YES. I also found this fact that the dynamic ranges of two usrps are so different, just in these days.
Furthermore, the range of usrp.source_32fc is also +-1.0, right? Because I found the sample amplitude is very small when I use usrp2_fft.py observe the same RF input on USRP2, compared with usrp_fft.py on USRP. Lin 2009/8/11, Johnathan Corgan <[email protected]>: > > On Tue, 2009-08-11 at 09:38 -0600, Jordan J Riggs wrote: > > > Here is the FFT output of the two devices. > > This looks like gain compression or even clipping on the USRP2. > > The dynamic range of samples to be sent to the usrp.sink_c block for the > USRP1 is +- 32767. > > The dynamic range of samples to be sent to the usrp2.sink_32fc block for > the USRP2 is +-1.0. > > In either case, the RFX boards go into gain compression in the upper 20 > dB or so of their transmit range, so if you have a modulation which > requires linear frequency response (e.g., filtered BPSK), you need to > restrict the sample amplitude to +- 3000 or so for USRP1 and += 0.1 or > so for USRP2. > > If you are in fact sending the same actual sample range valid for the > USRP1 (+-32767) into the USRP2 sink, you will of course get severe > distortion as the sink will clip this to a +-1.0 square wave. > > Johnathan > > > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >
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