Ivan, When the AD9361 is retuned, recalibration of various RF circuits may (need to) reoccur. The device driver looks how far you have retuned from a previous frequency, and if it exceeds a certain distance rerun’s this calibration, which takes time. Since Analog devices envisaged that this chip might need to be used in applications where fast hopping is required, it does have the ability to store multiple calibration settings locally in the radio and switch between them quickly, but this is not functionality that is used in basic operation under UHD. We may well have put API hook’s in there so you can manually call this functionality under UHD, but I can’t recall. Take a look at ADI’s documentation for more info.
-Ian > On Mar 11, 2019, at 7:49 AM, Ivan Zahartchuk via USRP-users > <usrp-users@lists.ettus.com> wrote: > > Hello. I have a problem with the usrp b200 board. I need a fast frequency > tuning for spectrum analysis. But when I increase the band over 200 MHz, that > is, more than 8 frequency adjustments, I have problems with time. It > increases dramatically. > Here is the code section where I measure the execution time of the frequency > setting function: > for i, freqq in enumerate (freq): > > recv_samps = 0 > self.usrp.set_rx_rate (bandwich [i]) > start = time.time () > self.usrp.set_rx_freq (lib.types.tune_request (freqq)) > > print (time.time () - start) > And I get the following results: > 0.154153108597 > 0.00300002098083 > 0.0029628276825 > 0.00299215316772 > 0.00298380851746 > 0.153974056244 > 0.153841018677 > 0.00304222106934 > 0.00305104255676 > 0.0030951499939 > 0.0030038356781 > 0.153944015503 > 0.153861045837 > 0.00292587280273 > 0.00306510925293 > 0.00301003456116 > 0.0029399394989 > With USRP N 210 there is no such problem. Tell me why this problem occurs and > how can it be solved? > Thanks in advance. Ivan > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com _______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
