GPS receiver utilizing a communication link

• US 20010028321A1
• Filed: 01/18/2001
• Published: 10/11/2001
• Est. Priority Date: 10/09/1995
• Status: Active Grant

• Current Assignee: Norman Krasner
• Original Assignee: Norman Krasner
• Inventors: Krasner, Norman F.
• Granted Patent: US 6,421,002 B2
• Time in Patent Office: Days
• US Class Current: 342/357.1
• CPC Class Codes: G01S 19/06 employing an initial estimate of the location of the receiver as aiding data or in generating aiding data
• CPC Class Codes: G01S 19/071 DGPS corrections
• CPC Class Codes: G01S 19/09 providing processing capability normally carried out by the receiver
• CPC Class Codes: G01S 19/11 wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 19/254 relating to Doppler shift of satellite signals
• CPC Class Codes: G01S 19/256 relating to timing, e.g. time of week, code phase, timing offset
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 2205/008 using a mobile telephone network
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G01S 5/0045 Transmission from base station to mobile station G01S5/009 takes precedence
• CPC Class Codes: G01S 5/0054 of actual mobile position, i.e. position calculation on base station
• CPC Class Codes: G01S 5/009 Transmission of differential positioning data to mobile
• CPC Class Codes: G06F 2221/2111 Location-sensitive, e.g. geographical location, GPS
• CPC Class Codes: H01Q 1/273 Adaptation for carrying or wearing by persons or animals
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H03D 7/163 the local oscillations of at least two of the frequency changers being derived from a single oscillator
• CPC Class Codes: H03J 1/0008 using a central processing unit, e.g. a microprocessor digital tuning in general H03J5/0245
• CPC Class Codes: H03J 2200/11 : Cellular receiver, e.g. GSM, combined with a GPS receiver
• CPC Class Codes: H03J 7/04 : where the frequency control is accomplished by varying the electrical characteristics of a non-mechanically adjustable element or where the nature of the frequency controlling element is not significant
• CPC Class Codes: H03J 7/047 : Automatic frequency control using an auxiliary signal, e.g. low frequency scanning of the locking range or superimposing a special signal on the input signal
• CPC Class Codes: H03J 7/06 : using counters or frequency dividers
• CPC Class Codes: H04B 1/00 : Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
• CPC Class Codes: H04B 1/0007 : wherein the AD/DA conversion occurs at radiofrequency or intermediate frequency stage
• CPC Class Codes: H04B 1/28 : the receiver comprising at least one semiconductor device having three or more electrodes
• CPC Class Codes: H04B 1/3805 : with built-in auxiliary receivers

Abstract

Methods and apparatuses for deriving an approximate Doppler for a satellite positioning system (SPS) receiver from an approximate location which is obtained from a cellular communication system information source. In one embodiment, an approximate location of the SPS receiver is derived from the information source and this approximation location is used to determine approximate Dopplers to a plurality of SPS satellites at a given time. The approximate Dopplers are then used to reduce processing time in either determining pseudoranges to the SPS satellites or acquiring signals from the SPS satellites. In another aspect of the invention, a reference signal is used to provide a local oscillator signal which is used to acquire SPS signals in an SPS receiver. This reference signal is extracted from a data signal modulated on a carrier frequency. The data signal on the carrier frequency is transmitted from, in one example, a wireless cell site which is communicating with the SPS receiver which has a cellular based communication receiver.

Claims

1. A method for reducing processing time in a satellite positioning system (SPS) receiver having a cell based communication receiver, said method comprising:

determining an approximate location of said SPS receiver from a cell based information source, said approximate location being determined by at least one of a location of a cellular service area which includes a cell site or a location of said cell site;

determining an approximate Doppler for at least one SPS satellite relative to said SPS receiver, said approximate Doppler being based on said approximate location;

using said approximate Doppler in said SPS receiver to reduce processing time in one of either determining at least one pseudorange to said at least one SPS satellite or acquiring signals from said at least one SPS satellite.

2. A method as in

claim 1

further comprising:

transmitting said approximate Doppler from said cell site to said cell based communication receiver and wherein said cell site is capable of communicating with said cell based communication receiver.

3. A method as in

claim 2

wherein said approximate location is determined by either a selected position in a general geographical region defined by said cellular service area or said location of said cell site which is located in a portion of said general geographical region.

4. A method as in

claim 2

further comprising:

transmitting said at least one pseudorange from said SPS receiver to a remote processing station.

5. A method as in

claim 4

wherein said transmitting step is through said cell site.

6. A method as in

claim 5

wherein said remote processing station is located at said cell site.

7. A method as in

claim 5

wherein said remote processing station is coupled to a cellular switching center.

8. A method as in

claim 7

wherein said approximate Doppler is determined by said remote processing station.

9. A method as in

claim 8

wherein said remote processing station receives said approximate location from said cell site and provides said approximate Doppler to said SPS receiver through said cell site.

10. A method as in

claim 8

wherein said remote processing station receives a cell site identifier from said cell site and determines said approximate location from said cell site identifier and provides said approximate Doppler to said SPS receiver through said cell site.

11. A method as in

claim 10

wherein said remote processing station comprises a storage device having a table which relates said cell site identifier to said approximate location and wherein said remote processing station has access to information specifying a plurality of approximate Dopplers at a given time for said approximate location.

12. A method as in

claim 1

further comprising:

transmitting said at least one pseudorange from said SPS receiver to a remote processing station through said cell site, and wherein said cell based communication receiver is integrated in one enclosure with said SPS receiver.

13. A method as in

claim 12

wherein said remote processing station is coupled to a cellular switching center which is coupled to a plurality of cell sites, including said cell site.

41. A method as in

claim 1

wherein said cell based communication receiver determines said approximate location from a cellular transmission from said cell site and wherein said cell based communication receiver transmits said approximate location to a remote processing station which determines said approximate Doppler and causes said approximate Doppler to be transmitted from said cell site to said cell based communication receiver.

55. A method as in

claim 1

further comprising:

transmitting said approximate Doppler from said cell site to said cell based communication receiver, wherein said approximate Doppler is determined by a remote processing station which is coupled to said cell site and which receives an identifier of at least one of said cellular service area or said cell site from said cell based communication receiver.

56. A method as in

claim 55

wherein said remote processing station determines said approximate Doppler from said identifier which is transmitted by said cell based communication receiver to said remote processing station.

57. A method as in

claim 56

wherein said identifier is provided by said cell site to said cell based communication receiver, and said cell based communication receiver transmits said identifier through said cell site to said remote processing station.

58. A method as in

claim 56

wherein said cell based communication receiver derives said identifier from a signal transmitted by said cell site to said cell based communication receiver.

59. A method as in

claim 58

wherein said signal is a pseudorandom (PN) code which corresponds to said cell site.

60. A method as in

claim 59

wherein said signal is transmitted in a CDMA system.

61. A method as in

claim 1

wherein said approximate Doppler is determined at a remote processing station which causes said approximate Doppler to be transmitted from said cell site to said cell based communication receiver, and wherein said cell based communication receiver causes said at least one pseudorange to be transmitted to said remote processing station which determines a position information for said SPS receiver using said at least one pseudorange, and wherein said SPS receiver uses said approximate Doppler without extracting satellite position data from SPS signals from SPS satellites.

62. A method as in

claim 1

further comprising:

determining a reference signal from a communication signal transmitted from said cell site to said cell based communication receiver;

using said reference signal to provide a local oscillator signal which is used to acquire SPS signals in said SPS receiver.

63. A method as in

claim 62

wherein said reference signal is determined from a data signal modulated on a carrier frequency of said communication signal.

64. A method as in

claim 62

wherein said reference signal is determined from a carrier frequency of said communication signal.

14. A method of using a data processing station which is capable of being coupled to at least one wireless cell site, said method comprising:

receiving a site information which determines an approximate location, said approximate location being determined by at least one of a location of a cellular service area which includes said wireless cell site or a location of said wireless cell site;

determining an approximate Doppler for at least one SPS satellite, said approximate Doppler being based on said approximate location;

transmitting said approximate Doppler to said wireless cell site.

15. A method as in

claim 14

further comprising:

receiving at least one pseudorange from said wireless cell site, said pseudorange being provided by a satellite positioning system (SPS) receiver having a cell based communication receiver which is capable of communicating with said wireless cell site.

16. A method as in

claim 15

further comprising:

transmitting a request for a position information from said SPS receiver, said request being transmitted to said wireless cell site.

17. A method as in

claim 16

wherein said step of transmitting a request occurs after said step of transmitting said approximate Doppler.

18. A method as in

claim 15

wherein said data processing station is capable of being coupled to a plurality of wireless cell sites.

19. A method as in

claim 15

wherein said site information identifies said wireless cell site and wherein said data processing station determines said approximate location from said site information.

20. A method as in

claim 15

wherein said site information provides said approximate location.

21. A method as in

claim 15

wherein said data processing station accesses a storage device which contains information specifying a plurality of approximate Dopplers at a given time.

22. A method as in

claim 15

wherein said approximate location and said at least one pseudorange are used to calculate a position information for said SPS receiver.

44. A method as in

claim 15

further comprising:

transmitting a signal having a carrier frequency and a data signal modulated on said carrier frequency, said SPS receiver using one of said carrier frequency and said data signal to provide a local oscillator signal which is used to acquire SPS signals.

23. A data processing station comprising:

a processor;

a storage device coupled to said processor;

a transceiver coupled to said processor, said transceiver for coupling said data processing station to a wireless cell site, said storage device containing information specifying at least one approximate Doppler at a given time for an approximate location determined by at least one of a location of a cellular service area which includes said wireless cell site or a location of said wireless cell site, said transceiver receiving a site information which determines said approximate location, said processor determining an approximate Doppler for at least one SPS satellite, said approximate Doppler being based on said approximate location, and said transceiver sending said approximate Doppler to said wireless cell site.

24. A data processing station as in

claim 23

further comprising:

a source of SPS signals coupled to said processor, and wherein said transceiver receives at least one pseudorange from said wireless cell site and wherein said processor uses said SPS signals and said at least one pseudorange to determine a position information for a satellite position system (SPS) receiver which is capable of communicating with said wireless cell site.

25. A data processing system as in

claim 24

wherein said data processing system is capable of being coupled to another data processing system which issues a request to provide said position information to said another data processing system.

26. A data processing system as in

claim 25

wherein said data processing system and said another data processing system are coupled through the Internet.

27. A data processing system as in

claim 24

wherein said source of SPS signals comprises one or more SPS receivers.

28. A computer readable medium containing executable computer program instructions which, when executed by a data processing system, cause said data processing system to perform steps comprising:

receiving a site information which determines an approximate location, said approximate location being determined by at least one of a location of a cellular service area which includes a wireless cell site which is capable of being coupled to said data processing system or a location of said wireless cell site;

determining an approximate Doppler for at least one SPS satellite, said approximate Doppler being based on said approximate location;

transmitting said approximate Doppler to said wireless cell site.

29. A computer readable medium as in

claim 28

wherein said steps further comprise:

receiving a source of SPS signals;

receiving at least one pseudorange from said wireless cell site;

processing said at least one pseudorange and said SPS signals to determine a position information for an SPS receiver which provided said at least one pseudorange.

30. A computer readable medium as in

claim 29

wherein said approximate location and said SPS signals and said at least one pseudorange are processed to determine said position information.

31. A method for providing a local oscillator signal in a mobile satellite positioning system (SPS) receiver, said method comprising:

receiving a signal having a carrier frequency and a data signal modulated on said carrier frequency;

extracting a reference signal from said data signal modulated on said carrier frequency;

using said reference signal to provide a local oscillator signal to acquire SPS signals.

32. A method as in

claim 31

wherein said data signal modulated on said carrier frequency comprises a pseudorandom sequence.

33. A method as in

claim 31

wherein said signal operates in either a code division multiple access system or a time division multiple access system.

34. A method as in

claim 31

wherein said extracting step comprises automatically locking to said data signal modulated on said carrier frequency.

35. A method as in

claim 31

wherein said using step comprises comparing said reference signal to an oscillator signal generated by a local oscillator in said SPS receiver.

36. A method as in

claim 31

wherein said using step comprises providing said reference signal to a frequency synthesizer and producing said local oscillator signal from said reference signal and said frequency synthesizer.

37. A method as in

claim 35

wherein said oscillator signal is calibrated by said reference signal to provide said local oscillator signal.

38. A method as in

claim 31

wherein said data signal modulated on said carrier frequency is a digital signal.

39. A method for determining a position of a satellite positioning system (SPS) receiver having a wireless cell based transmitter, said method comprising:

determining an approximate location of said SPS receiver from a cell based information source, said approximate location being determined by at least one of a location of a cellular service area which includes a wireless cell site which is capable of communicating with said cell based transmitter or a location of said wireless cell site;

receiving a source of SPS signals;

receiving a plurality of pseudorange data from said wireless cell based transmitter, said plurality of pseudorange data being determined by said SPS receiver;

computing a position information of said SPS receiver by using SPS signals, said plurality of pseudoranges and said approximate location.

40. A method as in

claim 39

further comprising:

transmitting a signal having a carrier frequency and a data signal modulated on said carrier frequency, said SPS receiver using one of said carrier frequency and said data signal to provide a local oscillator signal which is used to acquire SPS signals.

42. A method as in

claim 39

further comprising:

determining an approximate Doppler for at least one SPS satellite relative to said SPS receiver, said approximate Doppler being based on said approximate location;

transmitting said approximate Doppler to said SPS receiver through said wireless cell site.

43. A method as in

claim 42

further comprising:

transmitting a signal having a carrier frequency and a data signal modulated on said carrier frequency, said SPS receiver using one of said carrier frequency and said data signal to provide a local oscillator signal which is used to acquire SPS signals.

45. A method for providing Doppler information to a satellite positioning system (SPS) receiver, said method comprising:

determining a plurality of approximate Doppler data from an approximate location based upon at least one of a location of a wireless cell site or a location of a cellular service area which includes said wireless cell site, said plurality of approximate Doppler data for a corresponding plurality of satellites;

broadcasting said plurality of approximate Doppler data from a wireless cellular transmitter of said wireless cell site to a plurality of SPS receivers in a cell serviced by said wireless cell site.

46. A method as in

claim 45

further comprising:

receiving at least one pseudorange from said wireless cell site, said pseudorange being provided by an SPS receiver having a cell based wireless transmitter which communicates with said wireless cell site.

47. A method as in

claim 46

further comprising:

computing a position information of said SPS receiver by using SPS signals from a source of SPS signals and using said pseudorange and said approximate location.

48. A method as in

claim 46

further comprising:

transmitting a signal having a carrier frequency and a data signal modulated on said carrier frequency, said SPS receiver using one of said carrier frequency and said data signal to provide a local oscillator signal which is used to acquire SPS signals.

49. A method for providing a satellite information to a satellite positioning system (SPS) receiver, said method comprising:

determining an approximate location from a cell based information source, said approximate location being based on at least one of a location of a cellular service area which includes a wireless cell site and a location of said wireless cell site, and determining a plurality of satellite ephemeris data for a corresponding plurality of satellites, which are in view of said approximate location;

transmitting said plurality of satellite ephemeris data from a wireless cellular transmitter of said wireless cell site to an SPS receiver in a cell serviced by said wireless cell site.

50. A method as in

claim 49

wherein said transmitting step comprises broadcasting said plurality of satellite ephemeris data to a plurality of SPS receivers in said cell.

51. A method as in

claim 49

further comprising:

receiving a plurality of pseudorange data from said SPS receiver, said plurality of pseudorange data being determined by said SPS receiver.

52. A method as in

claim 51

further comprising:

computing a position information of said SPS receiver by using SPS signals from a source of SPS signals and said plurality of pseudoranges.

53. A method as in

claim 52

wherein said position information is computed by also using said approximate location.

54. A method as in

claim 52

further comprising:

transmitting a signal having a carrier frequency and a data signal modulated on said carrier frequency, said SPS receiver using one of said carrier frequency and said data signal to provide a local oscillator signal which is used to acquire SPS signals.

65. A combined mobile satellite positioning system (SPS) receiver and a communication receiver, said SPS receiver and communication receiver comprising:

a first antenna which receives a communication signal having a data signal modulated on a carrier frequency;

a data signal acquisition and tracking circuit coupled to said first antenna, said acquisition and tracking circuit producing a reference signal from the data signal;

a frequency synthesizer coupled to said acquisition and tracking circuit to receive said reference signal, said frequency synthesizer providing a local oscillator signal to acquire SPS signals in said SPS receiver.

66. A combined SPS receiver and communication receiver as in

claim 65

further comprising:

a voltage controlled oscillator (VCO) in said acquisition and tracking circuit, said VCO providing said reference signal; and

wherein said data signal comprises a pseudorandom sequence.

67. A combined SPS receiver and communication receiver as in

claim 65

wherein said reference signal is generated by locking to said data signal.

68. A method for determining a position information of a mobile satellite positioning system (SPS) receiver having a cell based communication receiver, said method comprising:

receiving a plurality of differential SPS correction data for a plurality of different locations;

selecting a first differential SPS correction data for a first location from said plurality of differential SPS correction data, said first differential SPS correction data being selected based upon an approximate location which is determined from a cell based information source by at least one of a location of a cellular service area which includes a cell site or a location of said cell site;

receiving a plurality of pseudorange data from said SPS receiver, said plurality of pseudorange data and said first differential SPS correction data being used to determine said position.

69. A method as in

claim 68

further comprising:

receiving satellite ephemeris data which is used to determine said position.

70. A method as in

claim 69

wherein said position is determined at a data processing station which is capable of communicating with said cell based communication receiver through a cell based communication system which includes said cell site.

71. A method as in

claim 70

wherein said SPS receiver provides a site information to said data processing station which uses said site information to determine said approximate location.

72. A method as in

claim 71

further comprising:

determining an approximate Doppler for at least one SPS satellite relative to said SPS receiver, said approximate Doppler being based on said approximate location;

transmitting said approximate Doppler to said SPS receiver;

using said approximate Doppler in said SPS receiver.

73. A method as in

claim 70

further comprising:

determining an approximate Doppler for at least one SPS satellite relative to said SPS receiver, said approximate Doppler being based on said approximate location;

transmitting said approximate Doppler to said SPS receiver;

using said approximate Doppler in said SPS receiver.

74. A method for determining Doppler information in a satellite positioning system (SPS) receiver having a cell based communication receiver, said method comprising:

receiving, at said SPS receiver, satellite almanac information for a plurality of SPS satellites in view of said SPS receiver;

determining an approximate location of said SPS receiver, said approximate location being determined by at least one of a location of a cellular service area which includes a cell site or a location of said cell site;

using said satellite almanac information and said approximate location to determine an approximate Doppler for at least one of said SPS satellites.