GPS BASEBAND CONTROLLER ARCHITECTURE

• US 20110102257A1
• Filed: 11/04/2010
• Published: 05/05/2011
• Est. Priority Date: 11/04/2009
• Status: Active Grant

• Current Assignee: Maxlinear Incorporated
• Original Assignee: Maxlinear Incorporated
• Inventors: Spyropoulos, Ioannis, Anandakumar, Anand, Rasse, Yves, Leclercq, Maxime
• Granted Patent: US 9,739,890 B2
• Time in Patent Office: Days
• US Class Current: 342/357.31
• CPC Class Codes: G01S 19/34 Power consumption

Abstract

A GPS receiver includes an RF front end for acquiring and tracking a satellite signal and a baseband processor configured to preserve power. The baseband processor includes a GPS engine configured to process the satellite signal and generate a PVT fix, a power supervisory module for receiving the PVT fix, and a user state module that determines an environmental state, wherein the power supervisory module may power down the GPS receiver for a period of time based on a result of the determined environment state. The baseband processor also includes a time-based management module that adjusts the TCXO in response to the determined environmental state. The GPS receiver includes a plurality of operation modes, each of which is associated with a plurality of tracking profiles.

Claims

1. A GPS receiver comprising an RF front end module configured to acquire and tracking a satellite signal and a baseband processor that in turn includes:

a GPS engine configured to process the satellite signal and generate a PVT fix;

a power supervisory module configured to receive the PVT fix; and

a user state module for determining an environmental state;

wherein the power supervisory module powers down the RF front end module and the GPS engine for a shut-down time period based on a result of the determined environment state.

2. The GPS receiver of claim 1, wherein the environmental state comprises an estimated velocity or an estimated acceleration.

3. The GPS receiver of claim 1 further comprising:

a PVT fix module coupled to the power supervisory module and being configured to;

process the PVT fix;

assign a position accuracy index to the processed PVT fix;

report the processed PVT fix to a host;

store the processed PVT fix in a memory; and

provide a feedback signal to the power supervisory module when the accuracy index falls within a target accuracy range.

4. The GPS receiver of claim 3, wherein the process the PVT fix comprises a sensor-assisted position filtering.

5. The GPS receiver of claim 1 further comprising a plurality of operation modes, each of the plurality of the operation modes is associated with a plurality of power profiles.

6. The GPS receiver of claim 5, wherein the plurality of operation modes comprises a tracking operation mode configured to provide the PVT fix to a host at a regular time interval.

7. The GPS receiver of claim 6, wherein the regular time interval comprises a programmable time duration.

8. The GPS receiver of claim 5, wherein the plurality of operation modes comprises a tracking operation mode configured to maintain hot start conditions.

9. The GPS receiver of claim 5, wherein the power supervisory module selects one of the plurality of the operation modes in response to an instruction received from a host.

10. The GPS receiver of claim 5, wherein the power supervisory module selects one of the plurality of the power profiles based on an adaptive algorithm configured to provide a trade-off between a position accuracy and time-to-fix for obtaining a minimum power consumption.

11. The GPS receiver of claim 5, wherein the plurality of power profiles comprises a continuous tracking profile, a low power continuous tracking profile, a background intermittent tracking profile, and a high-accuracy intermittent tracking profile.

12. The GPS receiver of claim 11, wherein the background tracking profile is associated with a deep sleep mode, in which the GPS receiver is powered down with an exception of a backup memory and while a 32 kHz RTC clock is calibrated for a calibrated time interval.

13. The GPS receiver of claim 12, wherein the GPS receiver uses the calibrated 32 kHz RTC clock for tracking upon waking up from the deep sleep mode.

14. The GPS receiver of claim 1 further comprising:

a time-base management module configured to ensure that a temperature-compensated crystal oscillator (TCXO) frequency is within an acceptable range for an operation of the GPS engine.

15. The GPS receiver of claim 14, wherein the TCXO frequency is interpolated based on the determined environmental state that includes a sensed temperature value.

16. The GPS receiver of claim 1, wherein the time period for power-down the GPS receiver is adjustable based on a user triggered event.

17. The GPS receiver of claim 1, wherein the time period for power-down the GPS receiver is adjustable based on the determined environmental state.

18. The GPS receiver of claim 1, wherein the user state module comprises a temperature sensing circuit.

19. The GPS receiver of claim 1, wherein the user state module comprises an accelerator sensing circuit.

20. A method of conserving power consumption in a GPS receiver having a plurality of modules, the method comprising:

receiving a start command from a host at a power supervisory module;

acquiring and tracking a GPS signal from a number of satellites to obtain a PVT fix;

processing the PVT fix;

assigning an accuracy index to the processed PVT fix; and

stop tracking when the accuracy index is within a target accuracy range.

21. The method of claim 20 further comprising:

reporting the processed PVT fix to the host at a regular time interval.

22. The method of claim 21, wherein the regular time interval is programmable.

23. The method of claim 20, wherein the accuracy index is characterized by a received signal strength of the GPS signal.

24. The method of claim 20, wherein the accuracy index is characterized by a position accuracy range.

25. The method of claim 20, wherein the stop tracking comprises power down the entire plurality of modules while calibrating a 32 kHz RTC.

26. The method of claim 20 further comprising:

storing the PVT fix in a memory.

27. The method of claim 20 further comprising:

providing a time interval to the power supervisory module for a next tracking.

28. A method of conserving power consumption in a GPS receiver having a plurality of modules, the method comprising:

receiving a start command from a host at a power supervisory module;

acquiring and tracking a GPS signal from a number of satellites to obtain a PVT fix;

providing the PVT fix to a user state module;

determining an environmental state at the user state module; and

powering down the plurality of modules for a time period in response to the determined environmental state.

29. The method of claim 28, wherein the environmental state comprises a temperature data.

30. The method of claim 28, wherein the environmental state comprises a velocity data.

31. The method of claim 28, wherein the time period is adjustable based on the determined environment state.

32. The method of claim 28 further comprising:

compensating a drift of a temperature-compensated crystal oscillator (TCXO) frequency using interpolation based on the determined environmental state while the plurality of modules are powered down.