum_sense.py to sweep the TV band from 470MHz to 806MHz. But when I use self.connect(self.u, s2v, fft, c2mag, log, stats), the FFT bin values I got are all zero. 

  Also, what's the magnitude of FFT bin value? Thanks. 

--

Best regards,

Jincheng Zhang

--

Best regards,

Jincheng Zhang
Department of Information Engineering

The Chinese University of Hong Kong

http://personal.ie.cuhk.edu.hk/~zj012/