# US 12,111,981 B2 · Method and system utilizing phased array beamforming for six degree of freedom tracking for an emitter in augmented reality systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,111,981 B2 - Document ID: US12111981B2 - Status: Granted - Kind: B2 - Application number: 18/212,645 - Filed: 2023-06-21 - Published: 2023-10-19 - Granted: 2024-10-08 - Earliest claimed: 2019-02-28 - Assignees: Magic Leap, Inc. - Applicants: Magic Leap, Inc. - Inventors: Michael Janusz Woods - Web page: https://patentgrep.com/patent/US12111981B2 ## CPC - A63F 13/21: characterised by their sensors, purposes or types - G06F 3/0346: with detection of the device orientation or free movement in a three-dimensional [3D] space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors - A63F 13/235: using a wireless connection, e.g. infrared or piconet - A63F 13/24: Constructional details thereof, e.g. game controllers with detachable joystick handles - A63F 13/428: involving motion or position input signals, e.g. signals representing the rotation of an input controller or a player's arm motions sensed by accelerometers or gyroscopes - A63F 13/92: Video game devices specially adapted to be hand-held while playing - G01S 13/02: Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems - G01S 13/426: {Scanning radar, e.g. 3D radar (G01S13/66 takes precedence)} - G01S 13/88: Radar or analogous systems specially adapted for specific applications (electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00) - G02B 27/0087: {Phased arrays} - G02B 27/0093: {with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking} - G02B 27/017: {Head mounted} - G06F 3/011: {Arrangements for interaction with the human body, e.g. for user immersion in virtual reality (blind teaching G09B21/00)} - G06F 3/012: {Head tracking input arrangements} - G06F 3/016: {Input arrangements with force or tactile feedback as computer generated output to the user} - G01S 2013/0245: {Radar with phased array antenna} - G02B 2027/0187: {slaved to motion of at least a part of the body of the user, e.g. head, eye} - A63F: CARD, BOARD, OR ROULETTE GAMES; INDOOR GAMES USING SMALL MOVING PLAYING BODIES; VIDEO GAMES; GAMES NOT OTHERWISE PROVIDED FOR - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An electromagnetic tracking system includes a handheld controller including a first phased array element characterized by a first phase and a second phased array element characterized by a second phase different than the first phase. The first phased array element and the second phased array element are configured to generate a steerable electromagnetic beam characterized by an electromagnetic field pattern. The electromagnetic tracking system also includes a head mounted augmented reality display including an electromagnetic sensor configured to sense the electromagnetic field pattern. ## Claims ### Claim 1 An electromagnetic tracking system comprising: a handheld controller including an electromagnetic emitter, the electromagnetic emitter including: a first phased array element characterized by a first phase; and a second phased array element characterized by a second phase different than the first phase wherein the first phased array element and the second phased array element are configured to generate a steerable electromagnetic beam characterized by an electromagnetic field pattern; and a head mounted display including an electromagnetic sensor configured to sense the electromagnetic field pattern; wherein the electromagnetic tracking system is configured to: control the first phase and the second phase to steer the electromagnetic beam to increase received power at the electromagnetic sensor; and determine a pose of the handheld controller relative to the electromagnetic sensor using the electromagnetic field pattern sensed at the electromagnetic sensor. ### Claim 2 (depends on 1) The electromagnetic tracking system of claim 1, wherein the electromagnetic tracking system is further configured to: digitally compute a position and orientation of the handheld controller based on the electromagnetic field pattern. ### Claim 3 (depends on 1) The electromagnetic tracking system of claim 1, further comprising an auxiliary unit including the handheld controller. ### Claim 4 (depends on 3) The electromagnetic tracking system of claim 3, wherein the auxiliary unit comprises a belt pack. ### Claim 5 (depends on 1) The electromagnetic tracking system of claim 1, wherein the head mounted display is a head mounted virtual reality (VR) display. ### Claim 6 (depends on 1) The electromagnetic tracking system of claim 1, wherein the head mounted display is a head mounted augmented reality (AR) display. ### Claim 7 (depends on 1) The electromagnetic tracking system of claim 1, wherein the electromagnetic emitter further comprises a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane. ### Claim 8 (depends on 7) The electromagnetic tracking system of claim 7, wherein the electromagnetic emitter further comprises a fourth phased array element, wherein the first phased array element, the second phased array element, and the third phased array element form three corners of a tetrahedron and the fourth phased array element forms a fourth corner of the tetrahedron. ### Claim 9 A method of determining a six degree of freedom (DoF) pose of a handheld controller, the method comprising: generating an electromagnetic beam from the handheld controller, wherein the electromagnetic beam is characterized by an electromagnetic field pattern; steering the electromagnetic beam to increase received power at a electromagnetic sensor; determining a beam angle associated with the electromagnetic beam; determining a distance between the handheld controller and the electromagnetic sensor; and determining the six DoF pose of the handheld controller relative to the electromagnetic sensor using the beam angle and the distance. ### Claim 10 (depends on 9) The method of claim 9, wherein the handheld controller includes an electromagnetic emitter, the electromagnetic emitter including: a first phased array element configured to operate with a first phase; and a second phased array element configured to operate with a second phase. ### Claim 11 (depends on 10) The method of claim 10, wherein the electromagnetic emitter further includes a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane. ### Claim 12 (depends on 9) The method of claim 9, wherein the electromagnetic sensor is an element of a headset. ### Claim 13 (depends on 9) The method of claim 9, wherein steering the electromagnetic beam comprises aligning a central vector of the electromagnetic beam with a vector from the handheld controller to the electromagnetic sensor. ### Claim 14 (depends on 9) The method of claim 9, wherein steering the electromagnetic beam to increase received power at the electromagnetic sensor comprises maximizing received power at the electromagnetic sensor. ### Claim 15 A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising: generating an electromagnetic beam from a handheld controller, wherein the electromagnetic beam is characterized by an electromagnetic field pattern; steering the electromagnetic beam to increase received power at a electromagnetic sensor; determining a beam angle associated with the electromagnetic beam; determining a distance between the handheld controller and the electromagnetic sensor; and determining a six degree of freedom (DoF) pose of the handheld controller relative to the electromagnetic sensor using the beam angle and the distance. ### Claim 16 (depends on 15) The non-transitory computer-readable medium of claim 15, wherein the handheld controller includes an electromagnetic emitter, the electromagnetic emitter including: a first phased array element configured to operate with a first phase; and a second phased array element configured to operate with a second phase. ### Claim 17 (depends on 16) The non-transitory computer-readable medium of claim 16, wherein the electromagnetic emitter further includes a third phased array element, wherein the first phased array element, the second phased array element, and the third phased array element are disposed in a plane. ### Claim 18 (depends on 15) The non-transitory computer-readable medium of claim 15, wherein the electromagnetic sensor is an element of a headset. ### Claim 19 (depends on 15) The non-transitory computer-readable medium of claim 15, wherein steering the electromagnetic beam comprises aligning a central vector of the electromagnetic beam with a vector from the handheld controller to the electromagnetic sensor. ### Claim 20 (depends on 15) The non-transitory computer-readable medium of claim 15, wherein steering the electromagnetic beam to increase received power at the electromagnetic sensor comprises maximizing received power at the electromagnetic sensor.