Dear all, I am testing the phase offset between two Rx channels of B210. For this case, I transmit a sine signal with another USRP device and receive it with two RX channels of B210. Then I calculate the phase offset between channels. The problem is the phase offset changes whenever I reset the receiver. So it gives a random phase offset on each device turn on. Is this normal? If yes, what is the reason for this random phase offset. Since both channels share the same LO, where this "random" phase offset come from? Thank you... Anketek Signature ------------------------------------------------------------------------ /*Ufuk Tamer */

On 03/24/2015 03:12 PM, Ufuk Tamer via USRP-users wrote: > Dear all, > > I am testing the phase offset between two Rx channels of B210. For > this case, I transmit a sine signal with another USRP device and > receive it with two RX channels of B210. Then I calculate the phase > offset between channels. The problem is the phase offset changes > whenever I reset the receiver. So it gives a random phase offset on > each device turn on. > > Is this normal? If yes, what is the reason for this random phase > offset. Since both channels share the same LO, where this "random" > phase offset come from? > > Thank you... > > Anketek Signature > ------------------------------------------------------------------------ > /*Ufuk Tamer > */ What version of UHD are you using? How are you doing the two-channel receive?

I am using the latest version. I have a simple GRC flow graph that takes two channel I&Q data and then processing this data in Octave. And every time I turn on the receiver (tx & rx locations are fixed), I get different phase offset between two rx channels. In order to apply direction of arrival (DOA) technique, I have to first use a reference signal to detect this random phase offset, remove it and then estimate the angle of transmitter. On 24.3.2015 22:12, Marcus D. Leech via USRP-users wrote: > On 03/24/2015 03:12 PM, Ufuk Tamer via USRP-users wrote: >> Dear all, >> >> I am testing the phase offset between two Rx channels of B210. For >> this case, I transmit a sine signal with another USRP device and >> receive it with two RX channels of B210. Then I calculate the phase >> offset between channels. The problem is the phase offset changes >> whenever I reset the receiver. So it gives a random phase offset on >> each device turn on. >> >> Is this normal? If yes, what is the reason for this random phase >> offset. Since both channels share the same LO, where this "random" >> phase offset come from? >> >> Thank you... >> >> Anketek Signature >> ------------------------------------------------------------------------ >> /*Ufuk Tamer >> */ > What version of UHD are you using? > > How are you doing the two-channel receive? > > > > > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com Anketek Signature ------------------------------------------------------------------------ Anketek Elektronik Teknoloji /*Ufuk Tamer */ Research and Development Engineer Anketek Elektronik Teknoloji Tic. San. Ltd. Sti. KOSGEB ODTÜ-TEKMER Binası, No: 113 Çankaya, Ankara 06800, Türkiye Web: Anketek <http://www.anketek.com.tr/> E-mail: ufuk.tamer@anketek.com.tr <mailto:ufuk.tamer@anketek.com.tr> Phone: +90 312 210 13 00 - 113

I am using the latest version. I have a simple GRC flow graph that takes two channel I&Q data and then processing this data in Octave. And every time I turn on the receiver (tx & rx locations are fixed), I get different phase offset between two rx channels. In order to apply direction of arrival (DOA) technique, I have to first use a reference signal to detect this random phase offset, remove it and then estimate the angle of transmitter. On 24.3.2015 22:12, Marcus D. Leech via USRP-users wrote: > On 03/24/2015 03:12 PM, Ufuk Tamer via USRP-users wrote: >> Dear all, >> >> I am testing the phase offset between two Rx channels of B210. For >> this case, I transmit a sine signal with another USRP device and >> receive it with two RX channels of B210. Then I calculate the phase >> offset between channels. The problem is the phase offset changes >> whenever I reset the receiver. So it gives a random phase offset on >> each device turn on. >> >> Is this normal? If yes, what is the reason for this random phase >> offset. Since both channels share the same LO, where this "random" >> phase offset come from? >> >> Thank you... >> >> Anketek Signature >> ------------------------------------------------------------------------ >> /*Ufuk Tamer >> */ > What version of UHD are you using? > > How are you doing the two-channel receive? > > > > > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com Anketek Signature ------------------------------------------------------------------------ /*Ufuk*/

On 03/24/2015 05:18 PM, Ufuk Tamer wrote: > I am using the latest version. I have a simple GRC flow graph that > takes two channel I&Q data and then processing this data in Octave. > And every time I turn on the receiver (tx & rx locations are fixed), I > get different phase offset between two rx channels. > > In order to apply direction of arrival (DOA) technique, I have to > first use a reference signal to detect this random phase offset, > remove it and then estimate the angle of transmitter. > What are you using for time-synch in the UHD source block? > On 24.3.2015 22:12, Marcus D. Leech via USRP-users wrote: >> On 03/24/2015 03:12 PM, Ufuk Tamer via USRP-users wrote: >>> Dear all, >>> >>> I am testing the phase offset between two Rx channels of B210. For >>> this case, I transmit a sine signal with another USRP device and >>> receive it with two RX channels of B210. Then I calculate the phase >>> offset between channels. The problem is the phase offset changes >>> whenever I reset the receiver. So it gives a random phase offset on >>> each device turn on. >>> >>> Is this normal? If yes, what is the reason for this random phase >>> offset. Since both channels share the same LO, where this "random" >>> phase offset come from? >>> >>> Thank you... >>> >>> Anketek Signature >>> ------------------------------------------------------------------------ >>> /*Ufuk Tamer >>> */ >> What version of UHD are you using? >> >> How are you doing the two-channel receive? >> >> >> >> >> >> _______________________________________________ >> USRP-users mailing list >> USRP-users@lists.ettus.com >> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > Anketek Signature > ------------------------------------------------------------------------ > /*Ufuk*/

I am using the block in default settings so time sync part is in default. On 24.3.2015 23:20, Marcus D. Leech wrote: > On 03/24/2015 05:18 PM, Ufuk Tamer wrote: >> I am using the latest version. I have a simple GRC flow graph that >> takes two channel I&Q data and then processing this data in Octave. >> And every time I turn on the receiver (tx & rx locations are fixed), >> I get different phase offset between two rx channels. >> >> In order to apply direction of arrival (DOA) technique, I have to >> first use a reference signal to detect this random phase offset, >> remove it and then estimate the angle of transmitter. >> > What are you using for time-synch in the UHD source block? > > >> On 24.3.2015 22:12, Marcus D. Leech via USRP-users wrote: >>> On 03/24/2015 03:12 PM, Ufuk Tamer via USRP-users wrote: >>>> Dear all, >>>> >>>> I am testing the phase offset between two Rx channels of B210. For >>>> this case, I transmit a sine signal with another USRP device and >>>> receive it with two RX channels of B210. Then I calculate the phase >>>> offset between channels. The problem is the phase offset changes >>>> whenever I reset the receiver. So it gives a random phase offset on >>>> each device turn on. >>>> >>>> Is this normal? If yes, what is the reason for this random phase >>>> offset. Since both channels share the same LO, where this "random" >>>> phase offset come from? >>>> >>>> Thank you... >>>> >>>> Anketek Signature >>>> ------------------------------------------------------------------------ >>>> /*Ufuk Tamer >>>> */ >>> What version of UHD are you using? >>> >>> How are you doing the two-channel receive? >>> >>> >>> >>> >>> >>> _______________________________________________ >>> USRP-users mailing list >>> USRP-users@lists.ettus.com >>> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >> >> Anketek Signature >> ------------------------------------------------------------------------ >> /*Ufuk*/ > Anketek Signature ------------------------------------------------------------------------ /*Ufuk */