Method and apparatus for geo-fence detection

• US 10,067,237 B1
• Filed: 02/29/2016
• Issued: 09/04/2018
• Est. Priority Date: 03/12/2014
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Liu, BoChih, Jia, Zhike, Chen, Jian, Yu, Jing, Qiu, Mobo
• Primary Examiner(s): Liu, Harry K
• Application Number:
  US15/056,569
• Time in Patent Office: 918 Days
• Field of Search: 34235725
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 19/34 Power consumption
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G01S 19/52 Determining velocity

Abstract

Aspects of the disclosure provide an apparatus that includes a sensor module and a navigation signal receiver. The sensor module is configured to generate signals indicative of motions of the apparatus. The navigation signal receiver includes receiver circuitry and processor circuitry. The receiver circuitry is configured to receive satellite navigation signals from a plurality of satellites. The processor circuitry is configured to determine a velocity of the apparatus based on the satellite navigation signals, receive an estimated speed from the sensor module, calibrate a moving speed based on the velocity and the estimated speed, and determine a power saving time based on the calibrated moving speed. The power saving time is an amount of time that the navigation signal receiver is to stay in a power saving mode.

Claims

1. A circuit for geo-fence detection, the circuit comprising:

receiver circuitry configured to receive satellite navigation signals from a plurality of satellites; and

processor circuitry configured to;

determine a velocity of the circuit based on the satellite navigation signals received from the plurality of satellites,

receive an estimated speed of the circuit from a sensor module,

calibrate a moving speed of the circuit based on the velocity and the estimated speed, wherein the calibration relies more on the satellites than the sensor module when the circuit is in a fast motion and the calibration relies more on the sensor module than the satellites when the circuit is in a slow motion,

determine a power saving time based on the calibrated moving speed, wherein the power saving time is an amount of time that the circuit is to stay in a power saving mode,

determine a position of the circuit based on the received satellite navigation signals, and detect a geo-fence event when the circuit crosses a border of a geo-fence area based on the position, and

calculate a distance between the position and a center position of the geo-fence area, and determine whether the circuit is in or out of the geo-fence area.

2. The circuit of claim 1, wherein the processor circuitry is configured to turn off the receiver circuitry in the power saving mode.

3. The circuit of claim 1, wherein the processor circuitry is configured to detect the slow motion of the circuit based on a signal from the sensor module, and calibrate the moving speed based on the estimated speed from the sensor module.

4. The circuit of claim 1, wherein the processor circuitry is configured to predict, based on the calibrated moving speed, a time duration without the geo-fence event, and determine the power saving time based on the time duration.

5. The circuit of claim 1, wherein the processor circuitry is configured to signal an application processor when the circuit crosses the border of the geo-fence area.

6. A method for geo-fence detection, the method comprising:

detecting a motion mode of a device;

receiving an estimated speed of the device from a sensor module in the device;

calibrating a moving speed of the device in the motion mode based on a velocity and the estimated speed from the sensor module, the velocity being determined based on satellite navigation signals from satellites, wherein the calibration relies more on the satellites than the sensor module when the motion mode is a fast motion mode and the calibration relies more on the sensor module than the satellites when the motion mode is in a slow motion mode;

determining a power saving time based on the calibrated moving speed, wherein the power-saving time is an amount of time that the device is to stay in a power saving mode;

determining a position of the device based on the satellite navigation signals, and detect a geo-fence event when the device crosses a border of a geo-fence area based on the position; and

calculating a distance between the position and a center position of the geo-fence area, and determine whether the device is in or out of the geo-fence area.

7. The method of claim 6, further comprising:

turning off a receiver circuitry in the power saving mode, wherein the receiver circuitry receives the satellite navigation signals in an active mode.

8. The method of claim 6, wherein

detecting the slow motion mode of the device based on a signal from the sensor module;

and

calibrating the moving speed based on the estimated speed from the sensor module when the device is in the slow motion mode.

9. The method of claim 6, wherein determining the power-saving time based on the calibrated moving speed further comprises:

predicting, based on the calibrated moving speed, a time duration without the geo-fence event; and

determining the power saving time based on the time duration.

10. The method of claim 6, wherein detecting the geo-fence event when the device crosses the border of the geo-fence area based on the position further comprises:

comparing the distance with a radius of the geo-fence to determine whether the device is in/out of the geo-fence area.

11. An apparatus, comprising:

a sensor module configured to generate signals indicative of motions of the apparatus; and

a navigation signal receiver that includes

receiver circuitry configured to receive satellite navigation signals from a plurality of satellites; and

processor circuitry configured to;

determine a velocity of the apparatus based on the satellite navigation signals received from the plurality of satellites,

receive an estimated speed of the apparatus from the sensor module,

calibrate a moving speed of the apparatus based on the velocity and the estimated speed, wherein the calibration relies more on the satellites than the sensor module when the circuit is in a fast motion and the calibration relies more on the sensor module than the satellites when the circuit is in a slow motion,

determine a power saving time based on the calibrated moving speed, wherein the power saving time is an amount of time that the navigation signal receiver is to stay in a power saving mode,

determine a position of the apparatus based on the received satellite navigation signals, and detect a geo-fence event when the apparatus crosses a border of a geo-fence area based on the position, and

calculate a distance between the position and a center position of the geo-fence area, and determine whether the apparatus is in or out of the geo-fence area.

12. The apparatus of claim 11, wherein the processor circuitry is configured to turn off the receiver circuitry in the power saving mode.

13. The apparatus of claim 11, wherein the processor circuitry is configured to detect the slow motion of the apparatus based on a signal from the sensor module, and calibrate the moving speed based on the estimated speed from the sensor module.

14. The apparatus of claim 11, wherein the processor circuitry is configured to predict, based on the calibrated moving speed, a time duration without the geo-fence event, and determine the power saving time based on the time duration.

15. The apparatus of claim 11, wherein the processor circuitry is configured to signal an application processor when the apparatus crosses the border of the geo-fence area.