Wireless position location and tracking system
Techniques for accurate position location and tracking suitable for a wide range of facilities in variable environments are disclosed. In one aspect, a system for position location comprises a plurality of sensors (e.g. a network monitor, an environment sensor) for generating measurements of a plurality of sources, a plurality of objects or tags, each object generating measurements of the plurality of sources, and a processor for receiving the measurements and generating a position location for one or more objects in accordance with the received measurements. In another aspect, a position engine comprises a mapped space of a physical environment, and a processor for updating the mapped space in response to received measurements. The position engine may receive second measurements from an object within the physical environment, and generate a position location estimate for the object from the received second measurements and the mapped space.
1. A system for locating and tracking at least one object within an indoor facility, the system comprising:
a tag associated with the at least one object; the tag configured to generate a periodic wireless signal comprising at least an identification of the tag;
a plurality of network monitors, each of the plurality of network monitors attached to a wall outlet at a known location of the indoor facility, the periodic wireless signal from the tag received at the plurality of network monitors;
a plurality of positioning engines, each of the plurality of positioning engines configured to receive a transmissions from the plurality of network monitors, the transmissions comprising information for the periodic wireless signal from the tag comprising identification of the tag and a signal strength of the periodic wireless signal from the tag, each of the plurality of positioning engines configured to produce a location hypothesis for an object based on the transmissions from the plurality of network monitors and a map of physical barriers of the indoor facility; and
a master positioning engine for receiving the plurality of location hypotheses from each of the plurality of positioning engines, the master positioning engine configured to evaluate each of the plurality of location hypotheses for the object to determine if a location hypothesis of the plurality of location hypotheses should be included in a location determination for the object, and to generate a location estimate for the object based on the plurality of location hypotheses included in the location determination.
2. The system according to claim 1 wherein:
a first one of the plurality of positioning engines determines a single-dimension location estimate for the object; and
a second one or more of the plurality of positioning engines determines a two-dimensional location estimate for the object in response to the determined single-dimension location estimate and one or more measurements received from the object.
3. The system according to claim 1 wherein at least one of the location hypothesis is computed according to a received displacement vector for the tag generated by the tag.
4. The system according to claim 1 wherein location hypothesis is computed according to one or more previous location hypotheses for the object.
5. A system for locating and tracking at least one object within an indoor facility, the system comprising:
a plurality of beacon emitters positioned within the indoor facility, each of the plurality of beacon emitters generating a radiofrequency signal;
a plurality of network monitors, each of the plurality of network monitors attached to a wall outlet at a known location of the indoor facility and generating a first plurality of measurements comprising data including signal strength from each of the plurality of beacon emitters received by each of the plurality of network monitors;
a plurality of mobile objects, each of the plurality of mobile objects having a tag attached thereto, each tag generating a second plurality of measurements comprising data including signal strength from each of the plurality of beacon emitters received by the tag;
a plurality of positioning engines, each of the plurality of positioning engines configured to receive a transmissions from the plurality of network monitors, the transmissions comprising information for the periodic wireless signal from the tag comprising identification of the tag and a signal strength of the periodic wireless signal from the tag, each of the plurality of positioning engines configured to produce a location hypothesis for each of the plurality of mobile objects based on the transmissions from the plurality of network monitors, transmissions from each tag of the plurality of mobile objects and a map of physical barriers of the indoor facility; and
a master positioning engine for receiving a plurality of location hypotheses from each of the plurality of positioning engines, the master positioning engine configured to evaluate each of the plurality of location hypotheses for each of the plurality of mobile objects to determine if a location hypothesis of the plurality of location hypotheses should be included in a location determination for each of the plurality of mobile objects, and to generate a location estimate for each of the plurality of mobile objects based on the plurality of location hypotheses included in the location determination.
6. The system according to claim 5 wherein the plurality of positioning engines comprises:
a first positioning engine for determining a single-dimension location estimate for the at least one object; and
a second positioning engine for determining a two-dimensional location estimate for the at least one object in response to the determined single-dimension location estimate and one or more of the second plurality of measurements received from the tag associated with the at least one object.
7. The system according to claim 5 wherein at least one of the location hypothesis is computed according to a received displacement vector for the tag generated by the tag.
8. The system according to claim 5 wherein at least one of the location hypothesis is computed according to one or more previous location hypotheses for the object.
9. A method for locating and tracking at least one object within an indoor facility, the indoor facility including a plurality of beacon emitters positioned therein, a plurality of network monitors, and a tag associated with the at least one object, each beacon emitter generating a radiofrequency signal, each network monitor attached to a wall outlet at a known location of the indoor facility and generating a first plurality of measurements comprising data including signal strength from each of the plurality of beacon emitters received by the network monitor, the tag generating a second plurality of measurements comprising data including signal strength from each of the plurality of beacon emitters received by the tag, the method comprising:
generating a first plurality of measurements comprising data including signal strength from each of a plurality of beacon emitters received by a plurality of network monitors;
generating a second plurality of measurements comprising data including signal strength from each of the plurality of beacon emitters received by a plurality of tags, each of the plurality of tags attached to a mobile object;
generating a plurality of location hypotheses for each of a plurality of mobile objects within the indoor facility, each of the plurality of location hypotheses generated by a positioning engine of a plurality of positioning engines, each of the plurality of location hypotheses based on the transmissions from the plurality of network monitors, transmissions from each tag of the plurality of mobile objects and a map of physical barriers of the indoor facility; and
generating a location estimate based on one or more of the plurality of location hypotheses at a master positioning engine, the master positioning engine configured to evaluate each of the plurality of location hypotheses for each of the plurality of objects to determine if a location hypothesis of the plurality of location hypotheses should be included in a location determination for each of the plurality of mobile objects, and to generate the location estimate for each of the plurality of mobile objects based on the plurality of location hypotheses included in the location determination.
10. The method according to claim 9 wherein at least one of the location hypothesis is computed according to a received displacement vector for the tag generated by the tag.
11. The method according to claim 9 wherein at least one of the location hypothesis is computed according to one or more previous location hypotheses for the object.