Rescue beacon: follow the signal to the survivor — if you can
The survivor's beacon broadcasts. The rescuer reads signal strength (RSSI) and moves toward higher signal strength. But walls bounce the signal, and the echoes can make it weaker as you get closer.
Drag the rescuer. Watch RSSI as you approach — you'll pass through dead spots where the bounced signal cancels the direct one, even though you're getting closer.
signal strength (RSSI)
—
—
direct path (survivor → rescuer)
wall-bounce path
The graph plots RSSI over time as you walk. "Closer" should mean "louder" — multipath breaks that.