Device tracking with radio ranging and sensor functions
Methods and systems for identifying device positions include measuring radio signal strength information between devices. Inertial information is measured for the devices. The radio signal strength information and the inertial information are fused to determine relative locations between the devices. The relative locations are oriented to a fixed anchor node. Elevation is estimated for the plurality of devices using pressure sensor information.
1. A computer-implemented method for identifying device positions, comprising:
measuring radio signal strength information between a plurality of devices;
measuring inertial information for the plurality of devices;
fusing the radio signal strength information and the inertial information to determine relative locations between the plurality of devices;
orienting the relative locations to a fixed anchor node; and
estimating elevation for the plurality of devices using pressure sensor information, including correlating changes in pressure sensor measurements for a first device of the plurality of devices with movement of the first device between floors of a building and filtering out a change in pressure sensor measurements based on the radio signal strength information by comparing elevation estimates for devices having strong signal strengths to the first device.
2. The method of claim 1 , wherein estimating elevation further includes filtering out the change in pressure sensor measurements based on the inertial information.
3. The method of claim 2 , wherein filtering out the change in pressure sensor measurements based on the inertial information includes determining that the change in pressure sensor measurements is not temporally correlated with motion of the first device in a vertical axis.
4. The method of claim 1 , wherein fusing the radio signal strength information and the inertial information is performed using a Kalman filter.
5. The method of claim 1 , wherein fusing the radio signal strength information and the inertial information includes determining a displacement from the inertial information.
6. The method of claim 5 , wherein fusing the radio signal strength information and the inertial information further includes aligning the displacement with the spatial information using an orientation to the Earth's magnetic poles.
7. The method of claim 5 , wherein fusing the radio signal strength information and the inertial information includes resetting the displacement using the radio signal strength information to decrease noise in the inertial information.
8. A computer-implemented method of deploying resources in an interior space, comprising:
identifying a plurality of device positions within an interior space by fusing radio signal strength information and inertial information from a plurality of devices to determine relative locations between the plurality of devices;
orienting the relative locations to a fixed anchor node;
estimating elevation for the plurality of devices using pressure sensor information, including correlating changes in pressure sensor measurements for a first device of the plurality of devices with movement of the first device between floors of a building and filtering out a change in pressure sensor measurements based on the radio signal strength information by comparing elevation estimates for devices having strong signal strengths to the first device;
generating a map of the interior space with the device positions; and
deploying resources to the interior space based on the map.
9. A system for identifying device positions, comprising:
a hardware processor; and
a memory that stores a computer program which, when executed by the hardware processor, causes the hardware processor to:
measure radio signal strength information between a plurality of devices;
measure inertial information for the plurality of devices;
fuse the radio signal strength information and the inertial information to determine relative locations between the plurality of devices;
orient the relative locations to a fixed anchor node; and
estimate elevation for the plurality of devices using pressure sensor information, including a correlation of changes in pressure sensor measurements for a first device of the plurality of devices with movement of the first device between floors of a building with a change in pressure sensor measurements being filtered out based on the radio signal strength information by comparison of elevation estimates for devices having strong signal strengths to the first device.
10. The system of claim 9 , wherein the computer program further causes the hardware processor to filter out the change in pressure sensor measurements based on the inertial information.
11. The system of claim 10 , wherein the computer program further causes the hardware processor to determine that the change in pressure sensor measurements is not temporally correlated with motion of the first device in a vertical axis.
12. The system of claim 9 , wherein the computer program further causes the hardware processor to determine a displacement from the inertial information.
13. The system of claim 12 , wherein the computer program further causes the hardware processor to align the displacement with the spatial information using an orientation to the Earth's magnetic poles.
14. The system of claim 12 , wherein the computer program further causes the hardware processor to reset the displacement using the radio signal strength information to decrease noise in the inertial information.