Re: [Discuss-gnuradio] Ettus E310 & MIMO -- data rate?

[Johannes Demel]

Hi Rob,

Am 26.02.19 um 15:51 schrieb Rob Heig:
> Hi,
> 
> I've bought an Ettus E310 board and I am trying to use it for a MIMO 
> project, but I am encountering several issues.
> 
> In particular, I have created a GNU Radio design, compiled it as Python 
> script (as illustrated on the page 
> https://kb.ettus.com/Streaming_processed_data_from_the_E31x_with_GNU_Radio_and_ZMQ),
>  
> modified it (because it was complaining due to a
> TypeError: push_sink_make() takes at most 5 arguments (6 given)
> error with the ZMQ sink) and scp'd to the board.
> 
> What I've found is
> (1) I cannot set an arbitrary sampling rate (for instance 9.1428M), but 
> I am required to set e.g. 4M.
USRPs, like every hardware, is constraint in terms of available sampling 
rates. You should stick with power of 2 divides of the master clock 
rate. Otherwise, the CIC filters on the USRP will corrupt your signal.

> (2) even with small sampling rates (like 2M), and despite a 10MB buffer 
> in between the USRP source and the ZMQ sink, the system keeps overflowin
> 
> The design I'm using is depicted here: https://ibb.co/GVJxwcm
> 
> - Am I doing anything wrong?
> - What is the sampling rate I am supposed to achieve?
> 
> Thanks a lot in advance!
> Best,
> Rob
> 
> _______________________________________________
> Discuss-gnuradio mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>