Systems and methods for geographic positioning using radio spectrum signatures

• US 20060125692A1
• Filed: 12/13/2004
• Published: 06/15/2006
• Est. Priority Date: 12/13/2004
• Status: Active Grant

• Current Assignee: Dan John Glen Nephin, Glenn Patrick Hauck, Jackson Kit Wang
• Original Assignee: Dan John Glen Nephin, Glenn Patrick Hauck, Jackson Kit Wang
• Inventors: Wang, Jackson Kit, Nephin, Dan John Glen, Hauck, Glenn Patrick
• Granted Patent: US 7,298,328 B2
• Time in Patent Office: Days
• US Class Current: 342/451
• CPC Class Codes: G01S 5/0252 Radio frequency fingerprinting

Abstract

Methods, radios, components thereof, and other devices for localizing a geographic position of a radio receiver are provided. A current radio signature is obtained. The current radio signature comprises a plurality of measured signal qualities that collectively represent a frequency spectrum. Each measured signal quality in the plurality of measured signal qualities corresponds to a portion of the frequency spectrum. The current radio signature is compared with a plurality of reference radio signatures. Each reference radio signature in the plurality of reference radio signatures is associated with a global position. When the comparing identifies a unique match between the current radio signature and a reference radio signature in the plurality of reference radio signatures, the radio receiver is deemed to be localized to the global position associated with the reference radio signature.

Claims

1. A method of localizing a geographic position of a radio receiver, the method comprising:

obtaining a current radio signature, wherein said current radio signature comprises a plurality of measured signal qualities that collectively represent a frequency spectrum, each measured signal quality in said plurality of measured signal qualities corresponding to a portion of said frequency spectrum; and

comparing said current radio signature to a plurality of reference radio signatures, each reference radio signature in said plurality of reference radio signatures associated with a global position;

wherein

when said comparing identifies a unique match between said current radio signature and a reference radio signature in said plurality of reference radio signatures, said radio receiver is deemed to be localized to the global position associated with said reference radio signature.

2. The method of claim 1, wherein the frequency spectrum is all or a portion of the FM frequency spectrum.

3. The method of claim 1, wherein the frequency spectrum is all or a portion of the FM spectrum and all or a portion of the AM frequency spectrum.

4. The method of claim 1, wherein the frequency spectrum is all or a portion of the spectrum between 300 KHz and 3 MHz.

5. The method of claim 1, wherein the frequency spectrum is all or a portion of the spectrum between 3 MHz and 30 MHz.

6. The method of claim 1, wherein the frequency spectrum is all or a portion of the spectrum between 30 MHz and 300 MHz

7. The method of claim 1, wherein the frequency spectrum is all or a portion of the spectrum between 300 MHz and 3000 MHz.

8. The method of claim 1, wherein a measured signal quality in said plurality of measured signal qualities is a decibel rating of a frequency in said frequency spectrum.

9. The method of claim 1, wherein a measured signal quality in said plurality of measured signal qualities is a voltage representing a frequency in said frequency spectrum.

10. The method of claim 1, wherein the portion of said frequency spectrum corresponding to a first measured signal quality in said plurality of measured signal qualities is a first frequency window.

11. The method of claim 10, wherein said first frequency window comprises a frequency spectrum that has a spectral width that is between 1 KHz and 200 KHz.

12. The method of claim 10, wherein said first frequency window comprises a frequency spectrum that has a spectral width that is between 200 KHz and 400 KHz.

13. The method of claim 10, wherein the portion of said frequency spectrum corresponding to a second measured signal quality in said plurality of measured signal qualities is a second frequency window, and wherein a spectral width of said first frequency window and said second frequency window is the same.

14. The method of claim 10, wherein the portion of said frequency spectrum corresponding to a second measured signal quality in said plurality of measured signal qualities is a second frequency window, and wherein a spectral width of said first frequency window and said second frequency window is different.

15. The method of claim 10, wherein the first measured signal represents a strongest observable signal in the portion of said frequency spectrum corresponding to said first measured signal quality.

16. The method of claim 10, a second measured signal quality also corresponds to said first frequency window.

17. The method of claim 16, wherein the first measured signal quality and the second signal quality are each independently selected from the group consisting of an RDS quality, an FM multipath reading, FM level, AM level, or a phase lock.

18. The method of claim 1, wherein said plurality of reference radio signatures comprises between five reference radio signatures and one million reference radio signatures.

19. The method of claim 1, wherein said plurality of reference radio signatures comprises between one hundred reference radio signatures and fifty thousand reference radio signatures.

20. The method of claim 1, wherein said plurality of reference radio signatures comprises between five hundred reference radio signatures and twenty-five thousand reference radio signatures.

21. The method of claim 1, wherein each reference radio signature in said plurality of reference signatures corresponds to a unique global position in the United States, Canada, or Mexico.

22. The method of claim 1, wherein a reference radio signature in said plurality of reference radio signatures comprises a plurality of reference signal qualities, each reference signal quality in said plurality of reference signal qualities corresponding to said portion of the frequency spectrum.

23. The method of claim 22, wherein the portion of said frequency spectrum corresponding to a first reference signal quality in said plurality of reference signal qualities is a first frequency window.

24. The method of claim 23, wherein said first frequency window comprises a frequency spectrum that has a spectral width that is between 1 KHz and 200 KHz.

25. The method of claim 1, wherein said obtaining comprises scanning a predetermined range of frequencies to form a scan, and for each respective frequency in said predetermined range of frequencies in said scan, identifying a respective characteristic of said respective frequency.

26. The method of claim 25, wherein said characteristic of said frequency is a signal to noise ratio of said frequency or a signal strength of said frequency.

27. The method of claim 25, wherein said scanning is repeated a plurality of times to generate a plurality of scans and an average is taken of said respective characteristic of said respective frequency from said plurality of scans.

28. The method of claim 25, wherein the portion of said frequency spectrum corresponding to a measured signal quality in said plurality of measured signal qualities is a frequency window and wherein said measured signal quality for said frequency window is the characteristic of the frequency in said first frequency window having a value that is larger than the characteristic of any other frequency in the frequency window.

29. The method of claim 25, wherein the portion of said frequency spectrum corresponding to a measured signal quality in said plurality of measured signal qualities is a frequency window and wherein said measured signal quality for said frequency window is the characteristic of the frequency in said first frequency window having a value that is smaller than the characteristic of any other frequency in the frequency window.

30. The method of claim 25, wherein said identifying a respective characteristic of said respective frequency comprises measuring said respective characteristic of said respective frequency for less than 1 second.

31. The method of claim 25, wherein said identifying a respective characteristic of said respective frequency comprises measuring said respective characteristic more than 500 times per second and averaging the result of each said measurement.

32. The method of claim 1, wherein said comparing said current radio signature only compares nonsaturated signal qualities in said plurality of measured signal qualities.

33. The method of claim 1, the method further comprising normalizing said current radio signature prior to said comparing.

34. The method of claim 33, wherein said normalizing comprises removing a basal voltage present in said current radio signature.

35. The method of claim 1, wherein, when said comparing does not identify a unique match between said current radio signature and a reference radio signature, the method further comprises identifying a reference radio signature in said one or more references radios signatures as a function of a global position assigned to a past radio signature such that said radio receiver is deemed to be localized to the global position associated with said reference radio signature.

36. The method of claim 1, wherein said comparing comprises:

eliminating those reference radio signatures in said plurality of reference radio signatures that do not have an Nth largest signal quality at the same frequency as the Nth largest signal quality is said reference radio signature; and

repeating said eliminating using a different value for N, until a single reference radio signature in said plurality of reference radio signatures has not been eliminated.

37. The method of claim 1, wherein said plurality of reference radio signatures comprise a hash table and said comparing comprises a hash table lookup.

38. The method of claim 1, wherein said global position comprises a geometric polygon encompassing 5 square miles of area or less.

39. The method of claim 1, wherein said global position comprises a geometric polygon encompassing 5 square miles of area or less.

40. The method of claim 1, wherein said global position comprises a geometric polygon encompassing 1 square miles of area or less.

41. The method of claim 1, wherein said global position comprises a geometric polygon encompassing 5 contiguous acres of area or less.

42. The method of claim 1, the method further comprising providing information as a function of an identity of said reference radio signature that uniquely matches said current radio signature.

43. The method of claim 42, wherein said providing comprises

using said identity of said reference radio signature to lookup a message in a radio display table;

and

displaying said message.

44. The method of claim 43 wherein said message is related to traffic at a point within the global position of said reference radio signature that uniquely matches said current radio signature.

45. The method of claim 42, wherein the radio receiver is a radio data system or high density radio receiver, the method further comprising:

receiving an update of said radio display table.

46. The method of claim 42 wherein said message includes text, an alarm, a sound, an audible message, an audible instruction, or a song.

59. The method of claim 1, the method further comprising populating said plurality of reference radio signatures.

60. The method of claim 59, wherein a reference radio signature in said plurality of radio signatures is populated using a propagation model.

61. The method of claim 59, wherein a reference radio signature in said plurality of radio signatures is populated using an empirical model.

47. A device comprising:

instructions for accessing a radio signature lookup table, said radio signature lookup table comprising a plurality of reference radio signatures that collectively represent a frequency spectrum, each reference radio signature in said plurality of reference radio signatures associated with a global position;

a radio signature measurement model for localizing a geographic position of a device, the radio signature measurement model comprising instructions for obtaining a current radio signature, wherein said current radio signature comprises a plurality of measured signal qualities, each measured signal quality in said plurality of measured signal qualities corresponding to a portion of said frequency spectrum; and

a radio signature comparison module comprising instructions for comparing said current radio signature to said plurality of reference radio signatures.

48. The device of claim 47, the device further comprising:

instructions for accessing a radio display table, wherein said radio display table comprises information for each global position in a plurality of global positions; and

a radio display module for obtaining information from said radio display table as a function of an identity of a reference radio signature uniquely identified by said instructions for comparing.

49. The device of claim 48, the device further comprising a table update module, wherein said table update module comprises instructions for updating information in said radio display table.

50. The device of claim 47, the device further comprising a table update module, wherein said table update module comprises instructions for updating a reference radio signature in said radio signature lookup table.

51. The device of claim 47, wherein said instructions for accessing said radio signature lookup table and said radio signature measurement model are embedded in one or more application specific integrated circuits (ASICs), one or more field-programmable gate arrays (FPGAs), or any combination thereof.

52. The device of claim 47, wherein said device comprises an ASIC or FPGA.

53. The device of claim 47, wherein said device is a component of an RDS or an HD radio.

62. The device of claim 47, the device further comprising instructions for populating said radio signature lookup table.

63. The device of claim 62, wherein a reference radio signature in said radio signature lookup table is populated by said instructions for populating using a propagation model.

64. The device of claim 62, wherein a reference radio signature in said radio signature lookup table is populated by said instructions for populating using an empirical model.

54. A radio comprising:

means for accessing a radio signature lookup table, said radio signature lookup table comprising a plurality of reference radio signatures, each reference radio signature in said plurality of reference radio signatures associated with a global position;

means for localizing a geographic position of the radio, the radio signature measurement model comprising instructions for obtaining a current radio signature, wherein said current radio signature comprises a plurality of measured signal qualities that collectively represent a frequency spectrum, each measured signal quality in said plurality of measured signal qualities corresponding to a portion of said frequency spectrum; and

means for comparing said current radio signature to said plurality of reference radio signatures.

55. The radio of claim 54, the radio further comprising:

means for accessing a radio display table, wherein said radio display table comprises information for each global position in a plurality of global positions; and

means for obtaining information from said radio display table as a function of an identity of a reference radio signature uniquely identified by said means for comparing.

56. The radio of claim 55, the radio further comprising means for updating information in said radio display table.

57. The radio of claim 54, the radio further comprising means for updating a reference radio signature in said radio signature lookup table.

58. The radio of claim 54, wherein said means for accessing said radio signature lookup table and said radio signature measurement model is embedded in one or more application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs).

65. The radio of claim 54, the radio further comprising means for populating said radio signature lookup table.

66. The radio of claim 65, wherein a reference radio signature in said radio signature lookup table is populated by said instructions for populating using a propagation model.

67. The radio of claim 65, wherein a reference radio signature in said radio signature lookup table is populated by said instructions for populating using an empirical model.