Real-time method and system for determining and validating location of a relocated mobile object or person in a tracking environment

1. A real-time method of determining and validating location of a relocated mobile object or person in a tracking environment in which a plurality of sensors are located, the method comprising:

(a) providing a tracking tag having storage and wearable by the person or attachable to the object;

(b) storing a set of data related to a prior location of a relocated tag in the tracking environment in the storage;

(c) modulating a first carrier signal with a first packet including a first set of data to obtain a modulated first signal;

(d) transmitting from the tag to a sensor nearest the relocated tag the first signal, the first signal containing the first packet and having a first precision and a first range within the environment;

(e) receiving a modulated second signal at the tag from at least one of the sensors including the nearest sensor, the second signal containing a second packet including a second set of data and having a second precision and a second range within the environment;

(f) demodulating the second signal to obtain the second packet;

(g) repeating steps (c) through (f) if the second set of data is different from the stored set of data to obtain a plurality of second packets; and

(h) determining and validating current location of the relocated tag within the environment based on the plurality of second packets.

2. The method as claimed in claim 1 wherein at least a portion of the second set of data uniquely identifies the nearest sensor.

3. The method as claimed in claim 1 wherein the first set of data non-uniquely identifies the tag.

4. The method as claimed in claim 1 wherein the first set of data uniquely identifies the tag.

5. The method as claimed in claim 1 wherein the first packet is an IR packet.

6. The method as claimed in claim 1 wherein the second packet is an RF packet.

7. The method as claimed in claim 1 wherein the tracking environment is a clinical environment.

8. The method as claimed in claim 1 further comprising:

storing the at least a portion of one of the second sets of data in the tag to obtain stored data;

modulating a third carrier signal with a third packet including the stored data to obtain a modulated third signal; and

transmitting from the tag to a device other than the nearest sensor the third signal, the third signal having a third precision and a third range within the environment.

9. The method as claimed in claim 1 wherein the tag is a multi-modal tag.

10. The method as claimed in claim 1 wherein the first precision is greater than the second precision and the first range is shorter than the second range.

11. The method as claimed in claim 8 wherein the third packet is an RF packet.

12. The method as claimed in claim 8 wherein the first precision is greater than the third precision and the first range is shorter than the third range.

13. The method as claimed in claim 1 wherein the first and second signals are electromagnetic signals.

14. The method as claimed in claim 13 wherein the first signal is an IR signal and the second signal is an RF signal.

15. The method as claimed in claim 1 wherein the first signal is a line-of-sight signal and the second signal is a non-line-of-sight signal.

16. The method as claimed in claim 8 wherein the first, second and third signals are electromagnetic signals.

17. The method as claimed in claim 16 wherein the first signal is an IR signal and the second and third signals are RF signals.

18. The method as claimed in claim 8 wherein the first signal is a line-of-sight signal and the second and third signals are non-line-of-sight signals.

19. The method as claimed in claim 1 wherein the tag is battery-operated.

20. The method as claimed in claim 1 wherein the nearest sensor is battery-operated.

21. A real-time system of determining and validating location of a relocated mobile object or person in a tracking environment, the system comprising:

a plurality of sensors located in the tracking environment; and

a tracking tag wearable by the person or attachable to the object, the tag having storage and being programmed to at least partially perform the steps of:

(a) storing a set of data related to a prior location of the relocated tag in the tracking environment in the storage;

(b) modulating a first carrier signal with a first packet including a first set of data to obtain a modulated first signal;

(c) transmitting to a sensor nearest the relocated tag the first signal, the first signal containing the first packet and having a first precision and a first range within the environment;

(d) receiving a modulated second signal from at least one of the sensors including the nearest sensor, the second signal containing a second packet including a second set of data and having a second precision and a second range within the environment;

(e) demodulating the second signal to obtain the second packet;

(f) repeating steps (b) through (e) if the second set of data is different from the stored set of data to obtain a plurality of second packets; and

(g) determining and validating current location of the relocated tag within the environment based on the plurality of second packets.

22. The system as claimed in claim 21 wherein at least a portion of the second set of data uniquely identifies the nearest sensor.

23. The system as claimed in claim 21 wherein the first set of data non-uniquely identifies the tag.

24. The system as claimed in claim 21 wherein the first set of data uniquely identifies the tag.

25. The system as claimed in claim 21 wherein the first packet is an IR packet.

26. The system as claimed in claim 21 wherein the second packet is an RF packet.

27. The system as claimed in claim 21 wherein the tracking environment is a clinical environment.

28. The system as claimed in claim 21 wherein the tag is further programmed to at least partially perform the steps of:

storing the at least a portion of one of the second sets of data in the tag to obtain stored data;

modulating a third carrier signal with a third packet including the stored data to obtain a modulated third signal; and

transmitting to a device other than the nearest sensor the third signal, the third signal having a third precision and a third range within the environment.

29. The system as claimed in claim 21 wherein the tag is a multi-modal tag.

30. The system as claimed in claim 21 wherein the first precision is greater than the second precision and the first range is shorter than the second range.

31. The system as claimed in claim 28 wherein the third packet is an RF packet.

32. The system as claimed in claim 28 wherein the first precision is greater than the third precision and the first range is shorter than the third range.

33. The system as claimed in claim 21 wherein the first and second signals are electromagnetic signals.

34. The system as claimed in claim 33 wherein the first signal is an IR signal and the second signal is an RF signal.

35. The system as claimed in claim 21 wherein the first signal is a line-of-sight signal and the second signal is a non-line-of-sight signal.

36. The system as claimed in claim 28 wherein the first, second and third signals are electromagnetic signals.

37. The system as claimed in claim 36 wherein the first signal is an IR signal and the second and third signals are RF signals.

38. The system as claimed in claim 28 wherein the first signal is a line-of-sight signal and the second and third signals are non-line-of-sight signals.

39. The system as claimed in claim 21 wherein the tag is battery-operated.

40. The system as claimed in claim 21 wherein the nearest sensor is battery-operated.