Method for the continuous real time tracking of the position of at least one mobile object as well as an associated device

• US 7,139,582 B2
• Filed: 10/27/2003
• Issued: 11/21/2006
• Est. Priority Date: 10/28/2002
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer-Gesellschaft ZUR Forderung Der Angewandten Forschung EV
• Inventors: Hofmann, Günter, Koehler, Stefan, Eberlein, Ernst, Retkowski, Reiner, Von Der Grün, Thomas, Couronné, Sylvia, Breiling, Marco, Bliesze, Marcus
• Primary Examiner(s): D AGOSTA, STEPHEN M
• Application Number:
  US10/693,631
• Publication Number:
  US 20040171388A1
• Time in Patent Office: 1,121 Days
• Field of Search: 4554561-457, 455450-453, 455/455, 370/319, 370/320, 370/321, 370/322, 370/324, 370/326, 342/453, 342/457, 342/463
• US Class Current: 455/456.1
• CPC Class Codes: A63B 2024/0025 Tracking the path or location of one or more users, e.g. players of a game
• CPC Class Codes: A63B 2220/836 Sensors arranged on the body of the user
• CPC Class Codes: A63B 2225/50 Wireless data transmission, e.g. by radio transmitters or telemetry
• CPC Class Codes: A63B 2243/0025 Football American football A63B2243/007
• CPC Class Codes: A63B 24/0021 Tracking a path or terminating locations
• CPC Class Codes: A63B 71/0605 Decision makers and devices using detection means facilitating arbitration
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence

Abstract

In a method for the continuous real time tracking of the position of at least one mobile object in a defined multidimensional space, at least one mobile transmitter module is attached to at least one mobile object and the signals from the at least one module are received by a stationary receiving and signal processing network and then centrally processed. The signals emitted by each transmitter module are electromagnetic waves sent within a frequency band range using time division multiplexing techniques. Due to the fact that the frequency band is used as a single channel for the purpose of maximizing the accuracy with which a position is detected, and due also to the fact that the communication process between the transmitters and the receivers is based on the principle of pseudo-random time division multiplexing using burst transmissions of low cross correlation with non synchronized pseudo-random patterns, there is created a method for the continuous tracking of the position of one or more mobile objects at any time and in any place which is of very high positional resolution and has a temporal resolution of just a few milliseconds.

Claims

1. A method for the continuous real time tracking of the position of a plurality of mobile objects in a defined multidimensional space, comprising:

attaching transmitter modules to the mobile objects;

receiving signals from the transmitter modules by a stationary receiving and signal processing network; and

processing the received signals centrally,

wherein the signals emitted by the transmitter modules are electromagnetic waves which are transmitted within a frequency band that is used as a single channel without a feedback channel,

wherein a communication process between the transmitter modules and receivers of the receiving and signal processing network is based on a principle of pseudo-random time division multiplexing using non synchronized pseudo-random patterns, such that each transmitter module emits a characteristic transmission pattern having a sequence of burst transmissions that occur at pseudo-random times,

wherein the burst transmissions are characterized by a low cross correlation, so that there is a low probability of transmitting burst transmissions at the same time, and

wherein the characteristic transmission patterns of the transmitter modules are already known to the receiving and signal processing network, and after each burst transmission from a transmitter module is received by the receivers, the receiving and signal processing network calculates a search range for each receiver during which the next burst transmission of the characteristic transmission pattern of the same transmitter module is expected to arrive, the search range having a duration that is substantially longer than the duration of the burst transmissions.

2. A method in accordance with claim 1, wherein the principle of pseudo-random time division multiplexing comprises a process of transmitting at isolated, irregular time points.

3. A method in accordance with claim 1, wherein the receiving and signal processing network estimates the time point of the next burst transmission from each transmitter module.

4. A method in accordance with claim 1, wherein only those burst transmissions are evaluated by the receiving and signal processing network which arrive at the receivers during the search ranges.

5. A method in accordance with claim 3, wherein the next burst transmission from each transmitter module is determined continuously.

6. A method in accordance with claim 1, wherein the transmitter modules are miniaturized, at least one of the transmitter modules being small enough to be inserted into a ball.

7. A method in accordance with claim 1, wherein the frequency band lies at approximately 2.4 GHz.

8. A method in accordance with claim 1, wherein the frequency band has a bandwidth of about 80 MHz.

9. A method in accordance with claim 1, wherein the receiving and signal processing network comprises stationary reference transmitters that are used as position references for the purposes of minimizing errors and for calibration of the positions of the transmitter modules, said reference transmitters transmitting an identification code in a sequence, the signals from said reference transmitters being detected by the receivers of the receiving and signal processing network for purposes of determining their time of arrival at the respective receivers.

10. A method in accordance with claim 1, wherein the characteristic transmission patterns are a combination of access mechanisms, time division multiplexing, and code division multiplexing.

11. A method in accordance with claim 1, wherein the characteristic transmission patterns are prime number sequences.

12. A method in accordance with claim 1, wherein in the case of the burst transmissions a separation of at least two signals of different origin arriving randomly at the same time is effected by a receiver of the receiving and signal processing network.

13. A method in accordance with claim 1, wherein the burst transmissions are transmitted at a pulse rate which is so high that undetected individual values are tolerated.

14. A method in accordance with claim 1, wherein the receiving and signal processing network comprises means for receiving analog signals, digitizing the received signals, and determining and storing time points, at which the signals from respective transmitter modules are received.

15. A method in accordance with claim 1, wherein different algorithms can be used by the receiving and signal processing network for the processing of received and stored signals in different situations.

16. A method in accordance with claim 15, wherein the receiving and signal processing network comprises means for dividing received signals into sections for processing of the received signals, and the best respective algorithm or a plurality of algorithms are used simultaneously for the individual sections.

17. A method in accordance with claim 15, wherein the receiving and signal processing network comprises means for dividing received signals into sections for processing of the received signals, and a rotated time axis is also used for individual sections so that discontinuities in highly dynamic processes are approached from two sides.

18. A system for transmitting electromagnetic waves for use in a method for continuous real time tracking of the position of mobile objects in a defined multidimensional space, comprising:

a plurality of transmitter modules which are attached to the mobile objects; and

a stationary receiving and signal processing network for receiving and processing signals transmitted by the transmitter modules, said signals being waves which are transmitted in a frequency band that is used as a single channel without a feedback channel,

wherein a communication process between the transmitter modules and receivers of the receiving and signal processing network is based on a principle of pseudo-random time division multiplexing with non synchronized pseudo-random patterns, such that each transmitter module emits a characteristic transmission pattern having a sequence of burst transmissions that occur at pseudo-random times,

wherein the burst transmissions have a low cross correlation, so that there is a low probability of transmitting burst transmissions at the same time, and

wherein the characteristic transmission patterns of the transmission modules is already known to the receiving and signal processing network, and after each burst transmission from a transmitter module is received by the receivers, the receiving and signal processing network calculates a search range for each receiver during which the next burst transmission of the characteristic transmission pattern of the same transmitter module is expected to arrive, the search range having a duration that is substantially longer than the duration of the burst transmissions.

19. A method for the continuous real time tracking of the position of a mobile object, comprising:

attaching a mobile transmitter module to the mobile object;

placing at least one reference transmitter module at at least one known position; and

receiving signals emitted by the transmitter modules with a plurality of receivers of a receiving and signal processing network,

wherein an available frequency band is used as a single channel without a feedback channel;

wherein a communication process between the receivers and the mobile transmitter module is based on a principle of pseudo-random time division multiplexing using non synchronized pseudo-random patterns, such that the mobile transmitter module emits a characteristic transmission pattern having a sequence of burst transmissions that occur at pseudo-random times, and

wherein the characteristic transmission pattern of the mobile transmitter module is already known to the receiving and signal processing network, and after each burst transmission from the mobile transmitter module is received by the receivers, the receiving and signal processing network calculates a search range for each receiver during which the next burst transmission of the characteristic transmission pattern of the mobile transmitter module is expected to arrive, the search range having a duration that is substantially longer than the duration of the burst transmissions.

20. A method for the continuous real time tracking of the position of a mobile object in a defined multidimensional space in which-at least one transmitter module is disposed, comprising:

attaching said at least one transmitter module to the mobile object;

receiving signals from the at least one transmitter module by a stationary receiving and signal processing network; and

processing the received signals centrally,

wherein the signals emitted by the at least one transmitter module are electromagnetic waves which are transmitted within a frequency band that is used as a single channel without a feedback channel,

wherein a communication process between the at least one transmitter module and receivers of the receiving and signal processing network is based on a principle of pseudo-random time division multiplexing using non synchronized pseudo-random patterns, such that each at least one transmitter module emits a characteristic transmission pattern having a sequence of burst transmissions that occur at pseudo-random times,

wherein the burst transmissions are characterized by a low cross correlation, so that there is a low probability of transmitting burst transmissions at the same time, and

wherein the characteristic transmission pattern of the at least one transmitter module is already known to the receiving and signal processing network, and after each burst transmission from a transmitter module is received by the receivers, the receiving and signal processing network calculates a search range for each receiver during which the next burst transmission of the characteristic transmission pattern of the same transmitter module is expected to arrive, the search range having a duration that is substantially longer than the duration of the burst transmissions.

21. A method for the continuous real time tracking of the position of a mobile object in a defined multidimensional space in which a plurality of transmitter modules are disposed, comprising:

attaching one of said transmitter modules to the mobile object;

receiving signals from the transmitter modules by a stationary receiving and signal processing network; and

processing the received signals centrally,

wherein the signals emitted by the transmitter modules are electromagnetic waves which are transmitted within a frequency band that is used as a single channel without a feedback channel,

wherein a communication process between the transmitter modules and receivers of the receiving and signal processing network is based on a principle of pseudo-random time division multiplexing using non synchronized pseudo-random patterns, such that each transmitter emits a characteristic transmission pattern having a sequence of burst transmissions that occur at pseudo-random times,

wherein the burst transmissions are characterized by a low cross correlation, so that there is a low probability of transmitting burst transmissions at the same time, and

wherein the characteristic transmission patterns of the transmitter modules is already known to the receiving and signal processing network, and after each burst transmission from a transmitter module is received by the receivers, the receiving and signal processing network calculates a search range for each receiver during which the next burst transmission of the characteristic transmission pattern of the same transmitter module is expected to arrive, the search range having a duration that is substantially longer than the duration of the burst transmissions.