Acoustical system and method for simultaneously locating and tracking multiple personnel in rooms of a building

• US 6,292,106 B1
• Filed: 10/13/1998
• Issued: 09/18/2001
• Est. Priority Date: 10/13/1998
• Status: Expired due to Term

• Current Assignee: Cubic Defense Systems, Inc. (Cubic Corporation)
• Original Assignee: Cubic Defense Systems, Inc. (Cubic Corporation)
• Inventors: Solinsky, James C., Roes, John B.
• Primary Examiner(s): Zimmerman, Brian
• Assistant Examiner(s): Dalencourt, Yves
• Application Number:
  US09/170,584
• Time in Patent Office: 1,071 Days
• Field of Search: 340/825.49, 340/10.2, 340/10.6, 340/573.4, 367/124, 367/199, 367/99, 342/353, 342/450, 701/213, 701/215
• US Class Current: 340/8.1
• CPC Class Codes: G01S 11/16 using difference in transit time between electrical and acoustic signals
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G01S 5/30 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: G08B 3/1083 Pager locating systems

Abstract

A radio frequency (RF) sync pulse is transmitted throughout a building having a plurality of rooms to be traversed by a plurality of players during, for example, an assault training exercise. Ultra-sound pulses are transmitted from fixed piezoelectric transducers mounted at each corner of each room. The ultra-sound pulses with encoded room identity information are generated in a predetermined timed sequence by different ultra-sound transducers after each RF sync pulse. Each player carries an RF receiver for receiving the RF sync pulses. Each player also carries multiple microphones for receiving the ultra-sound pulses transmitted in a room in which the player is currently located. Timing circuitry carried by each player generates signals representative of the delays between each RF sync pulse and the receipt of each of the ultra-sound pulses sequentially received thereafter. Each player carries an RF transmitter for transmitting an RF tracking signal representing an identity of the room an identity of the player and the respective delays that each ultra-sound pulse is received after each RF sync pulse. A control facility receives all of the RF tracking signals from all of the players and determines each player'"'"'s current position within one of the rooms based upon the room identity code and the delays that each ultra-sound pulse is received after each RF sync pulse for each player. The control facility displays the identity and current location of each player as each player moves within the rooms and moves from room to room. The azimuth and elevation of each player along with the articulation of a weapon held by each player can also be determined and displayed.

Claims

1. A system for locating and tracking personnel in rooms of a building, comprising:

means for transmitting a radio frequency (RF) sync pulse throughout a building having a plurality of rooms to be traversed by a plurality of players;

means for transmitting ultra-sound pulses from a plurality of fixed locations in each room, the ultra-sound pulses being generated in a predetermined timed sequence after each RF sync pulse;

means on each player for receiving the RF sync pulses and generating signals representative of the time each RF pulse is received;

means on each player for receiving the ultra-sound pulses transmitted in a room in which the player is currently located and generating signals representative of the delays between each RF sync pulse and the receipt of each of the ultra-sound pulses sequentially received thereafter;

means on each player for transmitting an RF tracking signal representing an identity of the player and the delays that each ultra-sound pulse is received after each RF sync pulse; and

control facility means for receiving the RF tracking signals from the players and for determining each player'"'"'s current position within one of the rooms based upon the delays that each ultra-sound pulse is received after each RF sync pulse for each player and for displaying the identity and current location of each player as each player moves within the rooms and moves from room to room.

2. The system of claim 1 wherein the ultra-sound pulses transmitted in each room are modulated in a manner indicative of a unique identity of that room, the RF tracking signal also represents the identity of the room in which the player is currently located and the control facility means displays the identity of the room in which the player is currently located.

3. The system of claim 1 wherein the means for transmitting ultra-sound pulses from a plurality of fixed locations in each room includes a piezoelectric ultra-sound transducer mounted in each one of a plurality of corners of the room.

4. The system of claim 1 wherein the means on each player for receiving the ultra-sound pulses includes at least one microphone.

5. The system of claim 1 wherein the control facility means further determines and displays an azimuth of each player.

6. The system of claim 1 wherein the control facility means further determines and displays an elevation of each player.

7. The system of claim 1 wherein the control facility means further determines an articulation of a weapon held by each player.

8. The system of claim 1 wherein the control facility means displays the current location of each player in real time.

9. The system of claim 1 wherein the control facility means includes means for compensating for changes in temperature and/or humidity to minimize degradation in location accuracy.

10. The system of claim 3 wherein the means for transmitting ultra-sound pulses further includes means for generating a pulse of predetermined amplitude and duration sufficient to cause each piezoelectric ultra-sound transducer to resonate.

11. A method for locating and tracking personnel in rooms of a building, comprising:

transmitting a radio frequency (RF) sync pulse throughout a building having a plurality of rooms to be traversed by a plurality of players;

transmitting ultra-sound pulses from a plurality of fixed locations in each room, the ultra-sound pulses being generated in a predetermined timed sequence after each RF sync pulse;

receiving at each player the RF sync pulses and generating signals representative of the time each RF pulse is received by each player;

receiving at each player the ultra-sound pulses transmitted in a room in which the player is currently located and generating signals representative of the delays between each RF sync pulse and the receipt of each of the ultra-sound pulses sequentially received thereafter by each player;

transmitting from each player an RF tracking signal representing an identity of the player and the delays that each ultra-sound pulse is received after each RF sync pulse by the player;

receiving the RF tracking signals from all the players and determining each player'"'"'s current position within one of the rooms based upon the delays that each ultra-sound pulse is received after each RF sync pulse for each player; and

displaying the identity and current location of each player as the player moves within the rooms.

12. The method of claim 11 wherein the ultra-sound pulses transmitted in each room are modulated in a manner indicative of a unique identity of that room, the RF tracking signal also represents the identity of the room in which the player is currently located.

13. The method of claim 11 wherein the ultra-sound pulses are transmitted from a plurality of fixed locations in each room includes a ceramic ultra-sound transducer mounted in a corresponding corner of the room.

14. The method of claim 11 wherein each player receives the ultra-sound pulses with at least one microphone.

15. The method of claim 11 and further comprising the step of determining and displaying an azimuth and/or an elevation of each player.

16. The method of claim 11 wherein the ultra-sound pulses are generated by energizing a transducer with a high voltage pulse of very short duration to thereby cause the transducer to resonate at a predetermined desired frequency.

17. The method of claim 11 and further comprising the step of determining and displaying an articulation of a weapon held by each player.

18. The method of claim 11 and further comprising the step of compensating for changes in temperature and/or humidity to minimize degradation in location accuracy.

19. The method of claim 16 wherein the transducer is a piezoelectric transducer.

20. A method for locating and tracking multiple personnel in a room of a building, comprising:

transmitting a radio frequency (RF) sync pulse at a first predetermined interval in a room to be traversed by a plurality of players;

transmitting ultra-sound pulses from a plurality of fixed locations in the room, the ultra-sound pulses being generated at second predetermined intervals after each RF sync pulse;

receiving at each player the RF sync pulses and generating a signal representative of the time each RF pulse is received by each player;

receiving at each player the ultra-sound pulses transmitted in the room and generating signals representative of the delays between each RF sync pulse and the receipt of each of the ultra-sound pulses sequentially received thereafter by each player;

transmitting from each player an RF tracking signal representing an identity of the player and the delays that each ultra-sound pulse is received after each RF sync pulse by the player;

receiving the RF tracking signals from all the players and determining each player'"'"'s current position within the room based upon the delays that each ultra-sound pulse is received after each RF sync pulse for each player; and

indicating the identity and current location of each player in the room.