On Mon, Jan 19, 2009 at 09:02:18AM -0200, Ronaldo Nunez wrote: > Hello GnuRadio community, > > I made a transmission path diagram to try to understand how USRP works. > I'm not sure if it's right, if somebody can correct it, it will be great! :D > > To debug the diagram I used these parameters, but I didn't get the > right output (using USRP v1 and BasicTX d'board). > > ## Defined by user## > f_signal = 4 MHz > usb_rate (signal sample rate) = 2 * f_signal = 8 MHz > L1 = 4 > f_LO = 5 MHz > > ## Defined by Software (automatic) ## > inter_sample_rate = usb_rate * L1 = 32MS/s > f1=? > f3=? > > ## Obtained inside AD9862 > f2=? > f4=? > > expected f4 = f_LO +/- f_signal = 5 MHz + 4 MHz = 9 MHz > = 5 MHz - 4 MHz = 1 MHz > ##Diagram## > http://img164.imageshack.us/img164/4476/diageralfinalenusjm4.png >
Ronaldo, These (and your previous questions) are all good. Have you tried printing out the result from: r = u.tune(...) print "r.baseband_freq", r.baseband_freq print "r.dxc_freq", r.dxc_freq print "r.residual_freq", r.residual_freq print "r.inverted", r.inverted The USB rate in complex samples/s is 128e6 / interp_rate Eric _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
