GNU Radio UHD

To ensure the interaction of GNU Radio with RITM SDR USRP, you need to perform several actions.

Create a new flow graph (flowgraph).
Create a receiver. To do this, drag the block UHD: USRP Source from Core/UHD/ go to the graph and set it up:
- for "Device Address" set the SDR IP address;
- for "Ch0: Antenna" set the value "TX/RX";
- to control the flow in real time, you need to transfer the parameters "Ch0: Center Freq (Hz)", "Ch0: Gain Value" in sliders QT GUI Range from Core/GUI Widgets/QT.
  
  As a result, the block UHD: USRP Source should look something like this:
Add a signal output in the time domain QT GUI Time Sink and frequency QT GUI Frequency Sink Along the way Instrumentation/QT/QT GUI Frequency Sink. Connect the output out block UHD: USRP Source and the inputs QT GUI Time Sink and QT GUI Frequency Sink.
Create a transmitter. To do this, drag the block UHD: USRP Sink from Core/UHD/ go to the graph and set it up:
- for "Device Address" set the SDR IP address;
- for "Clock Rate" set the value 30.72 MHz
- create variable_qtgui_TX_GAIN How QT GUI Range and specify it in "Ch0: Gain Value";
- In "Ch0: Cenetr Freq (Hz)" specify variable_qtgui_range_FREQ_CARRIER.
Create a sinusoidal signal source Signal Source Along the way Core/Waveform Generators and set it up:
- for Output Type set the value complex;
- for Sample Rate set the value 10M;
- for Waveform set the value Cosine;
- to adjust the frequency Frequency need to create sin_freq How QT GUI Range;
- to adjust the amplitude Amplitude need to create sin_gain How QT GUI Range.
Connect the output (out) source Signal Source and the entrance (in) transmitter UHD: USRP Sink.

An approximate view of the receiver and transmitter circuit is shown in the figure.
Press start and GNU Radio starts transmitting and receiving the signal. At the top there are sliders with which you can change the parameters of the signal, as well as the parameters RITM SDR USRP.