# US 11,079,469 B2 · Ultrasonic locationing system using a doubly symmetrical transmission sequence > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,469 B2 - Document ID: US11079469B2 - Status: Granted - Kind: B2 - Application number: 15/591,272 - Filed: 2017-05-10 - Published: 2018-11-15 - Granted: 2021-08-03 - Earliest claimed: 2017-05-10 - Assignees: Symbol Technologies, Inc. - Applicants: Symbol Technologies, LLC - Inventors: Russell Calvarese; Richard J. Lavery; Dammika Prasad Wijethunga - Web page: https://patentgrep.com/patent/US11079469B2 ## CPC - G01S 1/753: {Signal details} - G01S 5/30: Determining absolute distances from a plurality of spaced points of known location - G01S 1/74: Details - G01S 1/751: {Mounting or deployment thereof} - G01S 1/76: Systems for determining direction or position line - G01S 5/0036: {of measured values, i.e. measurement on mobile and position calculation on base station} - G01S 5/18: using ultrasonic, sonic or infrasonic waves - G01S 2201/02: Indoor positioning, e.g. in covered car-parks, mining facilities, warehouses - 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 ## Abstract A method and apparatus for locating a target in a venue is described. A backend controller activates transmitters in a venue to send burst signals using a double symmetry configuration formed of a plurality of separate transmitter groups. The backend controller activates the transmitters into a second, different configuration for bursting. The resulting location signal information from each configuration is obtained by the backend controller, which then more accurately determines the location of the target in the venue. ## Claims ### Claim 1 A system for locating a target in a venue, the system comprising: a plurality of ultrasonic transmitters positioned within the venue according to a physical layout, each transmitter in the plurality of ultrasonic transmitters being configured to transmit ultrasonic ranging pulses in the venue for receipt by the target; and a backend controller, comprising a processor and a memory, the backend controller communicatively coupled to the plurality of ultrasonic transmitters, the backend controller being configured to activate the transmitters in a symmetry mode that comprises a plurality of symmetry transmitter groups, the transmitters in each symmetry transmitter group having a symmetry about a plurality of symmetry lines in the venue, the backend controller being configured to control each symmetry transmitter group to send a respective ranging pulse during a symmetry mode timeframe, the backend controller being further configured to receive location signal information during each of the symmetry mode timeframe of the symmetry mode, and the backend controller being further configured to determine, in response to the location signal information received during the symmetry mode, the location of the target in the venue. ### Claim 2 (depends on 1) The system of claim 1, wherein the backend controller is further configured to: activate the transmitters in a sub-room mode that comprises a plurality of sub-room transmitter groups different than the plurality of symmetry transmitter groups, the backend controller being configured to control each sub-room transmitter group to send a respective ranging pulse during a sub-room mode timeframe, the backend controller being further configured to receive location signal information during each of the sub-room mode timeframe, and the backend controller being further configured to determine, in response to the location signal information received during the symmetry mode and the location signal information received during the sub-room mode, the location of the target in the venue. ### Claim 3 (depends on 2) The system of claim 2, wherein the backend controller is configured to receive the location signal information received during the symmetry mode and the location signal information received during the sub-room mode from the target. ### Claim 4 (depends on 3) The system of claim 3, wherein the location signal information received during the symmetry mode and the location signal information received during the sub-room mode is timestamp data from the target. ### Claim 5 (depends on 1) The system of claim 1, wherein the symmetry mode is a double symmetry mode such that each symmetry transmitter group has symmetry about two orthogonal axes. ### Claim 6 (depends on 5) The system of claim 5, wherein the two orthogonal axes are a horizontal axis in the venue and a vertical axis in the venue. ### Claim 7 (depends on 5) The system of claim 5, wherein the double symmetry mode is defined by a plurality of repeating geometric cells. ### Claim 8 (depends on 7) The system of claim 7, wherein the repeating geometric cells are repeating rectangular shaped cells, square-shaped cells or repeating diamond-shaped cells. ### Claim 9 A method of locating a target in a venue having a plurality of ultrasonic transmitters positioned within the venue, the method comprising: activating, using a backend controller communicatively coupled to the plurality of ultrasonic transmitters, the plurality of ultrasonic transmitters in a symmetry mode that comprises a plurality of symmetry transmitter groups, the transmitters in each symmetry transmitter group having a symmetry about a plurality of symmetry lines in the venue, transmitting, using the plurality of ultrasonic transmitters activated in the symmetry mode, ultrasonic ranging pulses in the venue during a symmetry mode timeframe; receiving location signal information during each of the symmetry mode timeframe; and determining, in response to the location signal information received during the symmetry mode, the location of the target in the venue. ### Claim 10 (depends on 9) The method of claim 9, further comprising: activating, using the backend controller, the transmitters in a sub-room mode that comprises a plurality of sub-room transmitter groups different than the plurality of symmetry transmitter groups; transmitting, using the plurality of ultrasonic transmitters activated in the sub-room mode, ultrasonic ranging pulses in the venue during a sub-room mode timeframe; receiving location signal information during each of the sub-room mode timeframe; and determining, in response to the location signal information received during the symmetry mode and the location signal information received during the sub-room mode, the location of the target in the venue. ### Claim 11 (depends on 10) The method of claim 10, further comprising: receiving, at the backend controller, the location signal information received during the symmetry mode from the target; and receiving, at the backend controller, the location signal information received during the sub-room mode from the target. ### Claim 12 (depends on 11) The method of claim 11, wherein the location signal information received during the symmetry mode and the location signal information received during the sub-room mode is timestamp data from the target. ### Claim 13 (depends on 9) The method of claim 9, wherein the symmetry mode is a double symmetry mode such that each symmetry transmitter group has symmetry about two orthogonal axes. ### Claim 14 (depends on 13) The method of claim 13, wherein the two orthogonal axes are a horizontal axis in the venue and a vertical axis in the venue. ### Claim 15 (depends on 13) The method of claim 13, wherein the double symmetry mode is defined by a plurality of repeating geometric cells. ### Claim 16 (depends on 15) The method of claim 15, wherein the repeating geometric cells are repeating rectangular shaped cells, square-shaped cells or repeating diamond-shaped cells. ### Claim 17 An ultrasonic locationing system for locating a target in a venue, the system comprising: a plurality of ultrasonic transmitters positioned within the venue, each transmitter being configured to transmit ultrasonic ranging pulses in the venue for receipt by the target; and a backend controller, comprising at least one processor and at least one memory, the backend controller communicatively coupled to the plurality of transmitters, the backend controller being configured to actuate the transmitters in different transmitter groups for sending ultrasonic ranging pulses, each transmitter group exhibiting symmetry about one or more symmetry lines in the venue, the backend controller being further configured to actuate each transmitter group in a sequential order each over a respective timeframe, and the backend controller being configured to receive location signal information during each of the timeframe and to determine a location of the target in the venue from the received location signal information obtained from the plurality of transmitter groups.