FREQUENCY CHANNEL DIVERSITY FOR REAL-TIME LOCATING SYSTEMS, METHODS, AND COMPUTER PROGRAM PRODUCTS

• US 20120013509A1
• Filed: 07/14/2010
• Published: 01/19/2012
• Est. Priority Date: 07/14/2010
• Status: Active Grant

• Current Assignee: Zebra Technologies Corporation
• Original Assignee: Zebra Enterprise Solutions Corp. (Zebra Technologies Corporation)
• Inventors: Wisherd, David S., O'Hagan, James J.
• Granted Patent: US 8,786,495 B2
• Time in Patent Office: Days
• US Class Current: 342/451
• CPC Class Codes: G01S 1/08 Systems for determining direction or position line
• CPC Class Codes: G01S 5/02213 Receivers arranged in a network for determining the position of a transmitter
• CPC Class Codes: G01S 5/0226 Transmitters
• 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

Provided are architectures, systems, methods, and computer program products for real-time object locating and position determination using frequency channel diversity for transmitting and receiving position determination signals including bursts of location signals. Channelized frequency diversity of a short burst of small location signals that “hop” across multiple frequency channels is used to collectively produce a quasi-wideband position determination signal. Object tags operating with frequency channel diversity for transmitting location signals of position determination signals require low power consumption, but can still efficiently provide adequate position determination signals for reliable position determination.

Claims

1. A method comprising determining, by a computer, a position of an object based upon data, transmitted from a plurality of receivers to the computer, for a plurality of separate wireless location signals individually transmitted over multiple frequency channels by the object and received by the plurality of receivers.

2. The method of claim 1, wherein the multiple frequency channels are selected from a predetermined set of available frequency channels.

3. The method of claim 2, wherein the plurality of separate wireless location signals are transmitted over a consecutive series of frequency channels within the predetermined set of available frequency channels.

4. The method of claim 1, wherein determining the position of the object comprises correlating data from at least two of the plurality of receivers for at least one of the separate wireless location signals transmitted over one of the frequency channels.

5. The method of claim 1, wherein determining the position of the object comprises correlating data from a first one of the plurality of receivers for a first one of the separate wireless location signals transmitted over a first one of the frequency channels and data from a second one of the plurality of receivers for a second one of the separate wireless location signals transmitted over a second one of the frequency channels.

6. The method of claim 1, wherein determining the position of the object comprises discarding data for each of the separate wireless location signals that is not transmitted from at least three of the plurality of receivers.

7. The method of claim 1, wherein determining the position of the object comprises discarding data determined to be outside of an acceptable range of values.

8. The method of claim 7, wherein the acceptable range of values is determined based upon the data from the plurality of receivers.

9. The method of claim 1, further comprising compiling, by the computer, a data load partitioned between two or more of the separate wireless location signals.

10. A computer program product comprising a non-transitory computer-useable storage medium having control logic stored therein for effectuating position determination by a computer, the control logic comprising:

a first code configured to determine a position of an object based upon data, transmitted from a plurality of receivers to the computer, for a plurality of separate wireless location signals individually transmitted over multiple frequency channels by the object and received by the plurality of receivers.

11. The computer program product of claim 10, wherein the first code is further configured to correlate data from at least two of the plurality of receivers for at least one of the separate wireless location signals transmitted over one of the frequency channels.

12. The computer program product of claim 10, wherein the first code is further configured to correlate data from a first one of the plurality of receivers for a first one of the separate wireless location signals transmitted over a first one of the frequency channels and data from a second one of the plurality of receivers for a second one of the separate wireless location signals transmitted over a second one of the frequency channels.

13. The computer program product of claim 10, wherein the first code is further configured to discard data for each of the separate wireless location signals that is not transmitted from at least three of the plurality of receivers.

14. The computer program product of claim 10, wherein the first code is further configured to discard data determined to be outside of an acceptable range of values.

15. The computer program product of claim 10, wherein the first code is further configured to compile a data load partitioned between two or more of the separate wireless location signals.

16. A wireless tag, comprising:

a controller configured to generate a plurality of location signals for collective individual transmission over multiple frequency channels of a predetermined set of available frequency channels; and

a wireless transmitter configured to individually transmit the plurality of location signals over the multiple frequency channels, wherein the controller causes the wireless transmitter to individually transmit at least two of the plurality of location signals over at least two of the predetermined set of available frequency channels.

17. The wireless tag of claim 16, wherein the controller is configured to determine if one of the predetermined set of available frequency channels is in use and, when that frequency channel is in use, to at least temporarily exclude that frequency channel from the multiple frequency channels used to transmit the plurality of location signals.

18. The wireless tag of claim 16, wherein the controller is configured to embed a data load in at least one of the plurality of location signals.

19. The wireless tag of claim 16, wherein the controller is configured to partition a data load between two or more of the plurality of location signals.

20. The wireless tag of claim 19, wherein the controller is configured to evenly distribute the data load amongst the partitions.

21. The wireless tag of claim 19, wherein the controller is configured to partition the data load between fewer of the plurality of location signals than the number of frequency channels of the predetermined set of available frequency channels.

22. The wireless tag of claim 16, wherein the controller is configured to cause the wireless transmitter to transmit the location signals over at least two consecutive frequency channels of the predetermined set of available frequency channels.

23. The wireless tag of claim 16, wherein the predetermined set of available frequency channels comprises sixteen channels, and wherein the wireless transmitter is configured to transmit the location signals over the sixteen channels.

24. The wireless tag of claim 16, wherein each of the frequency channels of the predetermined set of available frequency channels is a 5 MHz channel, and wherein the wireless transmitter is configured to transmit the location signals over the 5 MHz channels.

25. The wireless tag of claim 16, wherein the controller is further configured to adjust the time duration of the transmission of the plurality of location signals based on movement information.

26. A method, comprising:

generating a plurality of location signals for collective individual transmission over at least two frequency channels of a predetermined set of available frequency channels; and

wirelessly transmitting, by a wireless transmitter, the location signals over the at least two frequency channels.

27. The method of claim 26, further comprising determining if one of the predetermined set of available frequency channels is in use and, when that frequency channel is in use, at least temporarily excluding that frequency channel from the available frequency channels to transmit the plurality of location signals.

28. The method of claim 26, further comprising partitioning a data load between two or more of the plurality of location signals.

29. The method of claim 28, further comprising evenly distributing the data load amongst the partitions.

30. The method of claim 28, further comprising partitioning the data load between fewer of the plurality of location signals than the number of frequency channels of the predetermined set of available frequency channels.

31. The method of claim 26, further comprising transmitting the location signals over at least two consecutive frequency channels of the predetermined set of available frequency channels.

32. The method of claim 26, further comprising adjusting the time duration of wirelessly transmitting the location signals based on movement information.

33. A receiver, comprising:

a wireless receiver configured to receive a plurality of location signals transmitted over multiple frequency channels;

a controller configured to determine location data of each of the plurality of location signals; and

a transmitter configured to transmit the location data of the plurality of location signals to a central computer.

34. The receiver of claim 33, wherein the controller is configured to discard location signals of the plurality of location signals determined to be outside of an acceptable range of values.

35. The receiver of claim 34, wherein the acceptable range of values is determined by the controller based upon the plurality of location signals.

36. The receiver of claim 33, wherein the controller is configured to compile a data load partitioned between the data of two or more of the plurality of location signals, and wherein the transmitter is further configured to transmit the data load.

37. The receiver of claim 33, further comprising a timer configured to measure an arrival time of each of the plurality of location signals, wherein the controller is further configured to associate each of the plurality of location signals with the corresponding arrival time of each respective one of the plurality of location signals, thereby defining the location data, and wherein the transmitter is further configured to transmit the arrival time with each of the plurality of location signals to the central computer.

38. The receiver of claim 33, further comprising a timer configured to measure an arrival time of at least one of the plurality of location signals, wherein the controller is further configured to determine the time differences of arrival to each other of the plurality of location signals, thereby defining the location data, and wherein the transmitter is further configured to transmit the time of arrival of at least one of the plurality of location signals and the time differences of arrival to each other of the plurality of location signals to the central computer.

39. A method, comprising:

receiving, by a wireless receiver, a plurality of location signals transmitted over multiple frequency channels;

determining, by a controller, location data of the plurality of location signals; and

transmitting, by a transmitter, the location data of the plurality of location signals to a central computer.

40. The method of claim 39, further comprising determining, by the controller, if one of the location signals of the plurality of location signals is outside of an acceptable range of values and, when that location signal is outside of the acceptable range of values, discarding that location signal.

41. The method of claim 40, further comprising calculating, by the controller, the acceptable range of values based upon the plurality of location signals.

42. The method of claim 39, further comprising

compiling, by the controller, a data load partitioned between two or more of the plurality of location signals;

and

transmitting, by the transmitter, the data load to the central computer.

43. The method of claim 39, further comprising:

measuring, by a timer, an arrival time of each of the plurality of location signals;

associating, by the controller, each of the plurality of location signals with the corresponding arrival time of each respective one of the plurality of location signals; and

transmitting the arrival time with each of the plurality of location signals to the central computer.

44. The method of claim 39, further comprising:

measuring, by a timer, an arrival time of each of the plurality of location signals;

determining, by the controller, the time differences of arrival between each of the plurality of location signals; and

transmitting the time of arrival of at least one of the plurality of location signals and the time differences of arrival between each of the plurality of location signals to the central computer.