Hi Cristian, agreeing with the other Marcus :) Also, 100 Mb/s might sound like much – but it's in fact relatively little. Each sample coming from your USRP has 16 bit real and 16 bit imaginary part, so that's a 32 bit per sample, or 320 Mb/s for a simple 10 MS/s stream.
Try with a USB2.0 port (not blue) and a rate of 8 MS/s. That should work without any "O". Since you don't seem to run into CPU shortage, I recommend trying a different USB3 controller. Some simply don't work well with the high, continued rate transfers that SDR devices need. Best regards, Marcus On 01.05.2017 01:39, Marcus D. Leech wrote: > On 04/30/2017 07:32 PM, Cristian Rodríguez wrote: >> Hi all, >> >> I'm doing a simple flowgraph so i can check if i am able to get >> enough samples to work with gr-ieee_802.11. >> >> It is the flowgraph i set. >> >> >> Imágenes integradas 1 >> >> >> Sample rate=50MHz → Several 0s, i think, a 0 each 5 seconds. >> >> Sample rate=20MHz → a few of 0s, i think, a 0 each 30 seconds. >> >> Sample rate=10MHz → a few of 0s, i think, a 0 each 60 seconds. >> >> For 10MHz was strange the fact, that Gnuradio seems ask for 40MHz in >> the clock rate. >> >> Imágenes integradas 2 >> >> The cpu usage was around 5%, and 60Mb-200Mb ram, the name of the >> process Python2. >> >> I checked the USB 3.0 speed by copying a file. The speed was around >> 100Mb/s >> >> I have the USRP B210 over USB 3.0. My pc is an I7 4710HQ (up to 3.5 >> Ghz 8 threads), 12 Gb RAM. >> >> It is supposed i can get until 62 Msamples/s, then i don't know what >> it is going wrong. >> >> What do you think i should set so i can get 20Mhz of sample rate >> without "0"s in the console? >> >> Thanks in advance. >> >> Best Regards, >> >> Cristian >> >> >> > Try setting > > num_recv_frames=128 > > In the device arguments, and see if this helps. > > Also, the B210 has a flexible master clock--the UHD drivers will pick > a master clock rate that provides good filtering performance for your > chosen > sample rate, at 10Msps, a 40MHz master clock is an appropriate > choice made by the driver. > > Also, keep in mind that even when you aren't "doing anything" with the > samples (as in your Gnu Radio example), a *tremendous* amount of > "stuff" has to happen to those samples on the way up from the > hardware in to your application. > > > > > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
_______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
