Radiation-hardened fast acquisition/weak signal tracking system and method

• US 7,548,199 B2
• Filed: 09/20/2005
• Issued: 06/16/2009
• Est. Priority Date: 09/20/2004
• Status: Active Grant

• Current Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Original Assignee: United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration
• Inventors: Sirotzky, Steve, Winternitz, Luke, Boegner, Gregory J.
• Primary Examiner(s): Tarcza; Thomas H
• Assistant Examiner(s): Mull; Fred H
• Application Number:
  US11/239,458
• Publication Number:
  US 20060082496A1
• Time in Patent Office: 1,365 Days
• Field of Search: 342/357.06, 342/357.12, 342/357.15
• US Class Current: 342/357.63
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 19/29 carrier including Doppler, related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain

Abstract

A global positioning system (GPS) receiver and method of acquiring and tracking GPS signals comprises an antenna adapted to receive GPS signals; an analog radio frequency device operatively connected to the antenna and adapted to convert the GPS signals from an analog format to a digital format; a plurality of GPS signal tracking correlators operatively connected to the analog RF device; a GPS signal acquisition component operatively connected to the analog RF device and the plurality of GPS signal tracking correlators, wherein the GPS signal acquisition component is adapted to calculate a maximum vector on a databit correlation grid; and a microprocessor operatively connected to the plurality of GPS signal tracking correlators and the GPS signal acquisition component, wherein the microprocessor is adapted to compare the maximum vector with a predetermined correlation threshold to allow the GPS signal to be fully acquired and tracked.

Claims

1. A global positioning system (GPS) receiver comprising:

a GPS signal acquisition component comprising a frequency domain correlation module,

wherein said GPS signal acquisition component is adapted to acquire a GPS signal by receiving data from said GPS signal and processing said data to detect said GPS signal within one second for GPS signals with an EIRP of at least −

160 dBW, and

wherein said GPS receiver is adapted to operate in a space environment.

2. The GPS receiver of claim 1, further comprising:

a plurality of GPS signal tracking correlators adapted to track said GPS signals with an EIRP of at least −

175 dBW.

3. The GPS receiver of claim 1, wherein said GPS signal tracking correlators comprise a field-programmable gate array (FPGA).

4. The GPS receiver of claim 1, wherein said GPS signal acquisition component comprises a field-programmable gate array (FPGA).

5. The GPS receiver of claim 1, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one minute for GPS signals with an EIRP of at least −

180 dBW.

6. The GPS receiver of claim 1, wherein said GPS signal acquisition component is adapted to perform a Fast Fourier Transform (FFT) correlation process on said GPS signals.

7. The GPS receiver of claim 1, wherein said GPS signal acquisition component is adapted to acquire a GPS signal without a priori data for GPS signals with an EIRP of at least −

180 dBW.

8. A global positioning system (GPS) receiver comprising:

a GPS signal acquisition component comprising a frequency domain correlation module,

wherein said GPS signal acquisition component is adapted to acquire said GPS signals with an EIRP of at or below −

180 dBW without a priori data, and

wherein the acquired GPS signal is acquired by receiving data from said GPS signal and processing said data to detect said GPS signal substantially in real time.

9. The GPS receiver of claim 8, further comprising:

a plurality of GPS signal tracking correlators adapted to track said GPS signals with an EIRP of at least −

175 dBW.

10. The GPS receiver of claim 9, wherein said GPS signal tracking correlators comprising a field-programmable gate array (FPGA).

11. The GPS receiver of claim 8, wherein said GPS signal acquisition component comprises a field-programmable gate array (FPGA).

12. The GPS receiver of claim 8, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one minute for GPS signals with an EIRP of at least −

180 dBW.

13. The GPS receiver of claim 8, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one second for GPS signals with an EIRP of at least −

160 dBW.

14. The GPS receiver of claim 8, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one minute for GPS signals with an EIRP of at least −

180 dBW, and to acquire a GPS signal within one second for GPS signals with an EIRP of at least −

160 dBW.

15. The GPS receiver of claim 8, wherein said GPS signal acquisition component is adapted to perform a Fast Fourier Transform (FFT) correlation process on said GPS signals.

16. A global positioning system (GPS) receiver comprising:

a GPS signal acquisition component comprising a frequency domain correlation module,

wherein said GPS signal acquisition component is adapted to acquire said GPS signals with an EIRP of at or below −

160 dBW without a priori data, and

wherein the acquired GPS signal is acquired by receiving data from said GPS signal and processing said data to detect said GPS signal substantially in real time.

17. The GPS receiver of claim 16, further comprising:

a plurality of GPS signal tracking correlators adapted to track said GPS signals with an EIRP of at least −

175 dBW.

18. The GPS receiver of claim 17, wherein said GPS signal tracking correlators comprising a field-programmable gate array (FPGA).

19. The GPS receiver of claim 16, wherein said GPS signal acquisition component comprises a field-programmable gate array (FPGA).

20. The GPS receiver of claim 16, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one minute for GPS signals with an EIRP as low as −

180 dBW.

21. The GPS receiver of claim 16, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one second for GPS signals with an EIRP of at least −

160 dBW.

22. The GPS receiver of claim 16, wherein said GPS signal acquisition component is adapted to acquire a GPS signal within one minute for GPS signals with an EIRP of at least −

180 dBW, and to acquire a GPS signal within one second for GPS signals with an EIRP of at least −

160 dBW.

23. The GPS receiver of claim 16, wherein said GPS signal acquisition component is adapted to perform a Fast Fourier Transform (FFT) correlation process on said GPS signals.

24. A method of acquiring global positioning system (GPS) signals, said method comprising the steps:

receiving GPS signals;

performing a frequency domain correlation process on said GPS signals;

comparing the correlated GPS signals with a predetermined threshold and acquiring a GPS signal if a correlated GPS signal exceeds the predetermined threshold;

wherein said steps of acquiring said GPS signals are performed within one minute for GPS signals as low as −

180 dBW.

25. The method of claims 24, wherein said steps of acquiring said (GPS) signals are performed within one second for GPS signals as low as −

160 dBW.

26. The method of claim 24, further comprising acquiring said GPS signal without a priori data.