Total posts : 45366
Perhaps take some cues from the hams. Find out what ham repeaters use for STL links and adopt them to part 15 apps. For those who are unfamiliar with ham repeaters, the owner or trustee can remotely control the repeater with his handie talkie using certain codes. Surely these programs can be adapted to part 15.
Side note, one approach to a STL is to use a DTMF or coded FM link. Say broadcast your signal on 88.1 on FM and you have a FM receiver at the part 15 AM transmitter tuned to 88.1, with a adaptation one could use the DTMF/coded approach where you can set it up that only your 88.1 would open the part 15 using the coded signal and then just contunue to use 88.1 as a pure STL link.
Wireless 802-G is yet another approach using WAP encyption, but now we are talking adding a computer directly at the part 15. It could be done though. Wireless G has interesting applications as one can use a high gain antenna to direct the signal to the part 15.