Re: [USRP-users] X310 frequency accuracy spec

Thank you Marcus. So, +-0.01ppb is right.If two USRP x310(both of them use OCXO) are communicating each other via coaxial cable at the frequency 1GHz, the receiver usrp x310 have to get the center frequency from (1GHz - 0.02Hz) to (1GHz + 0.02Hz). I mean, the frequency offset should be within +

Re: [USRP-users] X310 frequency accuracy spec

On 05/02/2018 12:32 AM, Hojoon Yang via USRP-users wrote: Hi, all. In manual, I see the following sentece. "The GPSDO improves the accuracy of the internal frequency reference to 20 ppb, or 0.1 ppb if the GPS is synchronized to the GPS constellation."[1] It said 0.1 ppb if the GPS synchr

[USRP-users] X310 frequency accuracy spec

Hi, all.In manual, I see the following sentece."The GPSDO improves the accuracy  of the internal frequency reference to 20 ppb, or 0.1 ppb if the GPS is synchronized to the GPS constellation."[1]It said 0.1 ppb if the GPS synchronized. However, in the below table, Frequency Accuracy is +-0.01ppb

Re: [USRP-users] UHD C++ Chirp Signal

Hello, Thanks for the reply! However, I am unsure on what to do ( sorry, I am not a programming/USRP expert). Do you mean that I run the tx_bursts.cpp and then it will generate out an actual sample rate. So my code has to use the (usrp->get_tx_rate() ) value and use that value and feedback to

[USRP-users] Minimize latency on X310 using PCIe

Hi, I would like to minimize the absolute latency of the X310 using the PCIe interface. Currently I have a script consisting of two threads, one receives data from RX (and places that data into a buffer) and the second thread transmits that data from the buffer. (Everything is in c++ using UHD

Re: [USRP-users] B200 clocking - Minimum master_clock_rate and DCM ?

That’s a little bit strange Silvain, I wonder if there has been a UHD regression. I eliminated the 5MHz limit in UHD when I did away with the DCM in 2015, and I don’t recall any gotcha’s that might bite you though you end up running the DSP at a crazy low clock frequency which has a knock on ef

[USRP-users] B200 clocking - Minimum master_clock_rate and DCM ?

Hi, It seems that the minimum master_clock_rate for the B200 is fixed to 5 MHz in UHD : static uhd::meta_range_t get_clock_rate_range(void) { //return uhd::meta_range_t(220e3, 61.44e6); return uhd::meta_range_t(5e6, ad9361_device_t::AD9361_MAX_CLOCK_RATE); //5 MHz DCM low

Re: [USRP-users] Revert rfnoc-devel to older commit / update rfnoc-devel to rfnoc-maint HEAD

FYI, the UHD commit number I mentioned previously fails "make test" (an older mailer thread confirms this) which I didn't run originally and manifested runtime problems. And GRC couldn't launch with the GNU Radio version I mentioned (maybe related to that UHD bug). Reverting builds have been shots

Re: [USRP-users] How to define FIR RFnoc block with float taps

Dear Ishai, convert the taps to integers. This typically involves scaling with a power of two (pick one that would allow the matching signal to stay within numerical limits of your internal stream format) and rounding. No magic involved here :) Best regards, Marcus On Tue, 2018-05-01 at 14:31 +00

[USRP-users] How to define FIR RFnoc block with float taps

Hi all, I try to use the FIR filter and define the taps to be float number, but the problem is that the taps must to be integer number. Can someone please help me how solve this issue. Thanks in advance Ishai The information in this e-mail transmission contains proprietary and business sensit

[USRP-users] Turbo Product Codes on USRP E312

Hi everyone, I am using a USRP E312 with GNU Radio 3.7.10.2. GNU Radio has an inbuilt FEC block that supports Turbo Product Codes (TPC). I'm trying to run a flowgraph (completely in simulation) on the E312 that includes a TPC encoder and decoder. The TPC parameters are: parallelism: 0 row encodin