Hello Experts, I am trying to calibrate X310/UBX on the whole wifi bands (the complete 2.4 GHz band). 2.412,2.417,2.422,....,2.484 GHz I am doing direction finding tests and need to calibrate 4 channels of 2 X310s on the specified frequencies. Both X310s are connected with Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 GHz. For other bands, calibration does not remain after retuning. Is there any specific reason why the calibration only works for every 50 Mhz channel after retuning. I tested with different sampling rates, but the result is the same. Calibration does not remain after retuning. I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. Is there any specific way how I can make it work? Best regards Sanjoy Basak <https://mailtrack.io/> Sent with Mailtrack <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22>

Hello Sanjoy, What calibration are you referring to? Frequency, amplitude, phase? How are you doing your calibration and how are you checking it? The more you can tell us about your method and the results you are seeing the better we can answer. Regards, Derek On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < usrp-users@lists.ettus.com> wrote: > > Hello Experts, > I am trying to calibrate X310/UBX on the whole wifi bands (the complete > 2.4 GHz band). > 2.412,2.417,2.422,....,2.484 GHz > > I am doing direction finding tests and need to calibrate 4 channels of 2 > X310s on the specified frequencies. Both X310s are connected with > Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 > GHz. For other bands, calibration does not remain after retuning. Is there > any specific reason why the calibration only works for every 50 Mhz channel > after retuning. I tested with different sampling rates, but the result is > the same. Calibration does not remain after retuning. > > I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. Is > there any specific way how I can make it work? > > Best regards > Sanjoy Basak > > > > <https://mailtrack.io/> Sent with Mailtrack > <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > >

Hi Derek, I am referreing to phase calibration. I am taking one transmit signal (sine/cosine wave) from one x310 and distributing the signal through a 1x4 power divider and feeding it to 4 receivers of 2 other X310s. All the X310s are connected to the octoclock. Afterwards I am comparing the phase of 4 RX signals. For calibration, I take one rx signal as the reference signal and find the phase differences of other 3 rx signals compared to the reference signal. I save the offset (initial) phases and use it further for calibration. As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the phase calibration remains even after restarting (or retuning) the USRP. However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the phase calibration does not remain. After retuning, I find the calibration is gone. I also used set_command_time method. But the result was the same. Best regards Sanjoy <https://mailtrack.io/> Sent with Mailtrack <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> Sanjoy Basak Researcher Royal Military Academy Dept. Communication, Information Systems & Sensors (CISS) 30, Avenue de la Renaissance B-1000 Brussels BELGIUM Tel : +32-2441 4162 email: Sanjoy.BASAK@mil.be On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > Hello Sanjoy, > > What calibration are you referring to? Frequency, amplitude, phase? How > are you doing your calibration and how are you checking it? The more you > can tell us about your method and the results you are seeing the better we > can answer. > > Regards, > Derek > > On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < > usrp-users@lists.ettus.com> wrote: > >> >> Hello Experts, >> I am trying to calibrate X310/UBX on the whole wifi bands (the complete >> 2.4 GHz band). >> 2.412,2.417,2.422,....,2.484 GHz >> >> I am doing direction finding tests and need to calibrate 4 channels of 2 >> X310s on the specified frequencies. Both X310s are connected with >> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >> GHz. For other bands, calibration does not remain after retuning. Is there >> any specific reason why the calibration only works for every 50 Mhz channel >> after retuning. I tested with different sampling rates, but the result is >> the same. Calibration does not remain after retuning. >> >> I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. Is >> there any specific way how I can make it work? >> >> Best regards >> Sanjoy Basak >> >> >> >> <https://mailtrack.io/> Sent with Mailtrack >> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >> >> _______________________________________________ >> USRP-users mailing list >> USRP-users@lists.ettus.com >> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >> >> >

Hi Sanjoy, Timed commands will definitely be required in order to have repeatable phase offsets. To check, you are (re)setting the time on each X310 at the start of your program and have set the clock and time sources to external? Are you using the multi_usrp API and creating a single rx_streamer with all four channels? If you are using the RFNoC API then timed commands must be used to set the DDC frequency (if non-zero) as well since that has an effect on the phase which is stateful. Can you please paste your code for setting the rx frequency? Also for setting the motherboard time? Thank you, Derek On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com> wrote: > Hi Derek, > I am referreing to phase calibration. I am taking one transmit signal > (sine/cosine wave) from one x310 and distributing the signal through a 1x4 > power divider and feeding it to 4 receivers of 2 other X310s. All the X310s > are connected to the octoclock. Afterwards I am comparing the phase of 4 RX > signals. > > For calibration, I take one rx signal as the reference signal and find the > phase differences of other 3 rx signals compared to the reference signal. I > save the offset (initial) phases and use it further for calibration. > > As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the > phase calibration remains even after restarting (or retuning) the USRP. > However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the > phase calibration does not remain. After retuning, I find the calibration > is gone. > > I also used set_command_time method. But the result was the same. > > Best regards > Sanjoy > > > > <https://mailtrack.io/> Sent with Mailtrack > <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> > > Sanjoy Basak > Researcher > Royal Military Academy > Dept. Communication, Information Systems & Sensors (CISS) > 30, Avenue de la Renaissance > B-1000 Brussels > BELGIUM > Tel : +32-2441 4162 > email: Sanjoy.BASAK@mil.be > > On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > >> Hello Sanjoy, >> >> What calibration are you referring to? Frequency, amplitude, phase? How >> are you doing your calibration and how are you checking it? The more you >> can tell us about your method and the results you are seeing the better we >> can answer. >> >> Regards, >> Derek >> >> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >> usrp-users@lists.ettus.com> wrote: >> >>> >>> Hello Experts, >>> I am trying to calibrate X310/UBX on the whole wifi bands (the complete >>> 2.4 GHz band). >>> 2.412,2.417,2.422,....,2.484 GHz >>> >>> I am doing direction finding tests and need to calibrate 4 channels of 2 >>> X310s on the specified frequencies. Both X310s are connected with >>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >>> GHz. For other bands, calibration does not remain after retuning. Is there >>> any specific reason why the calibration only works for every 50 Mhz channel >>> after retuning. I tested with different sampling rates, but the result is >>> the same. Calibration does not remain after retuning. >>> >>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. >>> Is there any specific way how I can make it work? >>> >>> Best regards >>> Sanjoy Basak >>> >>> >>> >>> <https://mailtrack.io/> Sent with Mailtrack >>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>> >>> _______________________________________________ >>> USRP-users mailing list >>> USRP-users@lists.ettus.com >>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>> >>> >> >

Hi Derek, I am not using Rfnoc. The time and clock sources are set to external and motherboard time is also set correctly. Please have a look in the code. Right now I am using simple flowgraph and python codes to check the calibration. Please have a look. I am not getting the repeated offset phase. It is changing with every tuning. Best regards Sanjoy <https://mailtrack.io/> Sent with Mailtrack <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> Sanjoy Basak Researcher Royal Military Academy Dept. Communication, Information Systems & Sensors (CISS) 30, Avenue de la Renaissance B-1000 Brussels BELGIUM Tel : +32-2441 4162 email: Sanjoy.BASAK@mil.be On Mon, Jul 3, 2017 at 7:53 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > Hi Sanjoy, > > Timed commands will definitely be required in order to have repeatable > phase offsets. To check, you are (re)setting the time on each X310 at the > start of your program and have set the clock and time sources to external? > > Are you using the multi_usrp API and creating a single rx_streamer with > all four channels? If you are using the RFNoC API then timed commands must > be used to set the DDC frequency (if non-zero) as well since that has an > effect on the phase which is stateful. > > Can you please paste your code for setting the rx frequency? Also for > setting the motherboard time? > > Thank you, > Derek > > On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com> > wrote: > >> Hi Derek, >> I am referreing to phase calibration. I am taking one transmit signal >> (sine/cosine wave) from one x310 and distributing the signal through a 1x4 >> power divider and feeding it to 4 receivers of 2 other X310s. All the X310s >> are connected to the octoclock. Afterwards I am comparing the phase of 4 RX >> signals. >> >> For calibration, I take one rx signal as the reference signal and find >> the phase differences of other 3 rx signals compared to the reference >> signal. I save the offset (initial) phases and use it further for >> calibration. >> >> As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the >> phase calibration remains even after restarting (or retuning) the USRP. >> However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the >> phase calibration does not remain. After retuning, I find the calibration >> is gone. >> >> I also used set_command_time method. But the result was the same. >> >> Best regards >> Sanjoy >> >> >> >> <https://mailtrack.io/> Sent with Mailtrack >> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >> >> Sanjoy Basak >> Researcher >> Royal Military Academy >> Dept. Communication, Information Systems & Sensors (CISS) >> 30, Avenue de la Renaissance >> B-1000 Brussels >> BELGIUM >> Tel : +32-2441 4162 >> email: Sanjoy.BASAK@mil.be >> >> On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> >> wrote: >> >>> Hello Sanjoy, >>> >>> What calibration are you referring to? Frequency, amplitude, phase? How >>> are you doing your calibration and how are you checking it? The more you >>> can tell us about your method and the results you are seeing the better we >>> can answer. >>> >>> Regards, >>> Derek >>> >>> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >>> usrp-users@lists.ettus.com> wrote: >>> >>>> >>>> Hello Experts, >>>> I am trying to calibrate X310/UBX on the whole wifi bands (the complete >>>> 2.4 GHz band). >>>> 2.412,2.417,2.422,....,2.484 GHz >>>> >>>> I am doing direction finding tests and need to calibrate 4 channels of >>>> 2 X310s on the specified frequencies. Both X310s are connected with >>>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >>>> GHz. For other bands, calibration does not remain after retuning. Is there >>>> any specific reason why the calibration only works for every 50 Mhz channel >>>> after retuning. I tested with different sampling rates, but the result is >>>> the same. Calibration does not remain after retuning. >>>> >>>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. >>>> Is there any specific way how I can make it work? >>>> >>>> Best regards >>>> Sanjoy Basak >>>> >>>> >>>> >>>> <https://mailtrack.io/> Sent with Mailtrack >>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>> >>>> _______________________________________________ >>>> USRP-users mailing list >>>> USRP-users@lists.ettus.com >>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>>> >>>> >>> >> >

Hello Sanjoy, Your initial calls to set_center_freq are all correct and use the command time. However the other call to set_center_freq must also the set_command_time call. Regards, Derek On Tue, Jul 4, 2017 at 10:09 AM, Sanjoy Basak <sanjoybasak14@gmail.com> wrote: > Hi Derek, > I am not using Rfnoc. The time and clock sources are set to external and > motherboard time is also set correctly. Please have a look in the code. > > Right now I am using simple flowgraph and python codes to check the > calibration. Please have a look. I am not getting the repeated offset > phase. It is changing with every tuning. > > Best regards > Sanjoy > > > > <https://mailtrack.io/> Sent with Mailtrack > <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> > > Sanjoy Basak > Researcher > Royal Military Academy > Dept. Communication, Information Systems & Sensors (CISS) > 30, Avenue de la Renaissance > B-1000 Brussels > BELGIUM > Tel : +32-2441 4162 > email: Sanjoy.BASAK@mil.be > > On Mon, Jul 3, 2017 at 7:53 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > >> Hi Sanjoy, >> >> Timed commands will definitely be required in order to have repeatable >> phase offsets. To check, you are (re)setting the time on each X310 at the >> start of your program and have set the clock and time sources to external? >> >> Are you using the multi_usrp API and creating a single rx_streamer with >> all four channels? If you are using the RFNoC API then timed commands must >> be used to set the DDC frequency (if non-zero) as well since that has an >> effect on the phase which is stateful. >> >> Can you please paste your code for setting the rx frequency? Also for >> setting the motherboard time? >> >> Thank you, >> Derek >> >> On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com> >> wrote: >> >>> Hi Derek, >>> I am referreing to phase calibration. I am taking one transmit signal >>> (sine/cosine wave) from one x310 and distributing the signal through a 1x4 >>> power divider and feeding it to 4 receivers of 2 other X310s. All the X310s >>> are connected to the octoclock. Afterwards I am comparing the phase of 4 RX >>> signals. >>> >>> For calibration, I take one rx signal as the reference signal and find >>> the phase differences of other 3 rx signals compared to the reference >>> signal. I save the offset (initial) phases and use it further for >>> calibration. >>> >>> As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the >>> phase calibration remains even after restarting (or retuning) the USRP. >>> However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the >>> phase calibration does not remain. After retuning, I find the calibration >>> is gone. >>> >>> I also used set_command_time method. But the result was the same. >>> >>> Best regards >>> Sanjoy >>> >>> >>> >>> <https://mailtrack.io/> Sent with Mailtrack >>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>> >>> Sanjoy Basak >>> Researcher >>> Royal Military Academy >>> Dept. Communication, Information Systems & Sensors (CISS) >>> 30, Avenue de la Renaissance >>> B-1000 Brussels >>> BELGIUM >>> Tel : +32-2441 4162 >>> email: Sanjoy.BASAK@mil.be >>> >>> On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> >>> wrote: >>> >>>> Hello Sanjoy, >>>> >>>> What calibration are you referring to? Frequency, amplitude, phase? How >>>> are you doing your calibration and how are you checking it? The more you >>>> can tell us about your method and the results you are seeing the better we >>>> can answer. >>>> >>>> Regards, >>>> Derek >>>> >>>> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >>>> usrp-users@lists.ettus.com> wrote: >>>> >>>>> >>>>> Hello Experts, >>>>> I am trying to calibrate X310/UBX on the whole wifi bands (the >>>>> complete 2.4 GHz band). >>>>> 2.412,2.417,2.422,....,2.484 GHz >>>>> >>>>> I am doing direction finding tests and need to calibrate 4 channels of >>>>> 2 X310s on the specified frequencies. Both X310s are connected with >>>>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >>>>> GHz. For other bands, calibration does not remain after retuning. Is there >>>>> any specific reason why the calibration only works for every 50 Mhz channel >>>>> after retuning. I tested with different sampling rates, but the result is >>>>> the same. Calibration does not remain after retuning. >>>>> >>>>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu 16.04. >>>>> Is there any specific way how I can make it work? >>>>> >>>>> Best regards >>>>> Sanjoy Basak >>>>> >>>>> >>>>> >>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>> >>>>> _______________________________________________ >>>>> USRP-users mailing list >>>>> USRP-users@lists.ettus.com >>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>>>> >>>>> >>>> >>> >> >

Hi Derek, I am using transmitter on continuous mode and then testing the phase of the receivers with that python file. So, I am not retuning the transmitter again. It's tuned once and then I am retuning the receiver and testing if the phase is the same or different. So, with different retune the receivers are having different offset phases at these frequencies. I also tested with transmitter and receiver together, transmitting and receiving at the same time and also tuning at the same time (with the attached python file). However, I am getting the same result. The offset phases is different at different retunes. Best regards Sanjoy <https://mailtrack.io/> Sent with Mailtrack <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> Sanjoy Basak Researcher Royal Military Academy Dept. Communication, Information Systems & Sensors (CISS) 30, Avenue de la Renaissance B-1000 Brussels BELGIUM Tel : +32-2441 4162 email: Sanjoy.BASAK@mil.be On Tue, Jul 4, 2017 at 12:00 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > Hello Sanjoy, > > Your initial calls to set_center_freq are all correct and use the command > time. However the other call to set_center_freq must also the > set_command_time call. > > Regards, > Derek > > On Tue, Jul 4, 2017 at 10:09 AM, Sanjoy Basak <sanjoybasak14@gmail.com> > wrote: > >> Hi Derek, >> I am not using Rfnoc. The time and clock sources are set to external and >> motherboard time is also set correctly. Please have a look in the code. >> >> Right now I am using simple flowgraph and python codes to check the >> calibration. Please have a look. I am not getting the repeated offset >> phase. It is changing with every tuning. >> >> Best regards >> Sanjoy >> >> >> >> <https://mailtrack.io/> Sent with Mailtrack >> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >> >> Sanjoy Basak >> Researcher >> Royal Military Academy >> Dept. Communication, Information Systems & Sensors (CISS) >> 30, Avenue de la Renaissance >> B-1000 Brussels >> BELGIUM >> Tel : +32-2441 4162 >> email: Sanjoy.BASAK@mil.be >> >> On Mon, Jul 3, 2017 at 7:53 PM, Derek Kozel <derek.kozel@ettus.com> >> wrote: >> >>> Hi Sanjoy, >>> >>> Timed commands will definitely be required in order to have repeatable >>> phase offsets. To check, you are (re)setting the time on each X310 at the >>> start of your program and have set the clock and time sources to external? >>> >>> Are you using the multi_usrp API and creating a single rx_streamer with >>> all four channels? If you are using the RFNoC API then timed commands must >>> be used to set the DDC frequency (if non-zero) as well since that has an >>> effect on the phase which is stateful. >>> >>> Can you please paste your code for setting the rx frequency? Also for >>> setting the motherboard time? >>> >>> Thank you, >>> Derek >>> >>> On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com> >>> wrote: >>> >>>> Hi Derek, >>>> I am referreing to phase calibration. I am taking one transmit signal >>>> (sine/cosine wave) from one x310 and distributing the signal through a 1x4 >>>> power divider and feeding it to 4 receivers of 2 other X310s. All the X310s >>>> are connected to the octoclock. Afterwards I am comparing the phase of 4 RX >>>> signals. >>>> >>>> For calibration, I take one rx signal as the reference signal and find >>>> the phase differences of other 3 rx signals compared to the reference >>>> signal. I save the offset (initial) phases and use it further for >>>> calibration. >>>> >>>> As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the >>>> phase calibration remains even after restarting (or retuning) the USRP. >>>> However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the >>>> phase calibration does not remain. After retuning, I find the calibration >>>> is gone. >>>> >>>> I also used set_command_time method. But the result was the same. >>>> >>>> Best regards >>>> Sanjoy >>>> >>>> >>>> >>>> <https://mailtrack.io/> Sent with Mailtrack >>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>> >>>> Sanjoy Basak >>>> Researcher >>>> Royal Military Academy >>>> Dept. Communication, Information Systems & Sensors (CISS) >>>> 30, Avenue de la Renaissance >>>> B-1000 Brussels >>>> BELGIUM >>>> Tel : +32-2441 4162 >>>> email: Sanjoy.BASAK@mil.be >>>> >>>> On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> >>>> wrote: >>>> >>>>> Hello Sanjoy, >>>>> >>>>> What calibration are you referring to? Frequency, amplitude, phase? >>>>> How are you doing your calibration and how are you checking it? The more >>>>> you can tell us about your method and the results you are seeing the better >>>>> we can answer. >>>>> >>>>> Regards, >>>>> Derek >>>>> >>>>> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >>>>> usrp-users@lists.ettus.com> wrote: >>>>> >>>>>> >>>>>> Hello Experts, >>>>>> I am trying to calibrate X310/UBX on the whole wifi bands (the >>>>>> complete 2.4 GHz band). >>>>>> 2.412,2.417,2.422,....,2.484 GHz >>>>>> >>>>>> I am doing direction finding tests and need to calibrate 4 channels >>>>>> of 2 X310s on the specified frequencies. Both X310s are connected with >>>>>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >>>>>> GHz. For other bands, calibration does not remain after retuning. Is there >>>>>> any specific reason why the calibration only works for every 50 Mhz channel >>>>>> after retuning. I tested with different sampling rates, but the result is >>>>>> the same. Calibration does not remain after retuning. >>>>>> >>>>>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu >>>>>> 16.04. Is there any specific way how I can make it work? >>>>>> >>>>>> Best regards >>>>>> Sanjoy Basak >>>>>> >>>>>> >>>>>> >>>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>>> >>>>>> _______________________________________________ >>>>>> USRP-users mailing list >>>>>> USRP-users@lists.ettus.com >>>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>>>>> >>>>>> >>>>> >>>> >>> >> >

def set_f(self, f):
    self.f = f
    self.transmitter.set_center_freq(self.f, 0)
    self.transmitter.set_center_freq(self.f, 1)
    self.receiver.set_center_freq(self.f, 0)
    self.receiver.set_center_freq(self.f, 1)
    self.receiver.set_center_freq(self.f, 2)
    self.receiver.set_center_freq(self.f, 3)

The transmitter will not have a meaningful phase value. You are comparing the offsets between the four receivers. Looking at your cal_test4.py file we can see that the set_f function tunes the transmitter and receivers and does not use timed commands. This is also true for your receive only cal_test_try.py. You will need to add timed commands to those so that all four channels tune simultaneously. def set_f(self, f): self.f = f self.transmitter.set_center_freq(self.f, 0) self.transmitter.set_center_freq(self.f, 1) self.receiver.set_center_freq(self.f, 0) self.receiver.set_center_freq(self.f, 1) self.receiver.set_center_freq(self.f, 2) self.receiver.set_center_freq(self.f, 3) On Tue, Jul 4, 2017 at 1:51 PM, Sanjoy Basak <sanjoybasak14@gmail.com> wrote: > Hi Derek, > I am using transmitter on continuous mode and then testing the phase of > the receivers with that python file. So, I am not retuning the transmitter > again. It's tuned once and then I am retuning the receiver and testing if > the phase is the same or different. So, with different retune the receivers > are having different offset phases at these frequencies. > > I also tested with transmitter and receiver together, transmitting and > receiving at the same time and also tuning at the same time (with the > attached python file). However, I am getting the same result. The offset > phases is different at different retunes. > > Best regards > Sanjoy > > > > > > <https://mailtrack.io/> Sent with Mailtrack > <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> > > Sanjoy Basak > Researcher > Royal Military Academy > Dept. Communication, Information Systems & Sensors (CISS) > 30, Avenue de la Renaissance > B-1000 Brussels > BELGIUM > Tel : +32-2441 4162 > email: Sanjoy.BASAK@mil.be > > On Tue, Jul 4, 2017 at 12:00 PM, Derek Kozel <derek.kozel@ettus.com> > wrote: > >> Hello Sanjoy, >> >> Your initial calls to set_center_freq are all correct and use the command >> time. However the other call to set_center_freq must also the >> set_command_time call. >> >> Regards, >> Derek >> >> On Tue, Jul 4, 2017 at 10:09 AM, Sanjoy Basak <sanjoybasak14@gmail.com> >> wrote: >> >>> Hi Derek, >>> I am not using Rfnoc. The time and clock sources are set to external and >>> motherboard time is also set correctly. Please have a look in the code. >>> >>> Right now I am using simple flowgraph and python codes to check the >>> calibration. Please have a look. I am not getting the repeated offset >>> phase. It is changing with every tuning. >>> >>> Best regards >>> Sanjoy >>> >>> >>> >>> <https://mailtrack.io/> Sent with Mailtrack >>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>> >>> Sanjoy Basak >>> Researcher >>> Royal Military Academy >>> Dept. Communication, Information Systems & Sensors (CISS) >>> 30, Avenue de la Renaissance >>> B-1000 Brussels >>> BELGIUM >>> Tel : +32-2441 4162 >>> email: Sanjoy.BASAK@mil.be >>> >>> On Mon, Jul 3, 2017 at 7:53 PM, Derek Kozel <derek.kozel@ettus.com> >>> wrote: >>> >>>> Hi Sanjoy, >>>> >>>> Timed commands will definitely be required in order to have repeatable >>>> phase offsets. To check, you are (re)setting the time on each X310 at the >>>> start of your program and have set the clock and time sources to external? >>>> >>>> Are you using the multi_usrp API and creating a single rx_streamer with >>>> all four channels? If you are using the RFNoC API then timed commands must >>>> be used to set the DDC frequency (if non-zero) as well since that has an >>>> effect on the phase which is stateful. >>>> >>>> Can you please paste your code for setting the rx frequency? Also for >>>> setting the motherboard time? >>>> >>>> Thank you, >>>> Derek >>>> >>>> On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com> >>>> wrote: >>>> >>>>> Hi Derek, >>>>> I am referreing to phase calibration. I am taking one transmit signal >>>>> (sine/cosine wave) from one x310 and distributing the signal through a 1x4 >>>>> power divider and feeding it to 4 receivers of 2 other X310s. All the X310s >>>>> are connected to the octoclock. Afterwards I am comparing the phase of 4 RX >>>>> signals. >>>>> >>>>> For calibration, I take one rx signal as the reference signal and find >>>>> the phase differences of other 3 rx signals compared to the reference >>>>> signal. I save the offset (initial) phases and use it further for >>>>> calibration. >>>>> >>>>> As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the >>>>> phase calibration remains even after restarting (or retuning) the USRP. >>>>> However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the >>>>> phase calibration does not remain. After retuning, I find the calibration >>>>> is gone. >>>>> >>>>> I also used set_command_time method. But the result was the same. >>>>> >>>>> Best regards >>>>> Sanjoy >>>>> >>>>> >>>>> >>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>> >>>>> Sanjoy Basak >>>>> Researcher >>>>> Royal Military Academy >>>>> Dept. Communication, Information Systems & Sensors (CISS) >>>>> 30, Avenue de la Renaissance >>>>> B-1000 Brussels >>>>> BELGIUM >>>>> Tel : +32-2441 4162 >>>>> email: Sanjoy.BASAK@mil.be >>>>> >>>>> On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> >>>>> wrote: >>>>> >>>>>> Hello Sanjoy, >>>>>> >>>>>> What calibration are you referring to? Frequency, amplitude, phase? >>>>>> How are you doing your calibration and how are you checking it? The more >>>>>> you can tell us about your method and the results you are seeing the better >>>>>> we can answer. >>>>>> >>>>>> Regards, >>>>>> Derek >>>>>> >>>>>> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >>>>>> usrp-users@lists.ettus.com> wrote: >>>>>> >>>>>>> >>>>>>> Hello Experts, >>>>>>> I am trying to calibrate X310/UBX on the whole wifi bands (the >>>>>>> complete 2.4 GHz band). >>>>>>> 2.412,2.417,2.422,....,2.484 GHz >>>>>>> >>>>>>> I am doing direction finding tests and need to calibrate 4 channels >>>>>>> of 2 X310s on the specified frequencies. Both X310s are connected with >>>>>>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >>>>>>> GHz. For other bands, calibration does not remain after retuning. Is there >>>>>>> any specific reason why the calibration only works for every 50 Mhz channel >>>>>>> after retuning. I tested with different sampling rates, but the result is >>>>>>> the same. Calibration does not remain after retuning. >>>>>>> >>>>>>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu >>>>>>> 16.04. Is there any specific way how I can make it work? >>>>>>> >>>>>>> Best regards >>>>>>> Sanjoy Basak >>>>>>> >>>>>>> >>>>>>> >>>>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> USRP-users mailing list >>>>>>> USRP-users@lists.ettus.com >>>>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>>>>>> >>>>>>> >>>>>> >>>>> >>>> >>> >> >

    self.receiver.set_center_freq(freq, 0)
    self.receiver.set_center_freq(freq, 1)
    self.receiver.set_center_freq(freq, 2)
    self.receiver.set_center_freq(freq, 3)

    self.receiver.clear_command_time()

 def set_f(self, f):
     self.f = f
     self.transmitter.set_center_freq(self.f, 0)
     self.transmitter.set_center_freq(self.f, 1)
     self.receiver.set_center_freq(self.f, 0)
     self.receiver.set_center_freq(self.f, 1)
     self.receiver.set_center_freq(self.f, 2)
     self.receiver.set_center_freq(self.f, 3)

I used timed command once. now = self.receiver.get_time_now() cmd_time=now+uhd.time_spec(0.5) self.receiver.set_command_time(cmd_time) self.receiver.set_center_freq(freq, 0) self.receiver.set_center_freq(freq, 1) self.receiver.set_center_freq(freq, 2) self.receiver.set_center_freq(freq, 3) self.receiver.clear_command_time() Isn't this enough? How do I add timed command before set_f function (for receive only cal_test_try.py file)? <https://mailtrack.io/> Sent with Mailtrack <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> Sanjoy Basak Researcher Royal Military Academy Dept. Communication, Information Systems & Sensors (CISS) 30, Avenue de la Renaissance B-1000 Brussels BELGIUM Tel : +32-2441 4162 email: Sanjoy.BASAK@mil.be On Tue, Jul 4, 2017 at 3:52 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > The transmitter will not have a meaningful phase value. You are comparing > the offsets between the four receivers. Looking at your cal_test4.py file > we can see that the set_f function tunes the transmitter and receivers and > does not use timed commands. This is also true for your receive only > cal_test_try.py. You will need to add timed commands to those so that all > four channels tune simultaneously. > > def set_f(self, f): > self.f = f > self.transmitter.set_center_freq(self.f, 0) > self.transmitter.set_center_freq(self.f, 1) > self.receiver.set_center_freq(self.f, 0) > self.receiver.set_center_freq(self.f, 1) > self.receiver.set_center_freq(self.f, 2) > self.receiver.set_center_freq(self.f, 3) > > > On Tue, Jul 4, 2017 at 1:51 PM, Sanjoy Basak <sanjoybasak14@gmail.com> > wrote: > >> Hi Derek, >> I am using transmitter on continuous mode and then testing the phase of >> the receivers with that python file. So, I am not retuning the transmitter >> again. It's tuned once and then I am retuning the receiver and testing if >> the phase is the same or different. So, with different retune the receivers >> are having different offset phases at these frequencies. >> >> I also tested with transmitter and receiver together, transmitting and >> receiving at the same time and also tuning at the same time (with the >> attached python file). However, I am getting the same result. The offset >> phases is different at different retunes. >> >> Best regards >> Sanjoy >> >> >> >> >> >> <https://mailtrack.io/> Sent with Mailtrack >> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >> >> Sanjoy Basak >> Researcher >> Royal Military Academy >> Dept. Communication, Information Systems & Sensors (CISS) >> 30, Avenue de la Renaissance >> B-1000 Brussels >> BELGIUM >> Tel : +32-2441 4162 >> email: Sanjoy.BASAK@mil.be >> >> On Tue, Jul 4, 2017 at 12:00 PM, Derek Kozel <derek.kozel@ettus.com> >> wrote: >> >>> Hello Sanjoy, >>> >>> Your initial calls to set_center_freq are all correct and use the >>> command time. However the other call to set_center_freq must also the >>> set_command_time call. >>> >>> Regards, >>> Derek >>> >>> On Tue, Jul 4, 2017 at 10:09 AM, Sanjoy Basak <sanjoybasak14@gmail.com> >>> wrote: >>> >>>> Hi Derek, >>>> I am not using Rfnoc. The time and clock sources are set to external >>>> and motherboard time is also set correctly. Please have a look in the code. >>>> >>>> Right now I am using simple flowgraph and python codes to check the >>>> calibration. Please have a look. I am not getting the repeated offset >>>> phase. It is changing with every tuning. >>>> >>>> Best regards >>>> Sanjoy >>>> >>>> >>>> >>>> <https://mailtrack.io/> Sent with Mailtrack >>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>> >>>> Sanjoy Basak >>>> Researcher >>>> Royal Military Academy >>>> Dept. Communication, Information Systems & Sensors (CISS) >>>> 30, Avenue de la Renaissance >>>> B-1000 Brussels >>>> BELGIUM >>>> Tel : +32-2441 4162 >>>> email: Sanjoy.BASAK@mil.be >>>> >>>> On Mon, Jul 3, 2017 at 7:53 PM, Derek Kozel <derek.kozel@ettus.com> >>>> wrote: >>>> >>>>> Hi Sanjoy, >>>>> >>>>> Timed commands will definitely be required in order to have repeatable >>>>> phase offsets. To check, you are (re)setting the time on each X310 at the >>>>> start of your program and have set the clock and time sources to external? >>>>> >>>>> Are you using the multi_usrp API and creating a single rx_streamer >>>>> with all four channels? If you are using the RFNoC API then timed commands >>>>> must be used to set the DDC frequency (if non-zero) as well since that has >>>>> an effect on the phase which is stateful. >>>>> >>>>> Can you please paste your code for setting the rx frequency? Also for >>>>> setting the motherboard time? >>>>> >>>>> Thank you, >>>>> Derek >>>>> >>>>> On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com> >>>>> wrote: >>>>> >>>>>> Hi Derek, >>>>>> I am referreing to phase calibration. I am taking one transmit signal >>>>>> (sine/cosine wave) from one x310 and distributing the signal through a 1x4 >>>>>> power divider and feeding it to 4 receivers of 2 other X310s. All the X310s >>>>>> are connected to the octoclock. Afterwards I am comparing the phase of 4 RX >>>>>> signals. >>>>>> >>>>>> For calibration, I take one rx signal as the reference signal and >>>>>> find the phase differences of other 3 rx signals compared to the reference >>>>>> signal. I save the offset (initial) phases and use it further for >>>>>> calibration. >>>>>> >>>>>> As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find the >>>>>> phase calibration remains even after restarting (or retuning) the USRP. >>>>>> However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the >>>>>> phase calibration does not remain. After retuning, I find the calibration >>>>>> is gone. >>>>>> >>>>>> I also used set_command_time method. But the result was the same. >>>>>> >>>>>> Best regards >>>>>> Sanjoy >>>>>> >>>>>> >>>>>> >>>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>>> >>>>>> Sanjoy Basak >>>>>> Researcher >>>>>> Royal Military Academy >>>>>> Dept. Communication, Information Systems & Sensors (CISS) >>>>>> 30, Avenue de la Renaissance >>>>>> B-1000 Brussels >>>>>> BELGIUM >>>>>> Tel : +32-2441 4162 >>>>>> email: Sanjoy.BASAK@mil.be >>>>>> >>>>>> On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> >>>>>> wrote: >>>>>> >>>>>>> Hello Sanjoy, >>>>>>> >>>>>>> What calibration are you referring to? Frequency, amplitude, phase? >>>>>>> How are you doing your calibration and how are you checking it? The more >>>>>>> you can tell us about your method and the results you are seeing the better >>>>>>> we can answer. >>>>>>> >>>>>>> Regards, >>>>>>> Derek >>>>>>> >>>>>>> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >>>>>>> usrp-users@lists.ettus.com> wrote: >>>>>>> >>>>>>>> >>>>>>>> Hello Experts, >>>>>>>> I am trying to calibrate X310/UBX on the whole wifi bands (the >>>>>>>> complete 2.4 GHz band). >>>>>>>> 2.412,2.417,2.422,....,2.484 GHz >>>>>>>> >>>>>>>> I am doing direction finding tests and need to calibrate 4 channels >>>>>>>> of 2 X310s on the specified frequencies. Both X310s are connected with >>>>>>>> Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 GHz, 2.5 >>>>>>>> GHz. For other bands, calibration does not remain after retuning. Is there >>>>>>>> any specific reason why the calibration only works for every 50 Mhz channel >>>>>>>> after retuning. I tested with different sampling rates, but the result is >>>>>>>> the same. Calibration does not remain after retuning. >>>>>>>> >>>>>>>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu >>>>>>>> 16.04. Is there any specific way how I can make it work? >>>>>>>> >>>>>>>> Best regards >>>>>>>> Sanjoy Basak >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> USRP-users mailing list >>>>>>>> USRP-users@lists.ettus.com >>>>>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>> >>>> >>> >> >

     self.receiver.set_center_freq(freq, 0)
     self.receiver.set_center_freq(freq, 1)
     self.receiver.set_center_freq(freq, 2)
     self.receiver.set_center_freq(freq, 3)

     self.receiver.clear_command_time()

 def set_f(self, f):
     self.f = f
     self.transmitter.set_center_freq(self.f, 0)
     self.transmitter.set_center_freq(self.f, 1)
     self.receiver.set_center_freq(self.f, 0)
     self.receiver.set_center_freq(self.f, 1)
     self.receiver.set_center_freq(self.f, 2)
     self.receiver.set_center_freq(self.f, 3)

The code fragment in your last email is enough, but it is necessary that every call to set_center_freq is wrapped like that. You can edit the cal_test_try.py file to add the calls to the time functions. If there is ever a call to change the tune frequency it must be done timed or the results will not be consistent. On Tue, Jul 4, 2017 at 3:02 PM, Sanjoy Basak <sanjoybasak14@gmail.com> wrote: > I used timed command once. > > now = self.receiver.get_time_now() > cmd_time=now+uhd.time_spec(0.5) > > self.receiver.set_command_time(cmd_time) > > self.receiver.set_center_freq(freq, 0) > self.receiver.set_center_freq(freq, 1) > self.receiver.set_center_freq(freq, 2) > self.receiver.set_center_freq(freq, 3) > > self.receiver.clear_command_time() > > Isn't this enough? > > How do I add timed command before set_f function (for receive only > cal_test_try.py file)? > > > > <https://mailtrack.io/> Sent with Mailtrack > <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> > > Sanjoy Basak > Researcher > Royal Military Academy > Dept. Communication, Information Systems & Sensors (CISS) > 30, Avenue de la Renaissance > B-1000 Brussels > BELGIUM > Tel : +32-2441 4162 > email: Sanjoy.BASAK@mil.be > > On Tue, Jul 4, 2017 at 3:52 PM, Derek Kozel <derek.kozel@ettus.com> wrote: > >> The transmitter will not have a meaningful phase value. You are comparing >> the offsets between the four receivers. Looking at your cal_test4.py file >> we can see that the set_f function tunes the transmitter and receivers and >> does not use timed commands. This is also true for your receive only >> cal_test_try.py. You will need to add timed commands to those so that all >> four channels tune simultaneously. >> >> def set_f(self, f): >> self.f = f >> self.transmitter.set_center_freq(self.f, 0) >> self.transmitter.set_center_freq(self.f, 1) >> self.receiver.set_center_freq(self.f, 0) >> self.receiver.set_center_freq(self.f, 1) >> self.receiver.set_center_freq(self.f, 2) >> self.receiver.set_center_freq(self.f, 3) >> >> >> On Tue, Jul 4, 2017 at 1:51 PM, Sanjoy Basak <sanjoybasak14@gmail.com> >> wrote: >> >>> Hi Derek, >>> I am using transmitter on continuous mode and then testing the phase of >>> the receivers with that python file. So, I am not retuning the transmitter >>> again. It's tuned once and then I am retuning the receiver and testing if >>> the phase is the same or different. So, with different retune the receivers >>> are having different offset phases at these frequencies. >>> >>> I also tested with transmitter and receiver together, transmitting and >>> receiving at the same time and also tuning at the same time (with the >>> attached python file). However, I am getting the same result. The offset >>> phases is different at different retunes. >>> >>> Best regards >>> Sanjoy >>> >>> >>> >>> >>> >>> <https://mailtrack.io/> Sent with Mailtrack >>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>> >>> Sanjoy Basak >>> Researcher >>> Royal Military Academy >>> Dept. Communication, Information Systems & Sensors (CISS) >>> 30, Avenue de la Renaissance >>> B-1000 Brussels >>> BELGIUM >>> Tel : +32-2441 4162 >>> email: Sanjoy.BASAK@mil.be >>> >>> On Tue, Jul 4, 2017 at 12:00 PM, Derek Kozel <derek.kozel@ettus.com> >>> wrote: >>> >>>> Hello Sanjoy, >>>> >>>> Your initial calls to set_center_freq are all correct and use the >>>> command time. However the other call to set_center_freq must also the >>>> set_command_time call. >>>> >>>> Regards, >>>> Derek >>>> >>>> On Tue, Jul 4, 2017 at 10:09 AM, Sanjoy Basak <sanjoybasak14@gmail.com> >>>> wrote: >>>> >>>>> Hi Derek, >>>>> I am not using Rfnoc. The time and clock sources are set to external >>>>> and motherboard time is also set correctly. Please have a look in the code. >>>>> >>>>> Right now I am using simple flowgraph and python codes to check the >>>>> calibration. Please have a look. I am not getting the repeated offset >>>>> phase. It is changing with every tuning. >>>>> >>>>> Best regards >>>>> Sanjoy >>>>> >>>>> >>>>> >>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>> >>>>> Sanjoy Basak >>>>> Researcher >>>>> Royal Military Academy >>>>> Dept. Communication, Information Systems & Sensors (CISS) >>>>> 30, Avenue de la Renaissance >>>>> B-1000 Brussels >>>>> BELGIUM >>>>> Tel : +32-2441 4162 >>>>> email: Sanjoy.BASAK@mil.be >>>>> >>>>> On Mon, Jul 3, 2017 at 7:53 PM, Derek Kozel <derek.kozel@ettus.com> >>>>> wrote: >>>>> >>>>>> Hi Sanjoy, >>>>>> >>>>>> Timed commands will definitely be required in order to have >>>>>> repeatable phase offsets. To check, you are (re)setting the time on each >>>>>> X310 at the start of your program and have set the clock and time sources >>>>>> to external? >>>>>> >>>>>> Are you using the multi_usrp API and creating a single rx_streamer >>>>>> with all four channels? If you are using the RFNoC API then timed commands >>>>>> must be used to set the DDC frequency (if non-zero) as well since that has >>>>>> an effect on the phase which is stateful. >>>>>> >>>>>> Can you please paste your code for setting the rx frequency? Also for >>>>>> setting the motherboard time? >>>>>> >>>>>> Thank you, >>>>>> Derek >>>>>> >>>>>> On Mon, Jul 3, 2017 at 6:20 PM, Sanjoy Basak <sanjoybasak14@gmail.com >>>>>> > wrote: >>>>>> >>>>>>> Hi Derek, >>>>>>> I am referreing to phase calibration. I am taking one transmit >>>>>>> signal (sine/cosine wave) from one x310 and distributing the signal through >>>>>>> a 1x4 power divider and feeding it to 4 receivers of 2 other X310s. All the >>>>>>> X310s are connected to the octoclock. Afterwards I am comparing the phase >>>>>>> of 4 RX signals. >>>>>>> >>>>>>> For calibration, I take one rx signal as the reference signal and >>>>>>> find the phase differences of other 3 rx signals compared to the reference >>>>>>> signal. I save the offset (initial) phases and use it further for >>>>>>> calibration. >>>>>>> >>>>>>> As I mentioned earlier, for 2.4 GHz, 2.45 GHz and 2.5 Ghz, I find >>>>>>> the phase calibration remains even after restarting (or retuning) the USRP. >>>>>>> However, for other Wifi bands (for example 2412 MHz or 2452 MHz ...) the >>>>>>> phase calibration does not remain. After retuning, I find the calibration >>>>>>> is gone. >>>>>>> >>>>>>> I also used set_command_time method. But the result was the same. >>>>>>> >>>>>>> Best regards >>>>>>> Sanjoy >>>>>>> >>>>>>> >>>>>>> >>>>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>>>> >>>>>>> Sanjoy Basak >>>>>>> Researcher >>>>>>> Royal Military Academy >>>>>>> Dept. Communication, Information Systems & Sensors (CISS) >>>>>>> 30, Avenue de la Renaissance >>>>>>> B-1000 Brussels >>>>>>> BELGIUM >>>>>>> Tel : +32-2441 4162 >>>>>>> email: Sanjoy.BASAK@mil.be >>>>>>> >>>>>>> On Mon, Jul 3, 2017 at 6:29 PM, Derek Kozel <derek.kozel@ettus.com> >>>>>>> wrote: >>>>>>> >>>>>>>> Hello Sanjoy, >>>>>>>> >>>>>>>> What calibration are you referring to? Frequency, amplitude, phase? >>>>>>>> How are you doing your calibration and how are you checking it? The more >>>>>>>> you can tell us about your method and the results you are seeing the better >>>>>>>> we can answer. >>>>>>>> >>>>>>>> Regards, >>>>>>>> Derek >>>>>>>> >>>>>>>> On Mon, Jul 3, 2017 at 4:46 PM, Sanjoy Basak via USRP-users < >>>>>>>> usrp-users@lists.ettus.com> wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> Hello Experts, >>>>>>>>> I am trying to calibrate X310/UBX on the whole wifi bands (the >>>>>>>>> complete 2.4 GHz band). >>>>>>>>> 2.412,2.417,2.422,....,2.484 GHz >>>>>>>>> >>>>>>>>> I am doing direction finding tests and need to calibrate 4 >>>>>>>>> channels of 2 X310s on the specified frequencies. Both X310s are connected >>>>>>>>> with Octoclock. However, I could only have calibration on 2.4 GHz, 2.45 >>>>>>>>> GHz, 2.5 GHz. For other bands, calibration does not remain after retuning. >>>>>>>>> Is there any specific reason why the calibration only works for every 50 >>>>>>>>> Mhz channel after retuning. I tested with different sampling rates, but the >>>>>>>>> result is the same. Calibration does not remain after retuning. >>>>>>>>> >>>>>>>>> I am using UHD_003.009.002 (installed from synaptic) and ubuntu >>>>>>>>> 16.04. Is there any specific way how I can make it work? >>>>>>>>> >>>>>>>>> Best regards >>>>>>>>> Sanjoy Basak >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> <https://mailtrack.io/> Sent with Mailtrack >>>>>>>>> <https://mailtrack.io/install?source=signature&lang=en&referral=sanjoybasak14@gmail.com&idSignature=22> >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> USRP-users mailing list >>>>>>>>> USRP-users@lists.ettus.com >>>>>>>>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>> >>>>>> >>>>> >>>> >>> >> >