On Mon, Sep 05, 2011 at 10:19:54AM -0400, John Ackermann N8UR wrote: > > I would think that you'd specify a bandpass filter around zero with a > low cutoff of, say, -40e3 and a high cutoff of +40e3. However, this > doesn't work -- the bandpass filter seems to require a number >0 for > the lowpass frequency.
That would be a low-pass filter with a cutoff at 40e3. With complex-valued signals, a low-pass filter is essentially a band-pass filter centered around 0 Hz. > there is a signal component on the output directly at the USRP center > frequency. It's at most about 30dB below the desired signals. I > assume this is the equivalent of LO leakage. Is there any way to > filter this out or at least reduce its amplitude? > > As I'm writing this, I wonder if the solution to both problems is to > put both my signals on one side of the USRP center frequency, say +25 > and +75 kHz. Yes, you could use an external analog band-pass filter if that center spur is a problem for you. _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
