I’m looking to see if there is a way to legally retrieve location data for EMS calls. I know a lot of the ones in my area transmit call location to devices in the ambulance. I work in a hospital and it would be nice to see what they are responding to in our area.
"Back in the day", these MDT messages were usually sent over a specific data channel. Our county had an 800MHz channel countywide that would send/receive messages to the fire department. It wasn't encrypted, but it was a specific system that you had to know how to work with. It was also very, very slow speed data, like 9600baud. Only good for short text/address info.
That system has long since been shut down and everyone is using cellular for cellular data. More bandwidth, more coverage, and cheaper to maintain. Some big cities have their own networks, but most are just running on one of the existing cellular networks.
You won't be able to listen in on it. The LTE data is encrypted for all users, not just public safety.
The only way to get that data, legally or otherwise, is to have the agency hook you up with a connection to their system. If you are one of the hospitals they work with, that should be an easy question to ask.
