Address translation logic for use in a GPS receiver

• US 7,065,629 B2
• Filed: 11/18/2002
• Issued: 06/20/2006
• Est. Priority Date: 11/18/2002
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: RF Micro Devices Incorporated (Qorvo, Inc.)
• Inventors: Warloe, Andreas, Field, Michael J.
• Primary Examiner(s): Verbrugge, Kevin
• Assistant Examiner(s): Namazi, Mehdi
• Application Number:
  US10/298,983
• Publication Number:
  US 20040098558A1
• Time in Patent Office: 1,310 Days
• Field of Search: 711/202, 708/422, 455/78, 342/357.09, 342/357.12, 342/130
• US Class Current: 711/202
• CPC Class Codes: G01S 19/21 Interference related issues ; Issues related to cross-correlation, spoofing or other methods of denial of service
• 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

The address translation logic of the present invention is incorporated in a global positioning system (GPS) receiver and operates to group data in memory based on translating the address from a direct memory access controller. The data includes post-correlated samples of the correlation of a signal with a generated frequency and a generated code having a plurality of time offsets. In general, the address translation logic organizes the data such that each element of the data associated with particular ones of the plurality of time offsets are grouped together in order to improve the efficiency of performing a fast Fourier transform of the data. In addition, the address translation logic allows the transfer of data from correlation circuitry to memory, from the memory to an FFT module, and from the FFT module to the memory using standard DMA controllers.

Claims

1. A GPS receiver comprising:

address translation logic adapted to provide a plurality of translated addresses each based on an address from memory access logic;

said memory access logic adapted to provide each said address to said address translation logic;

memory adapted to store data in a plurality of memory locations corresponding to said plurality of translated addresses; and

circuitry adapted to provide said data to said memory based on a signal received by the GPS receiver, wherein said data comprises a plurality of subsets each having a plurality of data elements;

wherein said address translation logic provides said plurality of translated addresses based on organizing said data such that each of said plurality of data elements associated with each of said plurality of subsets are grouped together in said memory, each of said plurality of subsets corresponds to results of a correlation of said signal with a generated frequency and a generated code at a one of a plurality of time offsets, and each of said plurality of data elements in each of said plurality of subsets corresponds to a partial correlation sample from a time limited accumulation of data from the results of the correlation of said signal with said generated frequency and said generated code at said one of said plurality of time offsets.

2. A GPS receiver comprising:

circuitry adapted to provide a serial data stream comprising a plurality of subsets each comprising a plurality of data elements based on a signal received by the GPS receiver;

memory adapted to receive said serial data stream and store said plurality of data elements for each of said plurality of subsets based on a plurality of translated addresses;

memory access logic adapted to provide a plurality of sequential addresses; and

address translation logic adapted to translate said plurality of sequential addresses into said plurality of translated addresses such that, for each of said plurality of subsets, said plurality of data elements for said subset are grouped together in said memory.

3. The GPS receiver of claim 2 further comprising transform circuitry adapted to obtain said plurality of data elements for each of said plurality of subsets and transform said plurality of data elements for each of said plurality of subsets into a frequency domain to produce transformed data.

4. The GPS receiver of claim 2 wherein said circuitry comprises a plurality of correlators each providing said plurality of data elements for a one of said plurality of subsets based on said signal.

5. The GPS receiver of claim 2 wherein said circuitry is further adapted to provide said serial data stream by multiplexing said plurality of subsets.

6. The GPS receiver of claim 2 wherein each of said plurality of subsets corresponds to results of a correlation of said signal with a generated frequency and a generated code at a one of a plurality of time offsets.

7. The GPS receiver of claim 6 wherein each of said plurality of data elements in each of said plurality of subsets corresponds to a partial correlation sample from a time limited accumulation of said results of said correlation of said signal with said generated frequency and said generated code at said one of said plurality of time offsets.

8. The GPS receiver of claim 2 wherein said memory access logic comprises a direct memory access controller.

9. A GPS receiver comprising:

circuitry adapted to provide a serial data stream comprising a plurality of subsets each comprising a plurality of data elements based on a baseband signal;

memory adapted to receive said serial data stream and store said plurality of data elements for each of said plurality of subsets based on a plurality of translated addresses;

memory access logic adapted to provide a plurality of sequential addresses;

address translation logic adapted to translate said plurality of sequential addresses into said plurality of translated addresses such that, for each of said plurality of subsets, said plurality of data elements for said subset are grouped together in said memory; and

a receiver frontend adapted to receive a GPS signal and process the GPS signal to provide said baseband signal.

10. The GPS receiver of claim 9 further comprising transform circuitry adapted to obtain said plurality of data elements for each of said plurality of subsets and transform said plurality of data elements for each of said plurality of subsets into a frequency domain to produce transformed data.

11. The GPS receiver of claim 9 wherein said circuitry comprises a plurality of correlators each providing said plurality of data elements for a one of said plurality of subsets based on said baseband signal.

12. The GPS receiver of claim 9 wherein said circuitry is further adapted to provide said serial data stream by multiplexing said plurality of subsets.

13. The GPS receiver of claim 9 wherein each of said plurality of subsets corresponds to results oft correlation of said baseband signal with a generated frequency and a generated code at a one of a plurality of time offsets.

14. The GPS receiver of claim 9 wherein each of said plurality of data elements in each of said plurality of subsets corresponds to a partial correlation sample from a time limited accumulation of said results of said correlation of said baseband signal with said generated frequency and said generated code at said one of said plurality of time offsets.

15. The GPS receiver of claim 9 wherein said memory access logic comprises a direct memory access controller.

16. A GPS receiver comprising:

means for providing a serial data stream comprising a plurality of subsets each comprising a plurality of data elements based on a signal received by the GPS receiver;

means for storing said plurality of data elements for each of said plurality of subsets based on a plurality of translated addresses;

means for providing a plurality of sequential addresses; and

means for translating said plurality of sequential addresses into said plurality of translated addresses such that, for each of said plurality of subsets, said plurality of data elements for said subset are grouped together in said means for storing.

17. The GPS receiver of claim 16 further comprising means for obtaining said plurality of data elements for each of said plurality of subsets and transforming said plurality of data elements for each of said plurality of subsets into a frequency domain to produce transformed data.

18. The GPS receiver of claim 16 wherein said means for providing said serial data stream is further adapted to provide said serial data stream by multiplexing said plurality of subsets.

19. The GPS receiver of claim 16 wherein each of said plurality of subsets corresponds to results of a correlation of said signal with a generated frequency and a generated code at a one of a plurality of time offsets.

20. The GPS receiver of claim 19 wherein each of said plurality of data elements in each of said plurality of subsets corresponds to a partial correlation sample from a time limited accumulation of said results of said correlation of said signal with said generated frequency and said generated code at said one of said plurality of time offsets.