Installing gr-radio_astro on Ubuntu 20.04

This will install the spectrometer program spectrometer_w_cal.grc as well as other useful radio astronomy GNURadio programs onto a system using Ubuntu 20.04.

Complete the following steps:

1. Open a terminal window in Ubuntu.

2. Install gnuradio external python dependencies and SDR drivers by typing the following and hit enter:

   sudo apt install gnuradio gr-osmosdr airspy python3-h5py python3-ephem git cmake liborc-0.4-dev -y
   

3. To clone the repository: in the terminal, type and Enter: git clone https://github.com/WVURAIL/gr-radio_astro.git

4. Switch to the gr-radio_astro directory: cd gr-radio_astro

5. Switch to the gr-radio_astro 3.8 branch by typing: git checkout gr38

6. Make a build directory: mkdir build, and then move to it: cd build

7. Then run the following in the build directory:

   cmake ..
   sudo make
   sudo make install
   

   Additional Steps for setting the proper Python environment:

8. Open a terminal window.

9. Make sure you are at the home directory (type and Enter cd ). Then type gedit .bashrc to open the .bashrc file in an editor.

10. Scroll to the very bottom of this file, add a blank line, and then copy and paste the following code: export PYTHONPATH=/usr/local/lib/python3/dist-packages:/usr/local/lib/python3.8/dist-packages:$PYTHONPATH

11. Save and close (x in upper right corner).

12. Additionally you can create appropriate symbolic links
    1. Check which python is the installed version of GNURadio by opening gnuradio-companion in a terminal window and click on Help --> About and noting the python version on the dialog box that opens.
    2. Go to the following by typing: cd /usr/local/lib/python3.8/dist-packages or cd /usr/local/lib/python3.9/dist-packages for the appropriate python version.
    3. Type ln -s /usr/local/lib/python3/dist-packages/radio_astro

Check that the Installation was Successful

1. Restart your terminal window. Run the program in Gnuradio:
   • In a terminal window type gnuradio-companion

   • Open the spectrometer_w_cal.grc program as follows:

     File --> Open --> gr-radio_astros --> examples --> *spectrometer_w_cal.grc*

   • Plug an Airspy radio, with the LNA attached, into the USB port. Run the program by hitting the start triangle (“execute the flowgraph”) on the menu bar at top. If no errors occur, you are all set!

How to Update files from the gr-radio_astro gr38 Repository

1. Open the terminal window.

2. From your home directory (cd ), go to the gr-radio_astro folder: cd gr-radio_astro

3. Type git status. Check the “On branch …” statement at the top. You want to be in the gr38 branch. To get there, type git checkout gr38.

4. If a warning message shows up about local changes made that could overwrite files, type git stash.

5. Type git status to check that you are “On branch gr38”.

6. Type git pull.
   • If a warning message shows up about local changes made that could overwrite files, type git stash.
   • Then type git pull again.

7. Change to the build directory: cd build

8. Type rm -rf *. NOTE: Make sure you are in the build directory before typing rm -rf *!

9. Then run the following:

   cmake ..
   sudo make
   sudo make install
   

10. The update is complete.

To Run the __spectrometer_w_cal.grc__ program in Gnuradio After Updating:

1. In a terminal window type gnuradio-companion.

2. Close any previous version of spectrometer_w_cal.grc that might be open in Gnuradio.

3. Open the new version of spectrometer_w_cal.grc from the folder /gr-radio_astro/examples/

   • under File select Open;
   • Navigate to the gr-radio_astro folder.
   • Under examples open DSPIRA; then select spectrometer_w_cal.grc.

4. Connect an Airspy SDR to a USB port, and start the program running (Hit the black triangle at the top middle ribbon bar.)