> Is there currently human technology that does anything similar to this?
Steganography. Not "background", in the sense that images are generally considered useful, but it is hiding information in a place that a casual onlooker would not think to look.
> Encryption is applied on the data layers not to hide that something is being transmitted, but what is being transmitted.
That's exactly why this encryption would be strong. Initially, no one thinks to look for signals that don't look like signals.
Steganography. Not "background", in the sense that images are generally considered useful, but it is hiding information in a place that a casual onlooker would not think to look.
> Encryption is applied on the data layers not to hide that something is being transmitted, but what is being transmitted.
That's exactly why this encryption would be strong. Initially, no one thinks to look for signals that don't look like signals.