Time and Frequency Domain analysis of a Signal

Open GNU Radio Companion using this command

$ gnuradio-companion

An untitled GRC window should open.


1. Double click on the options block. Type project title and Author Name. Set General options to QT GUI. Click OK.

2. On the right side of the window by expanding the wave generator category click on signal source.

3. Now similarly place QT GUI Sink. Connect source and sink to connect. By Pressing F5 generate flow graph warning will be display and ask for throttle block to control the flow. Place throttle block between the source and sink.

4. Now press F5 to generate the Flow graph and F6 to execute the flow graph. A window will appear showing the Frequency of the signal. There will be tabs of Frequency Display , Waterfall Display , Time Domain Display and Constellation Display.

5. Now by using QT GUI Range change the frequency of the signal at runtime. For this on the right side of the window click on GUI Widgets ->QT-> QT GUI Range.

6. Double click on the QT GUI Range block and copy the ID of the block. Now double click on the Signal source and paste in the frequency box.

7. Now execute the flow graph by pressing F5 and execute the flow graph by clicking F6 now you can change the frequency runtime. By changing the frequency analyze the signal in all four blocks.