Long baseline RTK using a secondary base receiver and a non-continuous data link

• US 6,317,603 B1
• Filed: 05/21/1999
• Issued: 11/13/2001
• Est. Priority Date: 05/21/1999
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Allison, Michael Timo
• Primary Examiner(s): Maung, Nay
• Assistant Examiner(s): WEST, LEWIS G
• Application Number:
  US09/316,400
• Time in Patent Office: 907 Days
• Field of Search: 455/456, 701/214, 701/215, 701/213, 701/2, 342/357.06, 342/357.08, 342/357.1
• US Class Current: 455/456.1
• CPC Class Codes: G01S 19/04 providing carrier phase data
• CPC Class Codes: G01S 19/43 using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry

Abstract

The system and method for long baseline RTK survey are disclosed. The system includes a primary base station (PBS), a secondary base station (SBS), a primary data link between the PBS and the SBS, and a secondary data link between the SBS and a rover. The PBS, the SBS, and the rover are equipped with satellite antennas for satellite navigational purposes. The long baseline vector between the PBS and the rover is established by combining the primary baseline vector between the SBS and the PBS and the secondary baseline vector between the SBS and the rover. The PBS is placed in a position with a known location. The final SBS position is accurately determined using the PBS position during two initialization steps.

Claims

1. A system for long baseline real time kinematic positioning (LBRTK) comprising:

a primary base station (PBS);

a secondary base station (SBS);

a primary data link between said SBS and said PBS; and

a secondary data link between said SBS and a rover;

wherein said PBS is configured to transmit data to said SBS using said primary data link,

and wherein said SBS is configured to compute a secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted data from said PBS;

and wherein said rover is configured to perform an RTK survey using said SBS_P transmitted to said rover using said secondary data link.

2. The system of claim 1, wherein said PBS further comprises:

a primary base multi-frequency satellite antenna configured to receive a first plurality of broadcast satellite signals;

a primary base satellite receiver configured to continuously obtain a first plurality of satellite observables using said first plurality of received satellite signals; and

a primary base data storage configured to log each said satellite observable obtained from said first plurality of received satellite signals at a first predetermined interval.

3. The system of claim 1, wherein said PBS further comprises:

a primary base multi-frequency satellite antenna configured to receive a first plurality of broadcast satellite signals; and

a primary base satellite receiver configured to continuously obtain a first plurality of satellite observables using said first plurality of received satellite signals.

4. The system of claim 2, wherein said SBS further comprises:

a secondary base multi-frequency satellite antenna configured to receive a second plurality of broadcast satellite signals;

a secondary base satellite receiver configured to continuously obtain a second plurality of satellite observables using said second plurality of received satellite signals; and

a secondary base data storage configured to log each said satellite observable obtained from said second plurality of received satellite signals at a second predetermined interval.

5. The system of claim 1, wherein said SBS further comprises:

a secondary base multi-frequency satellite antenna configured to receive a second plurality of broadcast satellite signals; and

a secondary base satellite receiver configured to continuously obtain a second plurality of satellite observables using said second plurality of received satellite signals.

6. The system of claim 1, wherein said primary data link further comprises:

a primary two-way data link.

7. The system of claim 6, wherein said primary two-way data link further comprises:

a cellular telephone link.

8. The system of claim 6, wherein said primary two-way data link further comprises:

a radio link.

9. The system of claim 6, wherein said primary two-way data link further comprises:

an electronic mail link.

10. The system of claim 6, wherein said primary two-way data link further comprises:

a satellite link.

11. The system of claim 1, wherein said primary data link further comprises:

a primary one-way data link, wherein said PBS is configured to transmit a compressed data set to said SBS using said primary one-way data link according to a predetermined schedule.

12. The system of claim 1, wherein said secondary data link further comprises:

a secondary one-way data link.

13. The system of claim 12, wherein said secondary one-way data link further comprises:

a radio link.

14. The system of claim 12, wherein said secondary one-way data link further comprises:

an optical link.

15. The system of claim 4;

wherein said primary base data storage further comprises;

a circular storage system configured to log a plurality of carrier phases, and time tags for said first plurality of satellite observables;

wherein said secondary base data storage further comprises;

a data storage system configured to log a plurality of carrier phases, and time tags for said second plurality of satellite observables;

and wherein said PBS data logged in said circular storage system and said SBS data logged in said data storage system are used for computation a primary baseline vector between said PBS and said SBS.

16. A system for long baseline real time kinematic positioning (LBRTK) for a plurality of rovers comprising:

a primary base station (PBS);

a plurality of secondary base stations (SBS);

a plurality of primary data links between said SBS and each said PBS; and

a plurality of secondary data links, wherein each said SBS and each said rover are linked by at least one said secondary data link;

wherein said PBS is configured to transmit a compressed data set to each said SBS using one said primary data link;

and wherein each said SBS is configured to compute one said secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted compressed data set from said PBS;

and wherein each said rover is configured to perform an RTK survey using at least one said SBS_P transmitted to said rover using at least one said secondary data link.

17. A system for long baseline real time kinematic positioning (LBRTK) comprising:

a secondary base station (SBS);

a primary data link between said SBS and a primary base station (PBS); and

a secondary data link between said SBS and a rover;

wherein said PBS is configured to transmit a compressed data set to said SBS using said primary data link,

and wherein said SBS is configured to compute a secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted compressed data set from said PBS;

and wherein said rover is configured to perform an RTK survey using said SBS_P transmitted to said rover using said secondary data link.

18. A system for long baseline real time kinematic positioning (LBRTK) for a plurality of rovers comprising:

a plurality of secondary base stations (SBS);

a plurality of primary data links between each said SBS and a primary base station (PBS); and

a plurality of secondary data links between a plurality of rovers and said plurality of SBS, wherein each said SBS and each said rover are linked by using at least one said secondary data link;

wherein said PBS is configured to transmit a compressed data set to each said SBS using one said primary data link;

and wherein each said SBS is configured to compute one said secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted compressed data set from said PBS;

and wherein each said rover is configured to perform an RTK survey using at least one said SBS_P transmitted to said rover using at least one said secondary data link.

19. A method for long baseline real time kinematic positioning (LBRTK) comprising the following steps:

(a) receiving a first plurality of broadcast satellite signals by utilizing a primary base station (PBS) comprising a primary base multi-frequency satellite antenna;

(b) continuously obtaining a first plurality of satellite observables using a primary base satellite receiver configured to utilize said first plurality of received satellite signals;

(c) logging each said satellite observable obtained from said first plurality of received satellite signals at a first predetermined interval using a primary base data storage;

(d) receiving a second plurality of broadcast satellite signals by using a secondary base station (SBS) comprising a secondary base multi-frequency Satellite antenna;

(e) continuously obtaining a second plurality of satellite observables using said second plurality of received satellite signals by utilizing a secondary base satellite receiver;

(f) logging each said satellite observable obtained from said second plurality of received satellite signals at a second predetermined interval by utilizing a secondary base data storage;

(g) transmitting said PBS logged data from said PBS to said SBS using a primary data link;

(h) computing a secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted PBS data;

wherein said SBS_P relative to said PBS_P comprises a primary baseline; and

(i) performing an RTK survey by a rover, wherein said rover is configured to receive said SBS_P transmitted to said rover using a secondary data link between said SBS and said rover.

20. The method of claim 19, wherein said step (g) of transmitting said PBS logged data from said PBS to said SBS using said primary data link further includes the steps of:

transmitting a request for said PBS data to said PBS using a two-way primary data link between said PBS and said SBS; and

transmitting said requested PBS data to said SBS from said PBS using said two-way primary data link.

21. The method of claim 19, wherein said step (g) of transmitting said PBS logged data from said PBS to said SBS using said primary data link further includes the steps of:

transmitting said PBS logged data to said SBS from said PBS using said one-way primary data link according to a predetermined schedule.

22. A method of RTK surveying of a plurality of survey marks employing a rover, a primary base station (PBS), and a secondary base station (SBS), wherein said SBS and said PBS comprise a long baseline, said method comprising the steps of:

(a) setting up said PBS in a location having an known position;

(b) setting up said SBS in a location having an unknown position, wherein said SBS location is set to provide a secondary communication link to said rover;

(c) starting said PBS to automatically log a first plurality of satellite observables at a first predetermined rate;

(d) storing said continuously logged PBS data in a primary database storage;

(e) starting said SBS to automatically log a second plurality of satellite observables at a second predetermined rate;

(f) storing said continuously logged SBS data in a secondary database storage;

(g) initiating by said SBS a primary two-way communication link between said PBS and said SBS;

(h) sending a request for a first PBS data transfer by said SBS to said PBS, wherein said requested first PBS data comprises PBS data logged during a time period between a time instance when said first sending request was sent and a time instance when said SBS was turned on;

(i) accessing said primary PBS database storage, compressing said requested first PBS data, and sending said first requested compressed PBS data set to said SBS using said primary two-way communication link;

(k) matching said first logged SBS data with said first transmitted compressed PBS data set;

(l) computing an initial secondary base position (SBS_P) relative to a primary base station position (PBS_P) by utilizing said first transmitted compressed PBS data set and said first logged matched SBS data;

(m) continuously transmitting from said SBS to said rover initial data using said secondary communication link, wherein said initial data includes said SBS_IP; and

(n) performing RTK surveying of each said survey mark by said rover.

23. The method of claim 22, wherein said step (n) of performing said RTK surveying of a plurality of survey marks by said rover further includes the steps of:

(n1) performing RTK surveying of a first survey mark by computing an initial rover position relative to said SBS_P using said initial data transmitted from said SBS;

wherein said rover position relative to said SBS_IP comprises a secondary baseline; and

by adjusting said initial rover position; and

(n2) repeating said step (n1) for each said survey mark.

24. The method of claim 22, wherein said step (n) of performing said RTK surveying by said rover a plurality of survey marks further includes the steps of:

(n1) computing an initial rover position relative to said SBS using said initial data transmitted from said SBS;

(n2) continuously logging said PBS data at said first predetermined rate and storing said continuously logged PBS data in said primary database storage;

(n3) sending a second request for a PBS data transfer by said SBS to said PBS, wherein said requested second PBS data comprises final PBS data logged during a final time period substantially sufficient to enable the computation of a final SBS_P (SBS_FP) with a required accuracy;

(n4) accessing said primary PBS database storage, compressing said second requested logged PBS data, and sending said second compressed PBS data set to said SBS using said primary two-way communication link;

(n5) computing said final secondary base position (SBS_FP) relative to a primary base station position (PBS_P) by using a post-processing technique;

(n6) checking a plurality of statistical indicators to ensure a correct solution for said SBS_FP;

(n7) continuously transmitting from said SBS to said rover final data including said SBS_FP using said secondary communication link;

(n8) computing a final rover position relative to said SBS using said final data transmitted from said SBS;

wherein said final rover position determines a first survey mark; and

(n9) repeating said steps (n1-n8) for each said survey mark.

25. The method of claim 24, wherein said step (n3) of sending a second request for a PBS data transfer further includes the step of:

checking the level of multipath distortion during said final time period of PBS data logging.

26. A method of RTK surveying of a plurality of survey marks employing a rover, a primary base station (PBS), and a secondary base station (SBS), wherein said SBS and said PBS comprise a long baseline, said method comprising the steps of:

(a) setting up said PBS in a location having an known position;

(b) setting up said SBS in a location having an unknown position, wherein said SBS location is set to provide a secondary communication link to said rover;

(c) starting said PBS to automatically log a first plurality of satellite observables at a first predetermined rate;

(d) storing said continuously logged PBS data in a primary database storage;

(e) starting said SBS to automatically log a second plurality of satellite observables at a second predetermined rate;

(f) storing said continuously logged SBS data in a secondary database storage;

(g) accessing said primary PBS database storage, compressing first PBS data, and sending said first compressed PBS data set to said SBS using a one-way primary communication link according to a predetermined schedule;

(h) matching said first logged SBS data with said first transmitted compressed PBS data set;

(i) computing an initial secondary base position (SBS_P) relative to a primary base station position (PBS_P) by utilizing said first transmitted compressed PBS data set and said first logged matched SBS data;

(k) continuously transmitting from said SBS to said rover initial data using said secondary communication link, wherein said initial data includes said SBS_IP; and

(l) performing RTK surveying by said rover.

27. The method of claim 26, wherein said step (l) of performing said RTK surveying of a plurality of survey marks by said rover further includes the step of:

(l1) performing RTK survey of a first survey mark by computing an initial rover position relative to said SBS_P using said initial data transmitted from said SBS;

wherein said rover position relative to said SBS_P comprises a secondary baseline; and

by adjusting said initial rover position; and

(l2) repeating said step (l1) for each said survey mark.

28. The method of claim 26, wherein said step (l) of performing said RTK surveying of a plurality of survey marks by said rover further includes the steps of:

(l1) computing an initial rover position relative to said SBS using said initial data transmitted from said SBS;

(l2) continuously logging said PBS data at said first predetermined rate and storing said continuously logged PBS data in said primary database storage;

(l3) accessing said primary PBS database storage, compressing second logged PBS data, and sending said second compressed PBS data to said SBS using said primary one-way communication link;

(l4) computing a final secondary base position (SBS_FP) relative to a primary base station position (PBS_P) by using a post-processing technique;

(l5) checking a plurality of statistical indicators to ensure a correct solution for said SBS_FP;

(l6) continuously transmitting from said SBS to said rover final data including said SBS_FP using said secondary communication link;

(l7) performing RTK survey of a first survey mark by computing a final rover position relative to said SBS using said final data transmitted from said SBS; and

(l8) repeating said steps (l1-l7) for each said survey mark.

29. A method for long baseline real time kinematic positioning (LBRTK) comprising the following steps:

(a) receiving a first plurality of broadcast satellite signals by utilizing a primary base station (PBS) comprising a primary base multi-frequency satellite antenna;

(b) continuously obtaining a first plurality of satellite observables using a primary base satellite receiver configured to utilize said first plurality of received satellite signals;

(c) logging each said satellite observable obtained from said first plurality of received satellite signals at a first predetermined interval using a primary base data storage;

(d) receiving a second plurality of broadcast satellite signals by using a secondary base station (SBS) comprising a secondary base multi-frequency Satellite antenna;

(e) continuously obtaining a second plurality of satellite observables using said second plurality of received satellite signals by utilizing a secondary base satellite receiver;

(f) logging each said satellite observable obtained from said second plurality of received satellite signals at a second predetermined interval by utilizing a secondary base data storage;

(g) transmitting said PBS logged data from said PBS to said SBS using a primary data link;

(h) computing a secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted PBS data;

wherein said SBS_P relative to said PBS_P comprises a primary baseline; and

(i) transmitting said SBS_P to a rover using a secondary data link between said SBS and said rover.

30. The method of claim 29, wherein said step (g) of transmitting said PBS logged data from said PBS to said SBS using said primary data link further includes the steps of:

transmitting a request for said PBS data to said PBS using a two-way primary data link between said PBS and said SBS; and

transmitting said requested PBS data to said SBS from said PBS using said two-way primary data link.

31. The method of claim 29, wherein said step (g) of transmitting said PBS logged data from said PBS to said SBS using said primary data link further includes the steps of:

transmitting said PBS logged data to said SBS from said PBS using said one-way primary data link according to a predetermined schedule.

32. A method of RTK surveying comprising the steps of:

(1) setting up a primary base station (PBS) in a location having an known position;

(2) setting up a secondary base station (SBS) in a location having an unknown position, wherein said SBS location is set to provide a secondary communication link to a rover;

(3) starting said PBS to automatically log a first plurality of satellite observables at a first predetermined rate;

(4) storing said continuously logged PBS data in a primary database storage;

(5) starting said SBS to automatically log a second plurality of satellite observables at a second predetermined rate;

(6) storing said continuously logged SBS data in a secondary database storage;

(7) initiating by said SBS a primary two-way communication link between said PBS and said SBS;

(8) sending a request for a first PBS data transfer by said SBS to said PBS, wherein said requested first PBS data comprises PBS data logged during a time period between a time instance when said first sending request was sent and a time instance when said SBS was turned on;

(9) accessing said primary PBS database storage, compressing said requested first PBS data, and sending said first requested compressed PBS data set to said SBS using said primary two-way communication link;

(10) matching said first logged SBS data with said first transmitted compressed PBS data set;

(11) computing an initial secondary base position (SBS_IP) relative to a primary base station position (PBS_P) by utilizing said first transmitted compressed PBS data set and said first logged matched SBS data;

(12) transmitting from said SBS to said rover initial data using said secondary communication link, wherein said initial data includes said SBS_P;

(13) sending a second request for a PBS data transfer by said SBS to said PBS, wherein said requested second PBS data comprises final PBS data logged during a final time period substantially sufficient to enable the computation of a final SBS_P (SBS_FP) with a required accuracy;

(14) accessing said primary PBS database storage, compressing said second requested logged PBS data, and sending said second compressed PBS data set to said SBS using said primary two-way communication link;

(15) computing said final secondary base position (SBS_FP) relative to a primary base station position (PBS_P) by using a post-processing technique;

(16) checking a plurality of statistical indicators to ensure a correct solution for said SBS_FP; and

(17) transmitting from said SBS to said rover a final data including said SBS_FP using said secondary communication link.

33. A method of RTK surveying comprising the steps of:

(1) setting up a primary base station (PBS) in a location having an known position;

(2) setting up a secondary base station (SBS) in a location having an unknown position, wherein said SBS location is set to provide a secondary communication link to a rover;

(3) starting said PBS to automatically log a first plurality of satellite observables at a first predetermined rate;

(4) storing said continuously logged PBS data in a primary database storage;

(5) starting said SBS to automatically log a second plurality of satellite observables at a second predetermined rate;

(6) storing said continuously logged SBS data in a secondary database storage;

(7) accessing said primary PBS database storage, compressing first PBS data, and sending said first compressed PBS data set to said SBS using a one-way primary communication link according to a predetermined schedule;

(8) matching said first logged SBS data with said first transmitted compressed PBS data set;

(9) computing an initial secondary base position (SBS_IP) relative to a primary base station position (PBS_P) by utilizing said first transmitted compressed PBS data and said first logged matched SBS data;

(10) transmitting from said SBS to said rover an initial data using said secondary communication link, wherein said initial data includes said SBS_IP;

(11) accessing said primary PBS database storage, compressing second logged PBS data, and sending said second compressed PBS data set to said SBS using said primary one-way communication link according to said predetermined schedule;

(12) computing said final secondary base position (SBS_FP) relative to a primary base station position (PBS_P) by using a post-processing technique;

(13) checking a plurality of statistical indicators to ensure a correct solution for said SBS_FP; and

(14) transmitting from said SBS to said rover final data including said SBS_FP using said secondary communication link.

34. A method for long baseline real time kinematic positioning (LBRTK) comprising the following steps:

(a) receiving a plurality of broadcast satellite signals by using a secondary base station (SBS) comprising a secondary base multi-frequency Satellite antenna;

(b) continuously obtaining a plurality of satellite observables using said plurality of received satellite signals by utilizing a secondary base satellite receiver;

(c) logging each said satellite observable obtained from said plurality of received satellite signals at a predetermined interval by utilizing a secondary base data storage;

(d) receiving primary base station (PBS) logged data using a primary data link;

(e) computing a secondary base position (SBS_P) relative to a primary base position (PBS_P) using said transmitted PBS data;

wherein said SBS_P relative to said PBS_P comprises a primary baseline; and

(f) transmitting to a rover said SBS_P data using a secondary data link between said SBS and said rover.

35. A method of RTK surveying comprising the steps of:

(1) setting up a secondary base station (SBS) in a location having an unknown position, wherein said SBS location is set to provide a secondary communication link to a rover;

(2) starting said SBS to automatically log a plurality of satellite observables at a predetermined rate;

(3) storing said continuously logged SBS data in a secondary database storage;

(4) initiating by said SBS a primary two-way communication link between said SBS and a primary base station (PBS);

(5) sending a request for a first PBS data transfer by said SBS to said PBS, wherein said requested first PBS data comprises PBS data logged during a time period between a time instance when said first sending request was sent and a time instance when said SBS was turned on;

(6) receiving said first requested PBS data from said SBS using said primary two-way communication link;

(7) matching said first logged SBS data with said first transmitted PBS data;

(8) computing an initial secondary base position (SBS_P) relative to a primary base station position (SBS_P) by utilizing said first transmitted PBS data and said first logged matched SBS data;

(9) transmitting from said SBS to said rover an initial data set using said secondary communication link, wherein said initial data includes said SBS_IP;

(10) sending a second request for PBS data transfer by said SBS to said PBS, wherein said requested second PBS data comprises a final PBS data set logged during a final time period substantially sufficient to enable the computation of a final SBS_P (SBS_FP) with a required accuracy;

(11) receiving said second compressed PBS data set from said SBS using said primary two-way communication link;

(12) computing said final secondary base position (SBS_FP) relative to a primary base station position (PBS_P) by using a post-processing technique;

(13) checking a plurality of statistical indicators to ensure a correct solution for said SBS_FP; and

(14) transmitting from said SBS to said rover a final data set including said SBS_FP using said secondary communication link.

36. A method of RTK surveying comprising the steps of:

(1) setting up a secondary base station (SBS) in a location having an unknown position, wherein said SBS location is set to provide a secondary communication link to a rover;

(2) starting said SBS to automatically log a plurality of satellite observables at a predetermined rate;

(3) storing said continuously logged SBS data in a secondary database storage;

(4) receiving a first PBS data set from said SBS using a primary one-way communication link according to a predetermined schedule;

(5) matching said first logged SBS data with said first transmitted PBS data;

(6) computing an initial secondary base position (SBS_IP) relative to a primary base station position (PBS_P) by utilizing said first transmitted PBS data and said first logged matched SBS data;

(7) transmitting from said SBS to said rover initial data using said secondary communication link, wherein said initial data includes said SBS_IP;

(8) receiving a second PBS data set from said SBS using said primary one-way communication link according to said predetermined schedule, wherein said second PBS data comprises final PBS data logged during a final time period substantially sufficient to enable the computation of a final SBS_P (SBS_FP) with a required accuracy;

(9) computing said final secondary base position (SBS_FP) relative to a primary base station position (PBS_P) by using a post-processing technique;

(10) checking a plurality of statistical indicators to ensure a correct solution for said SBS_P; and

(11) transmitting from said SBS to said rover final data including said SBS_FP using said secondary communication link.