Integrated pseudolite/satellite base station transmitter

• US 6,473,033 B1
• Filed: 03/18/2001
• Issued: 10/29/2002
• Est. Priority Date: 03/18/2001
• Status: Expired due to Term

• Current Assignee: Trimble Navigation Limited (Trimble Inc.)
• Original Assignee: Trimble Navigation Limited (Trimble Inc.)
• Inventors: Trimble, Charles R.
• Primary Examiner(s): Blum, Theodore M.
• Application Number:
  US09/812,011
• Time in Patent Office: 590 Days
• Field of Search: 342/357.14, 342/357.06, 701/213
• US Class Current: 342/357.395
• CPC Class Codes: G01S 19/04 providing carrier phase data
• CPC Class Codes: G01S 19/071 DGPS corrections
• CPC Class Codes: G01S 19/08 providing integrity information, e.g. health of satellites or quality of ephemeris data
• CPC Class Codes: G01S 19/11 wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters

Abstract

An integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter comprising a satellite base station and a split-spectrum pseudolite (SS-PL) transmitter co-located with the satellite base station. The satellite base station provides a timing synchronization signal. The satellite base station also provides a self-surveying capability for the split-spectrum pseudolite (SS-PL). The split-spectrum pseudolite (SS-PL) generates a split-spectrum sideband signal that minimizes interference with the reception of at least one satellite signal by the satellite base station.

Claims

1. An integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter comprising:

a satellite base station;

a split-spectrum pseudolite (SS-PL) transmitter co-located with said satellite base station; and

a connection line between said satellite base station and said (SS-PL) transmitter;

wherein said satellite base station provides a timing synchronization signal;

and wherein said satellite base station provides a self-surveying capability for said split-spectrum pseudolite (SS-PL);

and wherein said connection line is used to transmit synchronously a set of satellite data from said satellite base station to said (SS-PL) transmitter;

and wherein said integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter transmits a message including said synchronized satellite data.

2. The integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter of claim 1, wherein said satellite base station further comprises:

a differential GPS base station configured to provide a GPS timing synchronization signal to said SS-PL pseudolite transmitter, and configured to provide said self-surveying capability for said split-spectrum pseudolite (SS-PL) with a sub-meter accuracy.

3. The integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter of claim 1, wherein said satellite base station further comprises:

an RTK GPS base station configured to provide a GPS timing synchronization signal to said split-spectrum (SS-PL) transmitter, and configured to provide said self-surveying capability for said split-spectrum pseudolite (SS-PL) with a centimeter accuracy.

4. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3, wherein said (SS-PL)/RTK GPS base station transmitter is configured to transmit position determining split-spectrum L1 GPS signals, and wherein said (SS-PL)/RTK GPS base station transmitter further comprises:

a code generator for generating a pseudolite P-code, wherein said pseudolite P-code is delayed as compared with a GPS P-code by a delay D; and

wherein said delay D is used to identify said integrated split-spectrum pseudolite/satellite base station (SS-PL)/RTK GPS base station transmitter as a (SS-PL)/RTK GPS_D transmitter having said D number;

a modulator coupled to said code generator for modulating said code and said GPS navigation data to produce a modulated split-spectrum sideband L1 signal;

a means for receiving a GPS satellite synchronization signal and for receiving a plurality of exact GPS satellite frequencies; and

a means for generating a set of (SS-PL) data message responsive to a set of formatted GPS navigation data;

wherein said set of (SS-PL) data message has a substantial capacity required to support said at least one GPS integrity update and at least one (SS-PL) integrity update; and

wherein said set of (SS-PL) data message has a substantial capacity required to support a set of DGPS corrections for code and carrier at a substantially high data rate; and

wherein said set of (SS-PL) data message includes a set of said (SS-PL) positional data.

5. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 4, wherein said means for receiving a GPS satellite synchronization signal and for receiving a plurality of exact GPS satellite frequencies further includes:

a GPS receiver.

6. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3, wherein said (SS-PL)/RTK GPS base station transmitter is configured to transmit position determining split-spectrum L2 GPS signals, and wherein said (SS-PL)/RTK GPS base station transmitter further comprises:

a code generator for generating a pseudolite P-code, wherein said pseudolite P-code is delayed as compared with a GPS P-code by a delay D; and

wherein said delay D is used to identify said integrated split-spectrum pseudolite/satellite base station (SS-PL)/RTK GPS base station transmitter as a (SS-PL)/RTK GPS_D transmitter having said D number;

a modulator coupled to said code generator for modulating said code and said GPS navigation data to produce a modulated split-spectrum sideband L2 signal;

a means for receiving a GPS satellite synchronization signal and for receiving a plurality of exact GPS satellite frequencies; and

a means for generating a set of (SS-PL) data message responsive to a set of formatted GPS navigation data;

wherein said set of (SS-PL) data message has a substantial capacity required to support said at least one GPS integrity update and at least one (SS-PL) integrity update; and

wherein said set of (SS-PL) data message has a substantial capacity required to support a set of DGPS corrections for code and carrier at a substantially high data rate; and

wherein said set of (SS-PL) data message includes a set of said (SS-PL) positional data.

7. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 6, wherein said means for receiving a GPS satellite synchronization signal and for receiving a plurality of exact GPS satellite frequencies further includes:

a GPS receiver.

8. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3, wherein said (SS-PL)/RTK GPS base station transmitter is configured to transmit position determining split-spectrum L5 GPS signals, and wherein said (SS-PL)/RTK GPS base station transmitter further comprises:

a code generator for generating a pseudolite P-code, wherein said pseudolite P-code is delayed as compared with a GPS P-code by a delay D; and

wherein said delay D is used to identify said integrated split-spectrum pseudolite/satellite base station (SS-PL)/RTK GPS base station transmitter as a (SS-PL)/RTK GPS_D transmitter having said D number;

a modulator coupled to said code generator for modulating said code and said GPS navigation data to produce a modulated split-spectrum sideband L5 signal;

a means for receiving a GPS satellite synchronization signal and for receiving a plurality of exact GPS satellite frequencies; and

a means for generating a set of (SS-PL) data message responsive to a set of formatted GPS navigation data;

wherein said set of (SS-PL) data message has a substantial capacity required to support said at least one GPS integrity update and at least one (SS-PL) integrity update; and

wherein said set of (SS-PL) data message has a substantial capacity required to support a set of DGPS corrections for code and carrier at a substantially high data rate; and

wherein said set of (SS-PL) data message includes a set of said (SS-PL) positional data.

9. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 8, wherein said means for receiving a GPS satellite synchronization signal and for receiving a plurality of exact GPS satellite frequencies further includes:

a GPS receiver.

10. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3 further including:

a radio receiver for receiving a set of GPS formatted navigational data.

11. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3 further including:

a signal generator for generating a standard reference frequency.

12. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 4 further including:

a pseudolite antenna coupled to said modulator for transmitting said position determining sideband L1 split-spectrum signal.

13. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 6 further including:

a pseudolite antenna coupled to said modulator for transmitting said position determining sideband L2 split-spectrum signal.

14. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 8 further including:

a pseudolite antenna coupled to said modulator for transmitting said position determining sideband L5 split-spectrum signal.

15. The integrated split-spectrum pseudolite (SS-PL)RTK GPS base station transmitter of claim 3 further including:

a means for detecting at least one integrated split-spectrum pseudolite (SS-PL) RTK GPS_D1 transmitter having a D1 delay number.

16. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 15, wherein said means for detecting said at least one integrated split-spectrum pseudolite (SS-PL)/RTK GPS_D1 transmitter having said D1 delay number further includes:

a GPS receiver.

17. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3 further including:

a code selection control means associated with said RTK GPS base station for selecting a type of code to be used in said split-spectrum sideband signal.

18. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3 further including:

a time sequence control means associated with said RTK GPS base station for determining a time sequence used for transmitting said split-spectrum sideband signal.

19. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 3 further including:

a split-spectrum pseudolite clock synchronized with said GPS timing synchronization signal for generating a plurality of split-spectrum pseudolite clock signals.

20. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 10 further comprising:

a data storage device coupled to said radio receiver, wherein said data storage device is configured to store a set of GPS navigation data.

21. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 4, wherein said code generator further comprises:

a code generator configured for generating a pseudolite P-code delayed by at least one minute as compared with said GPS P-code; and

wherein said minimum delay D=1 min is used to identify said integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter as a (SS-PL)/RTK GPS_D=N transmitter having said D={N multiplied by one-minute delay} number, N being an integer.

22. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 4, wherein said modulator is configured to modulate said code and said GPS navigation data to produce a modulated split-spectrum sideband L1 signal having a peak power at frequencies at which P(Y) code has nulls.

23. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 6, wherein said modulator is configured to modulate said code and said GPS navigation data to produce a modulated split-spectrum sideband L2 signal having a peak power at frequencies at which P(Y) code has nulls.

24. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 8, wherein said modulator is configured to modulate said code and said GPS navigation data to produce a modulated split-spectrum sideband L5 signal having a peak power at frequencies at which P(Y) code has nulls.

25. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 4, wherein said modulator is configured to modulate said code and said GPS navigation data to produce a modulated split-spectrum sideband (L1∓

Δ

1) MHz signal having a frequency shift Δ

1 and having a peak power at frequencies at which P(Y) code has nulls, wherein said frequency shift Δ

1 determines how far a signal noise is removed from the center frequency L1.

26. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 25, wherein said frequency shift Δ

1 is equal to K1 multiplied by 10.23 MHz, K1 being an integer.

27. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 6, wherein said modulator is configured to modulate said code and said GPS navigation data to produce a modulated split-spectrum sideband (L2∓

Δ

2) MHz signal having a frequency shift Δ and

having a peak power at frequencies at which P(Y) code has nulls, wherein said frequency shift Δ

2 determines how far a signal noise is removed from the center frequency L2.

28. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 27, wherein said frequency shift Δ

2 is equal to K2 multiplied by 10.23 MHz, K2 being an integer.

29. The integrated split-spectrum pseudolite (SS-PL)/RTK GPS base station transmitter of claim 8, wherein said modulator is configured to modulate said code and said GPS navigation data to produce a modulated split-spectrum sideband (L5∓

Δ

5) MHz signal having a frequency shift Δ

5 and having a peak power at frequencies at which P(Y) code has nulls, wherein said frequency shift Δ

5 determines how far a signal noise is removed from the center frequency L5.

30. A method of generating a split-spectrum sideband signal by an integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D transmitter having a delay D identification number;

said method comprising the steps of;

providing a timing synchronization signal by said satellite base station;

providing a self-surveying capability for said split-spectrum pseudolite (SS-PL) by said satellite base station;

using a connection line to transmit synchronously a set of satellite data from said satellite base station to said (SS-PL) transmitter;

generating a split-spectrum sideband signal by said integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D transmitter; and

using said integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter to transmit a message including said synchronized satellite data;

wherein said split-spectrum sideband signal includes a set of position coordinates for said integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D transmitter having said delay D identification number.

31. The method of claim 30 further including the step of:

detecting at least one additional active split spectrum sideband signal generated by at least one additional intergrated split-spectrum pseudolite/satellite base (SS-PL)/GPS_D1 transmitter having a delay D1 identification number.

32. The method of claim 31 further including the steps of:

determining a set of coordinates for each said active integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D* transmitter having a delay D* identification number;

matching each said set of coordinates with one said integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D* transmitter; and

creating a database including a set of coordinates and an identification number D* for each said active integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D* transmitter.

33. The method of claim 32 further including the steps of:

broadcasting a message including said database including said set of coordinates and said identification number D* for each said active integrated split-spectrum pseudolite/satellite base station (SS-PL)/GPS_D* transmitter.

34. An integrated split-spectrum pseudolite/satellite base station (SS-PL)/SBS transmitter comprising:

a means for providing a timing satellite synchronization signal;

a means for providing a surveying capability for said split-spectrum pseudolite (SS-PL); and

a means for generating a split-spectrum sideband signal;

wherein said means for providing said timing satellite synchronization signal and said means for providing said surveying capability for said split-spectrum pseudolite (SS-PL) are linked to said means for generating said split-spectrum sideband signal.