SOFTWARE-BASED SPREAD SPECTRUM SIGNAL PROCESSING

• US 20090257525A1
• Filed: 06/22/2006
• Published: 10/15/2009
• Est. Priority Date: 06/22/2006
• Status: Active Grant

• Current Assignee: Qualcomm technologies international, ltd. (Qualcomm, Inc.)
• Original Assignee: Nodrdnav Technologies AB
• Inventors: Stahlberg, Christian, Normark, Per-Ludvig, Mitelman, Alexander Michael
• Granted Patent: US 8,270,529 B2
• Time in Patent Office: Days
• US Class Current: 375/296
• CPC Class Codes: G01S 19/24 Acquisition or tracking or demodulation of signals transmitted by the system synchronisation aspects of direct sequence spread spectrum modulation H04B1/7073
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain
• CPC Class Codes: G06F 9/505 considering the load
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 2201/70707 Efficiency-related aspects
• CPC Class Codes: H04B 2201/7071 with dynamic control of receiver resources
• CPC Class Codes: H04B 2201/70715 with application-specific features
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A proposed data processing device includes at least two processor units, which each is adapted to process digitized precorrelation navigation satellite signal data as well as to process alternative data and/or signals relating to at least one function being uncorrelated with the satellite signal data. The device includes at least one data buffer adapted to store data sets, where each set includes a number of instances of the satellite signal data. A control module in the device controls execution of a processing job with respect to a stored data set by allocating individual processing tasks to at least one of the at least two processor units based on a current processing load on each processor unit.

Claims

1. A data processing device adapted to process digitized precorrelation navigation satellite signal data (d_F), and to process alternative data and/or signals (D_A) relating to at least one function being uncorrelated with said satellite signal data (d_F), the device (100) comprises:

at least two processor units (141, 142, 143) which each is adapted to process said satellite signal data (d_F) and to process the alternative data and/or signals (D_A),

at least one data buffer (131, 132) adapted to store data sets ([d_F]), each set including a number of instances of said satellite signal data (d_F), and

a control module (150) adapted to control execution of a processing job involving producing target data (D₁, D₂, D₃) based on a data set ([d_F]) stored in at least one of the at least one data buffer (131, 132) by allocating individual processing tasks to at least one of the at least two processor units (141, 142, 143) based on a current processing load on each processor unit (141, 142;

143).

2. The device (100) according to claim 1, wherein the control module (150) is adapted to allocate the individual processing tasks to at least one of the at least two processor units (141, 142, 143) further based on a type of processing to be executed relative to a performance profile of the respective processor unit.

3. The device (100) according to claim 1, wherein the control module (150) is adapted to allocate the individual processing tasks to at least one of the at least two processor units (141, 142, 143) further based on an amount of processing to be executed with respect to the data set ([d_F]).

4. The device (100) according to claim 1, wherein the control module (150) is adapted to allocate the individual processing tasks to at least one of the at least two processor units (141, 142, 143) further based on a time frame within which the processing job is to be completed.

5. The device (100) according to claim 1, wherein the control module (150) is adapted to allocate the individual processing tasks to the at least one of the at least two processor units (141, 142, 143) based on an allowed utilization of the respective processor unit, the allowed utilization specifying a measure of resources being potentially available for satellite signal processing.

6. The device (100) according to claim 1, wherein each of the at least two processor units (141, 142, 143) is adapted to produce a set of target data (D₁, D₂, D₃) resulting from a respective processing task completed by the unit.

7. The device (100) according to claim 1, wherein each of the at least two processor units (141, 142, 143) is adapted to transmit a status signal (s₁, s₂, s₃) to the control module (150), the status signals (s₁, s₂, s₃) reflecting a respective load status for the processor unit (141, 142, 143), and the control module (150) is adapted to allocate said processing tasks based on the status signals (s₁, s₂, s₃).

8. The device (100) according to claim 1, wherein each of the at least two processor units (141, 142, 143) is adapted to receive a task specification defining a respective processing task to be executed by the unit.

9. The device (100) according to claim 8, claim 1 wherein the task specification includes at least one entry specifying at least one of:

a number of processing iterations to be completed with respect to the data set ([d_F]), at least one signal source identity, a type of processing to be performed and a time requirement for the processing task.

10. The device (100) according to claim 8 wherein each of the at least two processor units (141, 142, 143) is associated with a programmable module (c₁, c₂, c₃) adapted to store the task specification.

11. The device (100) according to claim 10, wherein the processing job involves performing operations according to a first type of arithmetic, at least one of the at least two processor units (141, 142, 143) is adapted to perform computations based on a second type of arithmetic, and each of said programmable modules (c₁, c₂, c₃) being associated with said at least two processor units (141, 142, 143) is adapted to store an instruction set adapted to convert a processing task from a first type of task defined in the first type of arithmetic to an equivalent task defined in the second type of arithmetic.

12. The device (100) according to claim 1, wherein at least one of the at least two processor units (141, 142, 143) is represented by a central processing unit.

13. The device (100) according to claim 12, wherein the control module (150) is implemented in software.

14. The device (100) according to claim 12 wherein the control module (150) is included in one of the at least two processor units (141, 142, 143).

15. The device (100) according to claim 14, wherein the control module (150) is included in a central processing unit.

16. The device (100) according to claim 1, wherein at least one of the at least two processor units (141, 142, 143) is represented by at least one of a digital signal processing, a graphics processing unit, a vector processor unit, a media processing unit, an audio processing unit, a floating-point processing unit and an accelerator unit.

17. A method of processing digitized precorrelation navigation satellite signal data (d_F), and alternative data and/or signals (D_A) relating to at least one function being uncorrelated with said satellite signal data (d_F), the method comprising:

investigating whether or not at least one of the alternative data and/or signals (D_A) is present, and if so processing the alternative data and/or signals (D_A), investigating whether or not positioning related processing is to be performed, and if so receiving the satellite signal data (d_F), and

storing the satellite signal data (d_F) in at least one data buffer (131, 132) in the form of a data set ([d_F]), the data set ([d_F]) including a number of instances of said satellite signal data (d_F), characterized by the method involving production of target data (D₁, D₂, D₃) based on a data set ([d_F]) stored in at least one of the at least one data buffer (131, 132) by using at least two processor units (141, 142, 143), the method comprising allocating individual processing tasks of a processing job to at least one of the at least two processor units (141, 142, 143) based on a current processing load on each processor unit (141, 142;

143).

18. The method according to claim 17 further comprising allocating individual processing tasks of a processing job to at least one of the at least two processor units (141, 142, 143) further based on a type of processing to be executed relative to a performance profile of the respective processor unit.

19. The method according to claim 17 further comprising allocating individual processing tasks of a processing job to at least one of the at least two processor units (141, 142, 143) further based on an amount of processing to be executed with respect to the data set ([d_F]).

20. The method according to claim 17 further comprising allocating individual processing tasks of a processing job to at least one of the at least two processor units, (141, 142, 143) further based on a time frame within which the processing job is to be completed.

21. The method according to claim 17 further comprising repeating the task allocation step at a repetition rate being determined by at least one of a size of the data set ([d_F]), the type of processing to be executed, a clock frequency used by the at least two processor units (141, 142, 143), and spectral characteristics of received satellite signals (S_BL) from which the satellite signal data (d_F) is derived.

22. The method according to a claim 17 further comprising allocating the individual processing tasks to the at least one of the at least two processor units (141, 142, 143) based on an allowed utilization of the respective processor unit, the allowed utilization specifying a measure of resources being potentially available for satellite signal processing.

23. The method according to claim 17 further comprising producing, in each of the at least two processor units (141, 142, 143), a set of target data (D₁, D₂, D₃) resulting from a respective processing task completed by the unit.

24. The method according to claim 17 further comprising providing a control module (150) with status signals (s₁, s₂, s₃) reflecting a respective load status for each of the at least two processor units (141, 142, 143), the control module (150) being adapted to allocate said processing tasks based on the status signals (s₁, s₂, s₃).

25. The method according to claim 17 further comprising forwarding a task specification to each of the at least two processor units (141, 142, 143), the task specification defining a respective processing task to be executed by the unit.

26. The method according to claim 25, further comprising a programmable module (c₁, c₂, c₃) being associated with each of the at least two processor units (141, 142, 143), and the method comprising storing a respective task specification in at least one of said programmable modules (c₁, c₂, c₃).

27. The method according to claim 26, further comprising characterized by the processing job involving performing operations according to a first type of arithmetic, at least one of the at least one processor units (141, 142, 143) being adapted to perform computations based on a second type of arithmetic, and each of said programmable modules (c₁, c₂, c₃) being associated with said at least one processor unit (141, 142, 143) storing an instruction set adapted to convert a processing task from a first type of task defined in the first type of arithmetic to an equivalent task defined in the second type of arithmetic.

28. A computer program product directly loadable into the memory of a computer, comprising software for controlling the steps of claim 17 when said program is run on the computer.

29. A computer readable medium (155), having a program recorded thereon, where the program is to make a computer control the steps of claim 17.