Doesn't seem to require ongoing communication after firing. The RPi is used to monitor the sound and redirect the rocket toward the loudest thing in the immedia

Doesn't seem to require ongoing communication after firing. The RPi is used to monitor the sound and redirect the rocket toward the loudest thing in the immediate environment(?). A helicopter that is close enough to be firing on you is going to be making quite a racket. I am assuming that sound is used because sound sensors are cheap and these are likely to be fire and forget type weapons.