sdr modem
sdr-modem is a modem for software defined radios. It is written in C and use libvolk for performance optimisations. It can be especially useful when working together with sdr-server and omnidirectional antenna. r2cloud can schedule and receive many observations that will queue on the demodulator. With sdr-modem as a demodulator all these observations will be processed really fast. ~10 minutes for jradio vs ~40 seconds for sdr-modem.
sudo apt-get update
sudo apt-get install sdr-modem
Configuration is manual. Edit ~/.r2cloud file and add/change the following line:
satellites.demod.GFSK=SDRMODEM
Switch to file-based RX by editing the file:
sudo nano /etc/sdr-modem/config.conf
And update RX type:
rx_sdr_type="file"
Switch unix user from root to pi for sdr-modem service:
sudo systemctl edit sdr-modem
Add the following lines:
[Service]
User=pi
Group=pi
Make sure sdr-modem is running:
sudo systemctl restart sdr-modem
Restart r2cloud to pick-up new settings:
sudo systemctl restart r2cloud
After switching to sdr-modem the average load dropped significantly (4th of June):
