Network of equivalent ground transmitters

• US 5,646,630 A
• Filed: 05/20/1996
• Issued: 07/08/1997
• Est. Priority Date: 05/20/1996
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Sheynblat, Leonid, Longaker, Harold Lewis
• Primary Examiner(s): Blum, Theodore M.
• Application Number:
  US08/650,731
• Time in Patent Office: 414 Days
• Field of Search: 342/357, 342/457, 342/463, 342/464, 364/449
• US Class Current: 342/357.31
• CPC Class Codes: G01S 19/071 DGPS corrections
• CPC Class Codes: G01S 19/11 wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters

Abstract

A system for differential navigation of an autonomous vehicle in the location with the limited visibility of the sky is disclosed. The system employs a plurality of satellites, a plurality of ground transmitters, and a base station. Different configurations for the minimum number of the satellites and the minimum number of ground transmitters are disclosed.

Claims

1. A system for accurate determination of the terrestrial position, timing coordinate, and velocity of an autonomous vehicle in real-time by transmitting signals from well-known locations, said system comprising:

a K-number of SATPS_j satellites, K being an integer, j being an integer less or equal to K, for generating satellite signals L(SATPS_j) for providing ranging, timing, and velocity information at the user'"'"'s location;

an N-number of ground transmitters (GT_i), N being an integer, i being an integer less or equal to N, for generating L(GT_i) signals for providing ranging, timing, and velocity information at the user'"'"'s location;

a base station (BS) for receiving said L(SATPS_j) signals from each said SATPS_j satellite, for receiving said L(GT_i) signals from each said GT_i, for calculating the differential correction data signal L(BS), and for transmitting the differential correction data signal L(BS) to said user'"'"'s location;

a 2N-number of ground transmitter communication links CLGT_i between each said GT_i and said user, and between each said GT_i and said base station (BS); and

a communication link CLB between said base station and said user;

wherein said user receives the L(SATPS_j) signals from each said satellite SATPS_j ; and

wherein said user receives the L(GT_i) signals from each said GT_i ; and

wherein said user receives said differential correction data signal L(BS) from said base station; and

wherein the location coordinates of each said GT_i and said base station are precisely known; and

wherein each said satellite SATPS_j includes a satellite clock with a known clock bias CB_SATPSj and a known clock drift CD_SATPSJ ; and

wherein each said GT_i includes a GT_i clock with an unknown clock bias CB_GTI and an unknown clock drift CD_GTi ; and

wherein said base station includes a base station clock with an unknown clock bias CB_BS and an unknown clock drift CD_BS.

2. The system of claim 1, wherein said K-number of SATPS_j satellites comprises at least one satellite, and wherein said N- number of ground transmitters (GT_i) comprises at least three GT_i, and wherein said user utilizes the satellite signals L(SATPS_j) generated by each said SATPS_j, and wherein said user employs the L(GT_i) signals generated by each said GT_i, and wherein said user uses the differential correction data signal L(BS) generated by said base station (BS) in order to determine in real-time said user'"'"'s position fixes, said user'"'"'s timing coordinate, and said user'"'"'s velocity.

3. The system of claim 1, wherein said K-number of SATPS_j satellites comprises at least two satellites, and wherein said N-number of ground transmitters (GT_i) comprises at least two GT_i, and wherein said user utilizes the satellite signals L(SATPS_j) generated by each said SATPS_j, and wherein said user employs the L(GT_i) signals generated by each said GT_i, and wherein said user uses the differential correction data signal L(BS) generated by said base station (BS) in order to determine in real-time said user'"'"'s position fixes, said user'"'"'s timing coordinate, and said user'"'"'s velocity.

4. The system of claim 1, wherein said K-number of SATPS_j satellites comprises at least three satellites, and wherein said N-number of ground transmitters (GT_i) comprises at least one GT_i, and wherein said user utilizes the satellite signals L(SATPS_j) generated by each said SATPS_j, and wherein said user employs the L(GT_i) signals generated by each said GT_i, and wherein said user uses the differential correction data signal L(BS) generated by said base station (BS) in order to determine in real-time said user'"'"'s position fixes, said user'"'"'s timing coordinate, and said user'"'"'s velocity.

5. The system of claim 1, wherein said communication link CLB includes a radiowave frequency band.

6. The system of claim 1, wherein said communication link CLB includes an infrared frequency band.

7. The system of claim 1, wherein said communication link CLB includes a microwave frequency band.

8. The system of claim 1, wherein said communication link CLB includes the ISM (industrial scientific medical) unlicensed operation band, and wherein the ISM band range is selected from a class of frequency range consisting of 900 MHz, 2.4 GHz, and 5.8 GHz;

and wherein the user can own the both ends of the ISM communication system.

9. The system of claim 1, wherein said communication link CLB includes a real time circuit switched communication link.

10. The system of claim 1, wherein said communication link CLB includes a 1.8 GHz band, wherein said 1.8 GHz band supports the personal communications services (PCS).

11. The system of claim 1, wherein said communication link CLB includes a system of Low Earth Orbiting Satellites (LEOS), a system of Medium Earth Orbiting Satellites (MEOS), or a system of Geostationary Earth Orbiting Satellites (GEOS), wherein said LEOS, MEOS, or GEOS systems are used to store and to forward digital packet data.

12. The system of claim 1, wherein said communication link CLB is selected from a class of radiowave communication links consisting of a cellular telephone communication means, paging signal receiving means, wireless messaging services, wireless application services, a wireless WAN/LAN station, and an Earth-satellite-Earth communication module that uses at least one satellite to relay a radiowave signal.

13. The system of claim 1, wherein said communication link CLB includes an Advanced. Mobile Phone System (AMPS) including a modem, and wherein said modem is selected from a class consisting of a DSP (digital signal processor) modem, and a cellular digital packet data (CDPD) modem.

14. The system of claim 1, wherein said communication link CLB includes a digital cellular telephone communication means, and wherein said digital cellular telephone communication means includes a means of modulation of digital data over a radiolink selected from a class consisting of a time division multiple access (TDMA) system, a code division multiple access (CDMA) system, and a frequency division multiple access (FDMA).

15. The system of claim 1, wherein at least one said communication link CLGT includes a radiowave frequency band.

16. The system of claim 1, wherein at least one said communication link CLGT includes an infrared frequency band.

17. The system of claim 1, wherein at least one said communication link CLGT includes a microwave frequency band.

18. The system of claim 1, wherein at least one said communication link CLGT includes the ISM (industrial scientific medical) unlicensed operation band, and wherein the ISM band range is selected from a class of frequency range consisting of 900 MHz, 2.4 GHz, and 5.8 GHz;

and wherein the user can own the both ends of the ISM communication system.

19. The system of claim 1, wherein at least one said communication link CLGT includes a real time circuit switched communication link.

20. The system of claim 1, wherein at least one said communication link CLGT includes a 1.8 GHz band, wherein said 1.8 GHz band supports the personal communications services (PCS).

21. The system of claim 1, wherein at least one said communication link CLGT includes a system of Low Earth Orbiting Satellites (LEOS), a system of Medium Earth Orbiting Satellites (MEOS), or a system of Geostationary Earth Orbiting Satellites (GEOS), wherein said LEOS, MEOS, or GEOS systems are used to store and to forward digital packet data.

22. The system of claim 1, wherein at least one said communication link CLGT is selected from a class of radiowave communication links consisting of a cellular telephone communication means, paging signal receiving means, wireless messaging services, wireless application services, a wireless WAN/LAN station, and an Earth-satellite-Earth communication module that uses at least one satellite to relay a radiowave signal.

23. The system of claim 1, wherein at least one said communication link CLGT includes an Advanced Mobile Phone System (AMPS) including a modem, and wherein said modem is selected from a class consisting of a DSP (digital signal processor) modem, and a cellular digital packet data (CDPD) modem.

24. The system of claim 1, wherein at least one said communication link CLGT includes a digital cellular telephone communication means, and wherein said digital cellular telephone communication means includes a means of modulation of digital data over a radiolink selected from a class consisting of a time division multiple access (TDMA) system, a code division multiple access (CDMA) system, and a frequency division multiple access (FDMA).

25. The system of claim 1, wherein at least one said GT comprises a pseudolite, and wherein at least one said communication link CLGT comprises a pseudo-GPS communication link, and wherein at least one said GT transmits pseudo-GPS signals.

26. A system for accurate determination of the terrestrial position, timing coordinate, and velocity of an autonomous vehicle in real-time by transmitting signals from well-known locations, said system comprising:

an N-number of ground transmitters (GT_i), wherein each said GT_i generates its own L(GT_i) signal for providing ranging, timing, and velocity information at the user'"'"'s location;

a base station (BS) for receiving said L(GT_i) signals from each said GT_i, for calculating the differential correction data signal L(BS), and for transmitting said differential correction data signal L(BS) to said user'"'"'s location;

a 2N-number of ground transmitter communication links CLGT_i between each said GT_i and said user, and between each said GT_i and said base station (BS); and

a communication link CLB between said base station and said user;

wherein said user receives the modulated by code L(GT_i) signals from each said GT_i ; and

wherein said user receives said differential correction data signal L(BS) from said base station; and

wherein the location coordinates of each said GT_i and said base station are precisely known; and

wherein each said GT_i includes a GT_i clock with an unknown clock bias CB_GTi and an unknown clock drift CD_GTi ; and

wherein said base station includes a base station clock with an unknown clock bias CB_BS and an unknown clock drift CD_BS.

27. The system of claim 26, wherein said N-number of ground transmitters (GT_i) comprises at least four GT_i, and wherein said user utilizes the L(GT_i) signals generated by each said GT_i and the differential correction data signal L(BS) generated by said base station (BS) in order to determine in real-time said user'"'"'s position fixes, said user'"'"'s timing coordinate, and said user'"'"'s velocity.

28. The system of claim 26, wherein said N-number of ground transmitters (GT_i) comprises at least one GT_i, and wherein said user utilizes the L(GT_i) signals generated by each said GT_i and the differential correction data signal L(BS) generated by said base station (BS) in order to determine in real-time said user'"'"'s timing coordinate.

29. The system of claim 26, wherein at least one said GT comprises a pseudolite, and wherein at least one said communication link CLGT comprises a pseudo-GPS communication link, and wherein at least one said GT transmits pseudo-GPS signals.

30. The system of claim 26, wherein said communication link CLB includes a radiowave frequency band.

31. The system of claim 26, wherein said communication link CLB includes an infrared frequency band.

32. The system of claim 26, wherein said communication link CLB includes a microwave frequency band.

33. The system of claim 26, wherein said communication link CLB includes the ISM (industrial scientific medical) unlicensed operation band, and wherein the ISM band range is selected from a class of frequency range consisting of 900 MHz, 2.4 GHz, and 5.8 GHz;

and wherein the user can own the both ends of the ISM communication system.

34. The system of claim 26, wherein said communication link CLB includes a real time circuit switched communication link.

35. The system of claim 26, wherein said communication link CLB includes a 1.8 GHz band, wherein said 1.8 GHz band supports the personal communications services (PCS).

36. The system of claim 26, wherein said communication link CLB includes a system of Low Earth Orbiting Satellites (LEOS), a system of Medium Earth Orbiting Satellites (MEOS), or a system of Geostationary Earth Orbiting Satellites (GEOS), wherein said LEOS, MEOS, or GEOS systems are used to store and to forward digital packet data.

37. The system of claim 26, wherein said communication link CLB is selected from a class of radiowave communication links consisting of a cellular telephone communication means, paging signal receiving means, wireless messaging services, wireless application services, a wireless WAN/LAN station, and an Earth-satellite-Earth communication module that uses at least one satellite to relay a radiowave signal.

38. The system of claim 26, wherein said communication link CLB includes an Advanced Mobile Phone System (AMPS) including a modem, and wherein said modem is selected from a class consisting of a DSP (digital signal processor) modem, and a cellular digital packet data (CDPD) modem.

39. The system of claim 26, wherein said communication link CLB includes a digital cellular telephone communication means, and wherein said digital cellular telephone communication means includes a means of modulation of digital data over a radiolink selected from a class consisting of a time division multiple access (TDMA) system, a code division multiple access (CDMA) system, and a frequency division multiple access (FDMA).

40. The system of claim 26, wherein at least one said communication link CLGT includes a radiowave frequency band.

41. The system of claim 26, wherein at least one said communication link CLGT includes art infrared frequency band.

42. The system of claim 26, wherein at least one said communication link CLGT includes a microwave frequency band.

43. The system of claim 26, wherein at least one said communication link CLGT includes the ISM (industrial scientific medical) unlicensed operation band, and wherein the ISM band range is selected from a class of frequency range consisting of 900 MHz, 2.4 GHz, and 5.8 GHz;

and wherein the user can own the both ends of the ISM communication system.

44. The system of claim 26, wherein at least one said communication link CLGT includes a real time circuit switched communication link.

45. The system of claim 26, wherein at least one said communication link CLGT includes a 1.8 GHz band, wherein said 1.8 GHz band supports the personal communications services (PCS).

46. The system of claim 26, wherein at least one said communication link CLGT includes a system of Low Earth Orbiting Satellites (LEOS), a system of Medium Earth Orbiting Satellites (MEOS), or a system of Geostationary Earth Orbiting Satellites (GEOS), wherein said LEOS, MEOS, or GEOS systems are used to store and to forward digital packet data.

47. The system of claim 26, wherein at least one said communication link CLGT is selected from a class of radiowave communication links consisting of a cellular telephone communication means, paging signal receiving means, wireless messaging services, wireless application services, a wireless WAN/LAN station, and an Earth-satellite-Earth communication module that uses at least one satellite to relay a radiowave signal.

48. The system of claim 26, wherein at least one said communication link CLGT includes an Advanced Mobile Phone System (AMPS) including a modem, and wherein said modem is selected from a class consisting of a DSP (digital signal processor) modem, and a cellular digital packet data (CDPD) modem.

49. The system of claim 26, wherein at least one said communication link CLGT includes a digital cellular telephone communication means, and wherein said digital cellular telephone communication means includes a means of modulation of digital data over a radiolink selected from a class consisting of a time division multiple access (TDMA) system, a code division multiple access (CDMA) system, and a frequency division multiple access (FDMA).

50. A method for accurate determination of the terrestrial position, timing coordinate, and velocity of an autonomous vehicle in real-time by transmitting signals from well-known locations, said method comprising the steps of:

providing a K-number of SATPS_j satellites;

generating satellite signals L(SATPS_j) by each said SATPS_j satellite for providing ranging, timing, and velocity information at the user'"'"'s location;

providing an N-number of ground transmitters;

generating ground transmitter L(GT_i) signals by each said GT_i for providing ranging, timing, and velocity information at the user'"'"'s location;

providing a base station (BS);

receiving the L(SATPS_j) signals from each said SATPS_j satellite by said base station (BS);

receiving the L(GT_i) signals from each said GT_i by said base station (BS);

calculating the differential correction data signal L(BS) by said base station (BS);

transmitting the differential correction data signal L(BS) to said user'"'"'s location by said base station (BS);

receiving the satellite L(SATPS_j) signals from each said satellite SATPS_j by said user;

receiving the L(GT_i) signals from each said GT_i by said user;

receiving the differential correction data signal L(BS) from said base station by said user; and

accurately determining the terrestrial position, timing coordinate, and velocity of the autonomous vehicle by said user.

51. The method of claim 50, further including a step of providing a synchronization signal to each said GT_i.

52. The method of claim 50, further including a step of initialization of each said GT_i, wherein said step of initialization includes a step of providing the location coordinates for each said GT_i.

53. A method for accurate determination of the terrestrial position, timing coordinate, and velocity of an autonomous vehicle in real-time by transmitting signals from well-known locations, said method comprising the steps of:

providing an N-number of ground transmitters;

generating ground transmitter L(GT_i) signals by each said GT_i for providing ranging, timing, and velocity information at the user'"'"'s location;

providing a base station (BS);

receiving the L(GT_i) signals from each said GT_i by said base station (BS);

calculating the differential correction data signal L(BS) by said base station (BS);

transmitting the differential correction data signal L(BS) to said user'"'"'s location by said base station (BS);

receiving the L(GT_i) signals from each said GT_i by said user;

receiving the differential correction data signal L(BS) from said base station by said user; and

accurately determining the terrestrial position, timing coordinate, and velocity of the autonomous vehicle by said user.

54. The method of claim 53, further including a step of providing a synchronization signal to each said GT_i.

55. The method of claim 53, further including a step of initialization of each said GT_i, wherein said step of initialization includes a step of providing the location coordinates for each said GT_i.