Bluetooth low energy (BLE) real-time location system (RTLS) having tags, beacons and bridges, that use a combination of motion detection and RSSI measurements to determine room-location of the tags
First Claim
1. A real-time location system (RTLS) having tags, beacons, bridges, and a location server for providing people and asset-tag locating, comprising:
- at least one beacon equipped with a motion sensor, that uses the motion sensor to include a history of motion status sensed in a beacon'"'"'s room, embedded in radio transmissions from the at least one beacon;
at least one bridge for receiving location-update messages from at least one tag, and measuring multiple characteristics of the received location-update messages, including received signal strength, and forwarding those location-update messages to a central server;
at least one tag for listening for radio transmissions from the beacons, and measuring multiple characteristics of the received transmissions, including received signal strength and the beacons'"'"' indication of motion status in the beacon'"'"'s room, where patterns of accelerometer-sensed-motion status of the tag are compared to patterns of the motion status in the beacons'"'"' transmissions, and location-update messages are transmitted to the at least one bridge; and
a central location server utilizing a plurality of location-determining methods comprising;
a first location method for determining a first location estimate for the at least one tag, based on radio characteristics of BLE beacon signals emitted by at least one beacon in fixed locations and received by the at least one tag, and transmitted to the central location server;
a second location method for determining a second location estimate for the at least one tag, based on comparing changes in the history of motion status in the beacons'"'"' rooms, and the coincident history of changes in accelerometer-determined motion status of the at least one tag that is likely in the room; and
a third location method for combining the first location estimate and second location estimate to determine a location result for the at least one tag.
4 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates generally to a real-time location system (RTLS) and more particularly to a Bluetooth Low Energy (BLE) RTLS having tags, bridges, and beacons. To determine which room a tag is in, beacons broadcast BLE advertisements containing motion-status information about recent history of perceived motion in a room as determined from a motion sensor in the beacon. Tags report received signal strength indications (RSSI) from nearby beacons, motion-in-room status sensed and reported by those beacons, plus their own motion status based on a tag-based accelerometer. A series of location-engine steps estimates the room-location of the tags based on a combination of RSSI analysis, and a comparison of tag-motion history to the perceived and recorded motion-status in a room. The analysis of tag-motion history and motion-in-room status produces a better estimate of room-level location of the tag than an RSSI estimate can produce alone.
-
Citations
13 Claims
-
1. A real-time location system (RTLS) having tags, beacons, bridges, and a location server for providing people and asset-tag locating, comprising:
-
at least one beacon equipped with a motion sensor, that uses the motion sensor to include a history of motion status sensed in a beacon'"'"'s room, embedded in radio transmissions from the at least one beacon; at least one bridge for receiving location-update messages from at least one tag, and measuring multiple characteristics of the received location-update messages, including received signal strength, and forwarding those location-update messages to a central server; at least one tag for listening for radio transmissions from the beacons, and measuring multiple characteristics of the received transmissions, including received signal strength and the beacons'"'"' indication of motion status in the beacon'"'"'s room, where patterns of accelerometer-sensed-motion status of the tag are compared to patterns of the motion status in the beacons'"'"' transmissions, and location-update messages are transmitted to the at least one bridge; and a central location server utilizing a plurality of location-determining methods comprising; a first location method for determining a first location estimate for the at least one tag, based on radio characteristics of BLE beacon signals emitted by at least one beacon in fixed locations and received by the at least one tag, and transmitted to the central location server; a second location method for determining a second location estimate for the at least one tag, based on comparing changes in the history of motion status in the beacons'"'"' rooms, and the coincident history of changes in accelerometer-determined motion status of the at least one tag that is likely in the room; and a third location method for combining the first location estimate and second location estimate to determine a location result for the at least one tag. - View Dependent Claims (2, 3, 4)
-
-
5. A real-time location system (RTLS) having tags, beacons, bridges, and a location server for providing people and asset-tag locating, comprising:
-
at least one beacon for transmitting Bluetooth low energy (BLE) advertisements, equipped with a motion sensor and transmitting recent history of motion status sensed in a beacon room; at least one bridge for receiving location-update messages from at least one tag and measuring multiple characteristics of the received location-update messages, including received signal strength, and a motion sensor for determining motion status in the bridge'"'"'s room; at least one tag for listening for BLE advertisements from the beacons and measuring multiple characteristics of the received advertisements, including received signal strength and a series of advertisements of motion status in the beacon'"'"'s room, where accelerometer-sensed-motion status of the tag is compared to the motion status in the beacons'"'"' advertisements, and location-update messages are transmitted to the at least one bridge; a central location server utilizing a plurality of location-determining methods comprising; a first location method for calculating a first location estimate for the at least one tag, based on radio characteristics of BLE beacon signals emitted by at least one beacon in fixed locations and received by the at least one tag, and transmitted to the central location server; a second location method for calculating a second location estimate for the at least one tag, based on comparing changes in the history of motion status in the beacons'"'"' rooms, optional changes in the history of motion changes in the bridges'"'"' rooms, and the coincident history of changes in accelerometer-determined motion status of the at least one tag that is likely in the room; and a third location method for combining the first location estimate and second location estimate to determine a location result for the at least one tag. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13)
-
Specification