# US 11,029,161 B2 · Position determination device and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,029,161 B2 - Document ID: US11029161B2 - Status: Granted - Kind: B2 - Application number: 15/758,637 - Filed: 2016-09-16 - Published: 2018-09-27 - Granted: 2021-06-08 - Earliest claimed: 2015-09-16 - Assignees: Sony Corporation - Applicants: Sony Corporation - Inventors: Rolf Noethlings; Ben Eitel - Web page: https://patentgrep.com/patent/US11029161B2 ## CPC - G01C 21/206: {specially adapted for indoor navigation} - G01C 21/08: involving use of the magnetic field of the earth - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) ## Abstract A position determination device, for example for indoor positioning, includes data input circuitry configured to obtain at least one magnetic field vector sensed by a magnetic sensor, data processor circuitry configured to determine the magnetic magnitude and a further magnetic parameter of the at least one obtained magnetic field vector, comparison circuitry configured to compare the determined magnetic magnitude with a predetermined magnetic magnitude map of a region around the magnetic sensor to obtain a first estimate of the sensor position and to compare the determined further magnetic parameter with a corresponding predetermined further parameter map of a region around the magnetic sensor to obtain a second estimate of the sensor position, and position determination circuitry configured to weight the first and second estimates of the sensor position according to determined weight information and to determine the sensor position from the weighted first and second estimates. ## Claims ### Claim 1 A position determination device, comprising: a data input circuitry configured to obtain at least one magnetic field vector sensed by a magnetic sensor, a data processor circuitry configured to determine the magnetic magnitude and a further magnetic parameter of the at least one obtained magnetic field vector, a comparison circuitry configured to compare the determined magnetic magnitude with a predetermined magnetic magnitude map of a region around the magnetic sensor to obtain a first estimate of the sensor position and to compare the determined further magnetic parameter with a corresponding predetermined further parameter map of a region around the magnetic sensor to obtain a second estimate of the sensor position, a weight determination circuitry configured to determine weight information indicating the reliability of the first and/or second estimate of the sensor position and/or the relative weight of the first estimate with respect to the second estimate, wherein the weight information is determined based on a local variation of one or more of the magnetic magnitude in the magnetic magnitude map in a local sensor area, wherein the weight of the first estimate is decreased corresponding to less variation in the magnetic magnitude in the local sensor area, and the further magnetic parameter in the further parameter map in the local sensor area, and a position determination circuitry configured to weight the first and second estimates of the sensor position according to the determined weight information and to determine the sensor position from the weighted first and second estimates, wherein a radius range of the local sensor area is adjusted dynamically based on the local variation of one or more of the magnetic magnitude map and the further magnetic parameter map, wherein the radius range is increased corresponding to more variation in the local sensor area. ### Claim 2 (depends on 1) The position determination device as claimed in claim 1, wherein said data processor circuitry is further configured to determine the magnetic inclination, the vertical magnetic component or the horizontal magnetic component of the at least one obtained magnetic field vector as further magnetic parameter. ### Claim 3 (depends on 1) The position determination device as claimed in claim 1, wherein said weight determination circuitry is further configured to determine said weight information based on the variation of the further magnetic parameter, direction of gravity, motion and/or step pattern. ### Claim 4 (depends on 3) The position determination device as claimed in claim 3, wherein said weight determination circuitry is further configured to determine said weight information such that as the weight of the second estimate is increased the fewer variations of the magnetic magnitude, the less motion, and/or the fewer steps are present in a local sensor area. ### Claim 5 (depends on 1) The position determination device as claimed in claim 1, wherein said weight determination circuitry is further configured to determine said weight information such that the weight of the second estimate is increased corresponding to more variation in the further magnetic parameter in the local sensor area. ### Claim 6 (depends on 1) The position determination device as claimed in claim 1, wherein said weight determination circuitry is further configured to determine said local variation in the local sensor area of the magnetic magnitude in the magnetic magnitude map and/or of the further magnetic parameter in the further parameter map from the magnetic magnitude map and/or the further parameter map. ### Claim 7 (depends on 1) The position determination device as claimed in claim 1, wherein said weight determination circuitry is further configured to obtain said local variation as predetermined input. ### Claim 8 (depends on 1) The position determination device as claimed in claim 1, wherein said data input circuitry is further configured to obtain a horizontal magnetic component map and a vertical magnetic component map of the region around the magnetic sensor and said data processor circuitry is further configured to determine said magnetic magnitude map and/or said further parameter map of the region around the magnetic sensor from the obtained horizontal magnetic component map and vertical magnetic component map. ### Claim 9 (depends on 1) The position determination device as claimed in claim 1, wherein said data input circuitry is further configured to obtain said magnetic magnitude map and/or said further parameter map as predetermined input. ### Claim 10 (depends on 1) The position determination device as claimed in claim 1, wherein said weight determination circuitry is further configured to use as local sensor area an area having a radius in a range between 1 m and 20 m. ### Claim 11 (depends on 1) The position determination device as claimed in claim 1, wherein said position determination circuitry is configured to determine a first position likelihood distribution from the first estimate and the weighting information, to determine a second position likelihood distribution from the second estimate and the weighting information, and to determine the sensor position by combining the first and second position likelihood distributions. ### Claim 12 (depends on 1) The position determination device as claimed in claim 1, wherein said comparison circuitry is configured to obtain a first deviation distribution as first estimate, the first deviation distribution indicating the deviation of the determined magnetic magnitude from the magnitude map, and a second deviation distribution as second estimate, the second deviation distribution indicating the deviation of the determined further magnetic parameter from the further parameter map. ### Claim 13 (depends on 1) The position determination device as claimed in claim 1, wherein said comparison circuitry is further configured to use as initial sensor position for determining the region around the magnetic sensor an estimate determined based on the last known position of the magnetic sensor and to reduce the size of the region around the magnetic sensor in subsequent comparison steps. ### Claim 14 (depends on 1) The position determination device as claimed in claim 1, wherein said data input circuitry is further configured to receive motion information and/or orientation information indicating motion and/or orientation of the magnetic sensor and wherein said data processor circuitry is further configured to determine the magnetic inclination of the at least one obtained magnetic field vector as further magnetic parameter and to correct the determined magnetic inclination for rotation of the magnetic sensor based on the obtained motion information. ### Claim 15 A position determination method comprising: obtaining at least one magnetic field vector sensed by a magnetic sensor; determining the magnetic magnitude and a further magnetic parameter of the at least one obtained magnetic field vector; comparing the determined magnetic magnitude with a predetermined magnetic magnitude map of a region around the magnetic sensor to obtain a first estimate of the sensor position; comparing the determined further magnetic parameter with a corresponding predetermined further parameter map of a region around the magnetic sensor to obtain a second estimate of the sensor position; determining weight information indicating the reliability of the first and/or second estimate of the sensor position and/or the relative weight of the first estimate with respect to the second estimate, wherein the weight information is determined based on a local variation of one or more of the magnetic magnitude in the magnetic magnitude map in a local sensor area, wherein the weight of the first estimate is decreased corresponding to less variation in the magnetic magnitude in the local sensor area, and the further magnetic parameter in the further parameter map in the local sensor area; weighting the first and second estimates of the sensor position according to the determined weight information; and determining the sensor position from the weighted first and second estimates, wherein a radius range of the local sensor area is adjusted dynamically based on the local variation of one or more of the magnetic magnitude map and the further magnetic parameter map, wherein the radius range is increased corresponding to more variation in the local sensor area. ### Claim 16 (depends on 1) A mobile device comprising: a magnetic sensor for sensing at least one magnetic field vector at the position of the mobile device; a position determination device as claimed in claim 1 for determining the position of the mobile device based on the at least one magnetic field vector sensed by the magnetic sensor. ### Claim 17 (depends on 16) The mobile device as claimed claim 16, further comprising a motion detector for obtaining motion information indicating motion of the mobile device. ### Claim 18 (depends on 16) The mobile device as claimed claim 16, wherein said mobile device is one of a handheld device, wearable device, mobile phone, smartphone, portable phone, camera, watch, vital signs monitor, laptop, tablet, or glasses. ### Claim 19 A non-transitory computer-readable recording medium that stores therein a computer program product, which, when executed by a processor, causes the processor to perform a method, the method comprising: obtaining at least one magnetic field vector sensed by a magnetic sensor; determining the magnetic magnitude and a further magnetic parameter of the at least one obtained magnetic field vector; comparing the determined magnetic magnitude with a predetermined magnetic magnitude map of a region around the magnetic sensor to obtain a first estimate of the sensor position; comparing the determined further magnetic parameter with a corresponding predetermined further parameter map of a region around the magnetic sensor to obtain a second estimate of the sensor position; determining weight information indicating the reliability of the first and/or second estimate of the sensor position and/or the relative weight of the first estimate with respect to the second estimate, wherein the weight information is determined based on a local variation of one or more of the magnetic magnitude in the magnetic magnitude map in a local sensor area, wherein the weight of the first estimate is decreased corresponding to less variation in the magnetic magnitude in the local sensor area, and the further magnetic parameter in the further parameter map in the local sensor area; weighting the first and second estimates of the sensor position according to the determined weight information; and determining the sensor position from the weighted first and second estimates, wherein a radius range of the local sensor area is adjusted dynamically based on the local variation of one or more of the magnetic magnitude map and the further magnetic parameter map, wherein the radius range is increased corresponding to more variation in the local sensor area.