alt Hacker News>For me a number station needs sends a message to be a number station, not a key.
We don't know that it's a key that's being sent. For all we know, it could be just random data. Obviously it's most likely not random data, but ciphertext. Either way, we have no idea what the message is.
It is kind of like a number station but it's meant for machine to machine communication of commands, keys, and probably test messages specifically for military GPS receivers. The US government has plenty of other satellites (and the internet) at its disposal for sending messages to people covertly. They don't need to risk screwing up critical infrastructure just to send a message to someone. It also wouldn't be prudent to give a secret agent something so obviously a piece of spycraft. There's plenty of off-the-shelf radio receivers you can buy worldwide that would be capable of picking up an encoded message transmitted by a passing satellite.