schrieb grc007 am 2010-06-17 23:28:
Hello, I need again your help for this problem: - I want to locate the peaks (local maximum) of the input signal, which is sinc-function pulse (the 2 gray points in picture sincpuls.png, not the neighbour peaks). How can I use the gr_peak_detector in grc to do this ?
If you know the exact shape of the signal you want to detect, you may get better results with doing a correlation with the desired signal first. Then you can use a threshold or a more sophisticated peak detector.
- If you look at my grc-picture (peakfalse.png) you will see that the peaks are not at the right places. They happen before the true peaks of the sine-function.
You did not show the complete flow graph in your pictures, but chances are good that its not early, but late.
Both the FFT sink and the peak detector need some time for processing reulting in some delay so you must not expect their output to be synced. You need to find out somehow both delays, or at least the difference of the delay. Try you flowgraph with other imput signals, like ramp.
Patrick -- Engineers motto: cheap, good, fast: choose any two Patrick Strasser <patrick dot strasser at tugraz dot at> Student of Telemati_cs_, Techn. University Graz, Austria _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
