Step 3: CubeSatSim Raspberry Pi Ground Station 

If your ground station and the CubeSatSim are in the same room, any antenna will likely work. The Pi software also has the gain turned up, too.

That’s correct. The CubeSatSim has a Pi Zero inside it. Step 2 installs the software for it. This step is setting up the Ground Station that receives the radio signals from CubeSatSim. You can use your own PC for the Ground Station, or you can use another Raspberry Pi such as the Pi 4.