I'm working in a project, where we are developing a system to detect whether a truck was or wasn't there. Consider that the place is far away from any kind of source as energy, etc., and we need the data at real time on the system, so we will use, in this case, 3g or wifi.
We're going to track 50 trucks, more or less, and up to 10 readers in a range of 10 meters.
We were thinking of using 2.4 Ghz RFID with active tags. The reader would have a raspberry pi to process and send the information to a server.
Is bluetooth also good for this situation (remembering that security is also important)? Or any other kind of technology?