Re: [Discuss-gnuradio] Output of usrp_rx_cfile and Input of ATSC demodulator

[John Clark]

Wuest Brandon-WTVR47 schrieb:
> All,
>  
> In the hopes of trying to understand the various aspects of GNU Radio 
> and the USRP hardware, I am trying to use the ATSC demodulator 
> included with GNU Radio to create an MPEG transport stream from the 
> output of usrp_rx_cfile.py.  Something I know has been discussed many 
> times on this forum.
>  
> I am having a problems with disk writing not being able to keep up 
> with the high data rate, so I am trying to do a little manipulation of 
> the IQ data to get around this.  What I am trying to do it get 8-bit 
> samples from the usrp (which my disk can keep up with) and then before 
> I feed that in to interp.py, I convert every pair of bytes to 
> a complex<float>.

Perhaps I missed something here... if you are having problems recording 
2 '8-bit' integers, why would converting those integers to floats, that 
is creating now 2 4 byte quantities... improve performance in any way.

Back when I worried about such things, I usually thought about 
maintaining everything in 'integer' form, and should I have needed a 
'FFT', I would start thinking
about Galois Fields, prime generator polynomials... and the like, but 
stay with integers...

John Clark.