On Oct 18, 2011, at 11:18 AM, "Marcus D. Leech" <mle...@ripnet.com> wrote:
>> >> hi Marcus, >> >> I am attaching the screen shots and also block diagram of transmitter.. >> right now i am just trying to look for transmission of OFDM signal via >> usrp1. As i mentioned earlier in the fft scope plot in gnu radio i see the >> typical ofdm signal but on the other hand in usrp sink on the spectrum >> analyser i saw only simple sine wave peak. please have a look and let me >> know if there is something else do i need to do to generate the proper ofdm >> signal on the spectrum analyser. >> >> /home/hp/Desktop/spectrumoutput.jpeg >> http://old.nabble.com/file/p32675018/spectrumoutput.jpeg spectrumoutput.jpeg >> >> >> >> Block diagram in GNU radio >> /home/hp/Documents/finaltesting.grc >> http://old.nabble.com/file/p32675018/finaltesting.grc finaltesting.grc >> > Your flow-graph appears to be badly confused about bandwidths and > interpolations and sample rates > --an interpolation ratio on your USRP1 sink of 100e6 is almost > certainly *not* what you had in mind. > > You probably need to learn more about all of that, and get some better > notions of how the OFDM > modulator block works. At the very least you'll need to > fractionally-interpolate the baseband > up to some sample rather that *can* reasonably be further interpolated > by the USRP1 hardware. > > Given how simple this graph currently is, I'd *strongly* suggest that > you upgrade your "world" to UHD, > since your investment in the "old world" is still rather small. > > >> >> > -- > Principal Investigator > Shirleys Bay Radio Astronomy Consortium As of last night, the 'next' branch of GNU Radio (if you are using git) has the OFDM code and examples rewritten using UHD. Tom _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
