Method and apparatus for a GPS receiver capable or reception of GPS signals and binary offset carrier signals

• US 7,994,977 B2
• Filed: 12/02/2008
• Issued: 08/09/2011
• Est. Priority Date: 12/02/2008
• Status: Expired due to Fees

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: SIRF Technology Incorporated (Qualcomm, Inc.)
• Inventors: Lennen, Gary
• Primary Examiner(s): PHAN, DAO LINDA
• Application Number:
  US12/326,879
• Publication Number:
  US 20100134354A1
• Time in Patent Office: 980 Days
• Field of Search: 342/357.21, 342/357.26, 342/357.37, 342/357.46, 342/357.73, 342/357.77, 701/213, 701/215
• US Class Current: 342/357.77
• CPC Class Codes: G01S 19/33 Multimode operation in different systems which transmit time stamped messages, e.g. GPS/GLONASS

Abstract

A system and method capable of mitigating the migration from the current GPS system to the Galileo system and allow a single satellite system positioning receiver to process both GPS signals and Galileo signals.

Claims

1. A global positioning system (GPS) and Galileo system device, comprising:

an input sample memory for receipt of 4fo digital signal samples of a positioning signal in a first mode or 16fo digital signal samples from a digital mixer in a second mode;

a carrier generator for generation a 1023 chip spreading code when 4fo digital signal samples of a GPS signals are received and 4092 chip spreading code when 16fo digital signal samples of a Galileo signal are received;

a match filter configurable for at least a ½

chip and ¼

chip match filter that match the spreading code with the digital samples from the digital sample memory;

a coherent memory to store the filtered data from the match filter;

a non-coherent memory for storage of non-coherent data that results from application of a fast Fourier transform to the filtered data; and

a peak detector that detects data peaks by sorting the non-coherent data in the non-coherent memory and storing the detected peaks in a peak memory, where the peaks indicate the presence of a signal from a satellite vehicle.

2. The GPS and Galileo system device of claim 1, further comprising a binary offset carrier (BOC) signal as the positioning signal received at the digital mixer when the device is in the second mode.

3. The GPS and Galileo system device of claim 2, where the match filter as a ¼

chip match filter.

4. The GPS and Galileo system device of claim 2, where the coherent memory is larger in the second mode relative to the first mode.

5. The GPS and Galileo system device of claim 2, where the non-coherent memory is larger in the second mode relative to the first mode.

6. The GPS and Galileo system device of claim 2, where the satellite vehicle is a Galileo satellite.

7. The GPS and Galileo system device of claim 2, including:

a 3fo carrier mixed with the 16fo digital samples by the digital mixer resulting in a digital samples that are stored in the input sample memory;

a short code generator that generates a portion of a spreading code that is used by the ½

chip match filter to generate filtered data that is stored in the coherent memory during acquisition of a side lobe of a Galileo positioning signal.

8. The GPS and Galileo system device of claim 7, further including a 5fo carrier mixed with the 16fo digital samples by the digital mixer resulting both digital samples stored in a 3fo input sample memory and a 5fo input sample memory that is further processed by the matched filter resulting in filtered data stored in the coherent memory during acquisition of both side lobes of a Galileo position signal.

9. The GPS and Galileo system device of claim 2, including:

a 5fo carrier mixed with the 16fo digital samples by the digital mixer resulting in a digital samples that are stored in the input sample memory;

a short code generator that generates a portion of a spreading code that is used by the ½

chip match filter to generate filtered data that is stored in the coherent memory during acquisition of a side lobe of a Galileo positioning signal.

10. The GPS and Galileo system device of claim 9, further including a 3fo carrier mixed with the 16fo digital samples by the digital mixer resulting both digital samples stored in a 3fo input sample memory and a 5fo input sample memory that is further processed by the matched filter resulting in filtered data stored in the coherent memory during acquisition of both side lobes of a Galileo position signal.

11. The GPS and Galileo system device of claim 1, further including,

a start mode with the input sample memory adapted to store input samples from a GPS positioning signal that are processed by the match filter that employs a GPS dispreading code in determining if a GPS satellite vehicle has been acquired and the match filter being configured to process input samples from a BOC signal in response to acquisition of the GPS satellite.