1.1 Scope This standard defines the Air Interface Protocol for a location system that provides zone location information utilizing a device that generates a radio frequency transmission that can be received at a minimum of 100 meters open-field separation between the transmitter and receiver and is fully compliant with United States radio frequency regulatory requirements. The 433-MHz systems utilizing the Air Interface Protocol defined by this document will allow the user to manage assets within the infrastructure of the system on a real-time basis. The average location data provided by the system are within 10 meters of the actual location of the transmitting device. The RF transmissions are low power and are compatible with and do not interfere with existing standardized wireless communication networks.