[USRP-users] Fwd: Please add me to the mail list
Hallo Diogo, I had the same Problem. You get no sending-confirmation from the mailing-list and you don't get your own message from the mailing list. Unfortunately even the support of Ettus didn't know that an couldn't helped me. I've had to use a second Mail, to find this out :/ @Ettus: would be great to change this behaviour! So everything is fine, even when a normal forum would be much more structured and helpful than a mailing-list. Am 21.03.19 um 11:05 schrieb Piotr Krysik via USRP-users: > W dniu 21.03.2019 o 10:58, Diogo Botelho Ribeiro Marinho via USRP-users > pisze: >> I am using N310 and i would like to send my questions to the forum. >> >> >> >> So far i am not able to do it. >> >> >> >> > Hi Diogo, > > I beg to disagree. From my perspective it looks that you are able to > send posts to the mailing-list. > > I can even see your post from two days ago (without its subject however). > > -- > Best Regards, > Piotr Krysik > > > > ___ > 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
Re: [USRP-users] Phase drift issue of N310
On 03/21/2019 07:08 AM, Damon wrote: Hi Marcus, Thank you for your reply. I compared the USRP configuration of your grc file with that of mine. I found that the key to solve this issue is set_time_next_pps or set_time_unknow_pps should be called. I don't know why those two functions have an effect on phase error. I haven't found any special description of these two functions in the N310 manual. Best regards, Damon They'll have an effect on initial phase error, because each half of the N310 has its own timekeeper. If those aren't brought into alignment, then the sample streams will be unaligned. But that should have no effect on ongoing phase drift--ONLY on initial phase error. On 2019/3/21 上午1:07, Marcus D. Leech wrote: On 03/20/2019 12:55 PM, Damon wrote: Hi Marcus, Thanks for your reply. Yes, it happen with any other frequency changes, not only 460.01M and 469.03Mhz. I'm building a 4-channel coherent receiving system with n310. It needs to compensate the phase errors of multiple receiving channels. So I need to measure the phase errors first and then compensate them. But in the range of 100MHz bandwidth (from center_freq-50MHz to center_freq+50MHz), the phase difference of two receiving channels of different dboards varies too much with frequency, so it's very difficult to compensate the phase errors. As a contrast, the phase errors of the two receiving channels of X310 with ubx vary very samll with frequency, so it is easy to compensate the phase difference. Looking forward to your test results Best regards, Damon I used the attached script. Now, I'm only looking at +/- 2MHz, rather than your 100Mhz bandwidth. I found that the phase noise and offset did not change noticably tuning across the entire 4Mhz band. I don't have a machine fast enough here to sweep my TX across 100Mhz, but with the N310 RX at a fixed tuning, and sweeping the TX (in this case, a Marconi transceiver test set), I did not see any significant phase shift or change in mutual phase noise as the TX swept across the 4MHz band. On 2019/3/20 上午10:40, Marcus D. Leech wrote: On 03/19/2019 09:12 PM, Damon wrote: Hi Marcus, The phase responses of two channels of different dboards (ubx-160) in a X310 are very consistent. When the frequency of transmitting signal changes from 460.01MHz to 460.03Mhz, the phase difference between two RX channels of different dboards in X310 remains unchanged. But for the phase difference between two RX channels of different dboards of N310, there are dozens or hundreds degree of changes. Can you try to reproduce the test and help me to figure out how to solve it? I'm not sure if it's a hardware bug, a driver bug or USRP setup problem. I cannot imagine a hardware or driver bug that could produce this behavior. It would mean that the receiver was somehow changing LO frequency when the TX frequency changed. Does this happen with *other* frequency changes, or just 460.01<--->460.03. I wonder if you have an interfering signal that is being "uncovered" by TX frequency change, and you're simply measuring that interfering signal? The only other thing that occurs to me is filtering that is extremely non-linear phase. But that would create such a mess that most applications would likely not work--clearly they do. I can try to reproduce in my lab tomorrow, but, like the last tests I did, I very much expect to not be able to reproduce. Best regards, Damon On 2019/3/19 上午6:10, Marcus D. Leech wrote: On 03/18/2019 01:26 PM, Damon wrote: Hi Marcus, Sorry, I can't reproduce the first observation in this discussion thread. A new problem about phase response has arisen. I am testing the phase coherence performance of four receiving channels of N310. A B200 is transmitting single tone continuous wave to a one to four splitter. The 4 outputs of the splitter are connected to 4 RX channels of N310. Attached please find the GRC file of this test. The RX frequency of 4 channels of N310 is set to 460MHz, and keep running in the test. The TX frequency of B200 is set to 460.02MHz first, and then to 460.03MHz. I thought the phase difference between different dboards would change very little when the signal frequency difference is very small, similar to the performance of X310. However, the fact is that the phase difference between the two dboards of N310 varies considerably with the signal frequency transmission. For example, in the attached picture, when the signal frequency is 460.01MHz, the phase difference between channel 2 and channel 0 is -118 degrees, the phase difference between channel 1 and channel 0 is 0 degrees; when the transmission frequency is adjusted to 460.03MHz, the phase difference between channel 2 and channel 0 is 117 degrees, and the phase difference between channel 1 and channel 0 is 0 degrees. It is very difficult to understand that the phase difference of two receiving channels
Re: [USRP-users] Phase drift issue of N310
Hi Marcus, Thank you for your reply. I compared the USRP configuration of your grc file with that of mine. I found that the key to solve this issue is set_time_next_pps or set_time_unknow_pps should be called. I don't know why those two functions have an effect on phase error. I haven't found any special description of these two functions in the N310 manual. Best regards, Damon On 2019/3/21 上午1:07, Marcus D. Leech wrote: On 03/20/2019 12:55 PM, Damon wrote: Hi Marcus, Thanks for your reply. Yes, it happen with any other frequency changes, not only 460.01M and 469.03Mhz. I'm building a 4-channel coherent receiving system with n310. It needs to compensate the phase errors of multiple receiving channels. So I need to measure the phase errors first and then compensate them. But in the range of 100MHz bandwidth (from center_freq-50MHz to center_freq+50MHz), the phase difference of two receiving channels of different dboards varies too much with frequency, so it's very difficult to compensate the phase errors. As a contrast, the phase errors of the two receiving channels of X310 with ubx vary very samll with frequency, so it is easy to compensate the phase difference. Looking forward to your test results Best regards, Damon I used the attached script. Now, I'm only looking at +/- 2MHz, rather than your 100Mhz bandwidth. I found that the phase noise and offset did not change noticably tuning across the entire 4Mhz band. I don't have a machine fast enough here to sweep my TX across 100Mhz, but with the N310 RX at a fixed tuning, and sweeping the TX (in this case, a Marconi transceiver test set), I did not see any significant phase shift or change in mutual phase noise as the TX swept across the 4MHz band. On 2019/3/20 上午10:40, Marcus D. Leech wrote: On 03/19/2019 09:12 PM, Damon wrote: Hi Marcus, The phase responses of two channels of different dboards (ubx-160) in a X310 are very consistent. When the frequency of transmitting signal changes from 460.01MHz to 460.03Mhz, the phase difference between two RX channels of different dboards in X310 remains unchanged. But for the phase difference between two RX channels of different dboards of N310, there are dozens or hundreds degree of changes. Can you try to reproduce the test and help me to figure out how to solve it? I'm not sure if it's a hardware bug, a driver bug or USRP setup problem. I cannot imagine a hardware or driver bug that could produce this behavior. It would mean that the receiver was somehow changing LO frequency when the TX frequency changed. Does this happen with *other* frequency changes, or just 460.01<--->460.03. I wonder if you have an interfering signal that is being "uncovered" by TX frequency change, and you're simply measuring that interfering signal? The only other thing that occurs to me is filtering that is extremely non-linear phase. But that would create such a mess that most applications would likely not work--clearly they do. I can try to reproduce in my lab tomorrow, but, like the last tests I did, I very much expect to not be able to reproduce. Best regards, Damon On 2019/3/19 上午6:10, Marcus D. Leech wrote: On 03/18/2019 01:26 PM, Damon wrote: Hi Marcus, Sorry, I can't reproduce the first observation in this discussion thread. A new problem about phase response has arisen. I am testing the phase coherence performance of four receiving channels of N310. A B200 is transmitting single tone continuous wave to a one to four splitter. The 4 outputs of the splitter are connected to 4 RX channels of N310. Attached please find the GRC file of this test. The RX frequency of 4 channels of N310 is set to 460MHz, and keep running in the test. The TX frequency of B200 is set to 460.02MHz first, and then to 460.03MHz. I thought the phase difference between different dboards would change very little when the signal frequency difference is very small, similar to the performance of X310. However, the fact is that the phase difference between the two dboards of N310 varies considerably with the signal frequency transmission. For example, in the attached picture, when the signal frequency is 460.01MHz, the phase difference between channel 2 and channel 0 is -118 degrees, the phase difference between channel 1 and channel 0 is 0 degrees; when the transmission frequency is adjusted to 460.03MHz, the phase difference between channel 2 and channel 0 is 117 degrees, and the phase difference between channel 1 and channel 0 is 0 degrees. It is very difficult to understand that the phase difference of two receiving channels of two different dboards has changed by 235 degrees with the signal frequency change of 20 KHz. The phase difference of two receiving channels of the same dboard is basically unchanged. Best regards, Damon Since the LO on the daughterboards has no idea that you've changed input frequency, this is clearly a
Re: [USRP-users] Please add me to the mail list
W dniu 21.03.2019 o 10:58, Diogo Botelho Ribeiro Marinho via USRP-users pisze: > > I am using N310 and i would like to send my questions to the forum. > > > > So far i am not able to do it. > > > > Hi Diogo, I beg to disagree. From my perspective it looks that you are able to send posts to the mailing-list. I can even see your post from two days ago (without its subject however). -- Best Regards, Piotr Krysik ___ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
[USRP-users] Please add me to the mail list
I am using N310 and i would like to send my questions to the forum. So far i am not able to do it. Thanks Diogo Marinho ___ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
Re: [USRP-users] Are timed-configuration blocking calls?
Dear All, Does anyone could give me some hint, suggestion, etc. on this issue? Anything would be very helpful. Thanks and Kind Regards, Felipe Augusto On Wed, Mar 13, 2019 at 10:39 PM Felipe Augusto Pereira de Figueiredo wrote: > > Dear all, > > I've got an application that uses timed commands to change Tx > frequency and gain and sent at to schedule the transmission of my > data, however, I noticed that the time it takes for my app to generate > and transfer the data to the USRP increased after the introduction of > the timed configuration. My app works like this > > 1) Generate data at upper layer with timestamp t0+2ms (i.e., send at t0+2ms) > 2) Execute timed configuration (Tx freq. and/or gain) at t0+2ms-300us > (i.e., the 300 us before the actual transmission time) > 3) Encode the data and transfer to USRP. > > Before the introduction of timed configuration the step 3) would take > around 300/400 us but after I started using timed configuration it > went to more than 1 ms. > > Based on what I have explained, my questions are: > > 1) Are timed-configuration blocking calls? > 2) Is there a non-blocking way of doing this? > 3) Is there a way of scheduling data transmission at t0+2ms and timed > config at t0+2ms-300us in the same timed configuration? > > I'm looking for a way to avoid this blockage. I have tried to create a > thread that would only apply the timed config and another one that > would encode data and transmit at the specified time, however, the UHD > seems not to like being played with in separate threads (I have > mutexes in my calls, but is doesn't help). My app crashes with a > message saying UHD was waiting for message 1234 but received > acknowledgement for message 2000. I use jumbo frames (MTU 9000) with > 10 Gb ethernet card and probably the crash is related to aggregation > and or reordering. BTW, I would like to change the MTU size right now. > I would like to find a better solution to the blocking call, if > possible. > > Many thanks in advance, > > Felipe ___ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
