Re: USRP B210 overflow and underflow

[Marcus D. Leech]

On 29/12/2022 10:56, Karen young wrote:
> Hi,
>
> I am using a USRP B210 to transmit and receive pulse signals using 
> attached antennas, and try to measure the phase delay between the 
> transmitted and received signals. I do not understand why the 
> following problems are happening. What can I do to fix them? Attached 
> is the model.
>
> 1. The usrp_source overflow and usrp_sink underflow errors occur 
> frequently, the received signal (in Red) is jumping accordingly as 
> shown in Fig 1.
>
> 2. Since the transmitted signal is positive pulse, I am expecting the 
> received signal is also positive. While the received signals are: 
> sometimes positive peak, sometimes negative peaks as shown in Fig 2.
>
> Thanks
> Karen
Overruns and Underruns are caused by your computer being unable to "keep 
up" with the sample streaming requirements of
  the hardware.

You might add:

num_recv_frames=256
num_send_frames=256

To your device arguments, which can help "ride through" short-term 
performance insufficiency.