A REAL-TIME LOCATION SYSTEM (RTLS) THAT USES A COMBINATION OF EVENT SENSORS AND RSSI MEASUREMENTS TO DETERMINE ROOM-AND-BAY-LOCATION OF TAGS

摘要

A real-time location system (RTLS) includes tags, bridges, room-level and bay-level event sensors and a location engine. To determine which room or bay a tag is in, room-level and bay-level event sensors sense motion events in the room or bay, transmit the motion event reports to a location engine, and/or tags. Tags contain an accelerometer, to sense motion of the tags. A series of location-engine steps estimates the room-level or bay-level-location of the tags based on a combination of received signal-strength analysis, and a comparison of tag-motion status to the perceived motion events in a room or bay. The analysis of tag- motion status and motion-in-room and motion-in-bay events produces a better estimate of room-level or bay-level location of the tag than a received-signal- strength estimate can produce alone.