Tutorial - MBMS Modem with Sample Files

The rt-mbms-modem can be run with sample files. See Sample Files.

Before capturing or running a sample file, make sure that MBMS Modem isn’t running in background. If it is, stop MBMS Modem with systemctl stop 5g-mag-rt-modem.

Capture a sample file

In order to capture sample files, you need to receive a 5G BC signal.

Run the command:

modem -w "PathToSample/samplefile.raw"

to capture the raw I/Q data from the SDR.

Run a sample file

Important: For correct pre-configuring of the MBMS Modem at system startup, it has to be run through systemd once, see https://github.com/5G-MAG/rt-mbms-modem#configuration

Based on the structure of the Service Announcement file the configuration file in /etc/5gmag-rt.conf needs to be adjusted. For details refer to the corresponding documentation.

If you like to start MBMS Modem with a downloaded sample file, you can run the following command:

modem -f "PathToSample/samplefile.raw" -b 10

Notice: -b 10 represents the used bandwith when the sample file was captured (see Manual start/stop). So for a 5 MHz bandwidth sample file you need to adjust the command to -b 5