Dear all,

I am trying to investigate the streaming and buffer behaviour of a X310 USRP as 
receiver. To this purpose, one X310 generates a continuous triangle signal with 
each slope spanning over 1e5 samples. For reception I use another X310 which 
receives 1e6 samples in total. Transmission and Reception start simultaneously 
(works fine). The Code is written in C++ on a Ubuntu Notebook. The stream_cmd 
requests continuously packages containing 1e5 samples. The rx_buffers have a 
size of 10000 and are filled in a loop by calls to the recv-function 
(requesting 10000 samples). The samples are written to a file. The reception 
aborts after 1e6 samples have been received - with this parameters after 100 
loop iterations.

Both USRPs use the same sampling rate (0.5 MSps) and each uses a GPSDO as 
reference. From an RF and communication engineering point of view everything 
works fine, but the following error occurs in the streaming/ receiving of the 
samples:

The first triangle in the puls train seems to be received normally, but then 
after ~1.3e5 samples (in the falling slope of the first triangle puls) it is 
suddenly interrupted and starts again from the beginning. This occurs only 
during the first pulse, all subsequently received triangles are correct.

I cannot figure out why the X310 or UHD are mixing up/ repeating samples. I 
tried different streaming modes, different buffer sizes and so on, but nothing 
could solve the problem.

As I'm at my wits' end, I would appreciate any help.

Best regards,
Nicolai

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