MOBILE TERMINAL AND POSITIONING SATELLITES SELECTING METHOD THEREOF

• US 20130162468A1
• Filed: 12/21/2012
• Published: 06/27/2013
• Est. Priority Date: 12/23/2011
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: KIM, Dongseon, SHIN, Hangle
• Granted Patent: US 9,989,647 B2
• Time in Patent Office: Days
• US Class Current: 342/357.25
• CPC Class Codes: G01S 19/28 Satellite selection
• CPC Class Codes: G01S 19/32 Multimode operation in a single same satellite system, e.g. GPS L1/L2
• CPC Class Codes: G01S 19/33 Multimode operation in different systems which transmit time stamped messages, e.g. GPS/GLONASS
• CPC Class Codes: G01S 19/423 by combining or switching between position solutions derived from different satellite radio beacon positioning systems
• CPC Class Codes: G01S 19/425 by combining or switching between signals derived from different satellite radio beacon positioning systems
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 5/01 Determining conditions which influence positioning, e.g. radio environment, state of motion or energy consumption
• CPC Class Codes: G01S 5/019 Energy consumption

Abstract

A mobile terminal capable of selecting optimum satellites among a plurality of positioning satellites and a method of selecting positioning satellites are disclosed with reference to embodiments of the present invention. If DOP (dilution of precision) increases as the number of positioning satellites increases, satellites to be used for positioning are automatically selected from GNSS satellites based on satellite information and a user'"'"'s menu setting. This can enhance the accuracy of positioning and can reduce battery consumption. In particular, satellites for positioning are spaced from each other by a prescribed distance to reduce DOP, thereby enhancing the accuracy of positioning. Further, multipath signals are reduced in order to enhance the accuracy of positioning.

Claims

1. A method of selecting positioning satellites by a mobile terminal, the method comprising:

storing setting information of a satellite mode regarding a plurality of satellites;

sequentially selecting satellites of the plurality of satellites that satisfy a condition relating to dilution of precision (DOP) based on satellite information and the stored setting information; and

performing positioning of the mobile terminal by using the selected satellites.

2. The method of claim 1, wherein the setting information is information received from a user via a satellite setting menu, the setting information comprising a satellite mode, a satellite type, a total number of satellites, a satellite selection procedure, satellite selecting priorities per area, a number of satellites to be selected, and charge information.

3. The method of claim 1, wherein each of the plurality of satellites belongs to a free satellite system or a pay satellite system, the plurality of satellites including Global Positioning System (GPS), Global Navigation Satellite System (GLONASS), COMPASS, Quasi-Zenith Satellite System (QZSS) and Galileo satellites.

4. The method of claim 1, wherein:

the satellite information includes a signal strength, an azimuth and an elevation; and

the satellite information is directly measured from a satellite signal, or is received from an external server.

5. The method of claim 1,

wherein sequentially selecting the satellites of the plurality of satellites includes:

checking whether a satellite mode has been set;

performing positioning using Global Positioning System (GPS) satellites if either no satellite mode has been set or a GPS mode has been set; and

selecting Global Navigation Satellite System (GNSS) satellites by converting to a GNSS mode if a signal strength or a positioning accuracy is less than a prescribed value while performing the positioning using the GPS satellites; and

wherein performing the positioning comprises using the GPS satellites and the selected GNSS satellites.

6. The method of claim 5, wherein selecting the GNSS satellites comprises displaying a pop-up message asking a user whether to convert to the GNSS mode.

7. The method of claim 5, wherein:

the GPS satellites belong to a free satellite system;

the GNSS satellites belong to a free satellite system or a pay satellite system; and

the GNSS satellites are selected according to signal strengths, priorities per area, area information, and charge information.

8. The method of claim 1, wherein sequentially selecting the satellites of the plurality of satellites includes:

selecting a satellite of the plurality of satellites having a highest signal strength as a reference satellite;

comparing an azimuth and an elevation of the reference satellite with azimuths and elevations of other satellites of the plurality of satellites;

selecting satellites of the other satellites having prescribed differences in azimuth and elevation with respect to the azimuth and the elevation of the reference satellite as candidate satellites; and

sequentially selecting the candidate satellites according to signal strengths or priorities per area.

9. The method of claim 8, wherein satellites of the other satellites having higher elevations are selected as the candidate satellites if the azimuths of the other satellites are out of range based on the azimuth of the reference satellite.

10. The method of claim 1, wherein sequentially selecting the satellites of the plurality of satellites includes:

sorting the plurality of satellites according to at least one candidate sector based on an azimuth and an elevation of each of the plurality of satellites; and

sequentially selecting from each of the at least one candidate sector satellites having higher signal strengths.

11. The method of claim 10, wherein sequentially selecting satellites having higher signal strengths comprises first selecting from each of at least one candidate sector a satellite belonging to a same satellite system as a reference satellite or a satellite belonging to a free satellite system from among at least two satellites having a signal strength difference within a prescribed range.

12. The method of claim 11, wherein a sector of the at least one candidate sector including only satellites belonging to a pay satellite system is excluded as a candidate sector if a user has selected a free satellite system.

13. The method of claim 1, wherein a number of the selected satellites corresponds to a minimum number or a maximum number based on the stored setting information.

14. The method of claim 1, further comprising adjusting a number of satellites used for performing positioning based on a signal strength, positioning accuracy, and a remaining charge of a battery of the mobile terminal.

15. The method of claim 14, wherein:

a number of satellites belonging to a free satellite system is first increased if adjusting the number of satellites comprises increasing the number of satellites used for performing positioning; and

a number of satellites belonging to a pay satellite system is first decreased if adjusting the number of satellites comprises decreasing the number of satellites used for performing positioning.

16. The method of claim 14, wherein performing the positioning comprises using a maximum number of satellites according to priorities if the signal strength or the positioning accuracy is less than a prescribed value and the number of satellites used for positioning has been set to a minimum number.

17. The method of claim 14, wherein performing the positioning comprises using a minimum number of satellites if a remaining charge of a battery of the mobile terminal is less than a prescribed level and the number of satellites used for positioning has been set to a maximum number.

18. A mobile terminal comprising:

a memory configured to store setting information of a satellite mode regarding a plurality of satellites;

a display unit configured to display information regarding the plurality of satellites; and

a controller configured to sequentially select satellites of the plurality of satellites that satisfy a condition relating to dilution of precision (DOP) based on satellite information and the stored setting information and to perform positioning of the mobile terminal by using the selected satellites.

19. The mobile terminal of claim 18, wherein the setting information is information received from a user via a satellite setting menu, the setting information comprising a satellite mode, a satellite type, a satellite selection procedure, satellite selecting priorities per area, a number of satellites to be selected, and charge information.

20. The mobile terminal of claim 18, wherein each of the plurality of satellites belongs to a free satellite system or a pay satellite system, and include Global Positioning System (GPS), Global Navigation Satellite System (GLONASS), COMPASS, Quasi-Zenith Satellite System (QZSS) and Galileo satellites.

21. The mobile terminal of claim 18, wherein:

the satellite information includes a signal strength, an azimuth and an elevation; and

the satellite information is directly measured from a satellite signal or is received from an external server.

22. The mobile terminal of claim 18, wherein the controller is further configured to:

perform positioning using Global Positioning System (GPS) satellites if either no satellite mode has been set or a GPS mode has been set;

select Global Navigation Satellite System (GNSS) satellites by converting to a GNSS mode if a signal strength or a positioning accuracy is less than a prescribed value while performing the positioning using the GPS satellites; and

perform the positioning using the GPS satellites and the selected GNSS satellites.

23. The mobile terminal of claim 22, wherein the controller is further configured to control the display unit to display a pop-up message asking a user whether to convert to the GNSS mode when converting to the GNSS mode.

24. The mobile terminal of claim 22, wherein the controller is further configured to select the GNSS satellites according to signal strengths, priorities per area, area information, and charge information.

25. The mobile terminal of claim 18, wherein the controller is further configured to:

compare an azimuth and an elevation of a reference satellite having a highest signal strength with azimuth and elevations of other satellites of the plurality of satellites;

select satellites of the other satellites having a prescribed difference in azimuth and elevation with respect to the azimuth and the elevation of the reference satellite as candidate satellites; and

sequentially select the candidate satellites according to signal strengths or priorities per area.

26. The mobile terminal of claim 18, wherein the controller is further configured to:

sort the plurality of satellites according to at least one candidate sector based on an azimuth and an elevation included in the satellite information; and

sequentially select from each of the at least one candidate sector satellites having high signal strengths.

27. The mobile terminal of claim 26, wherein the controller is further configured to first select from each of the at least one candidate sector a satellite belonging to a same satellite system as a reference satellite or a satellite belonging to a free satellite system from among at least two satellites having a signal strength difference within a prescribed range.

28. The mobile terminal of claim 18, wherein the controller is further configured to adjust a number of satellites used for positioning based on a signal strength, positioning accuracy, and a remaining charge of a battery of the mobile terminal.

29. The mobile terminal of claim 28, wherein the controller is further configured to:

first increase a number of satellites belonging to a free satellite system if the number of satellites used for positioning is to be increased; and

first decrease a number of satellites belonging to a pay satellite system if the number of satellites used for positioning is to be decreased.

30. The mobile terminal of claim 28, wherein the controller is further configured to perform the positioning using a maximum number of satellites according to priorities if the signal strength or the positioning accuracy is less than a prescribed value and the number of satellites used for positioning has been set to be a minimum number.

31. The mobile terminal of claim 28, wherein the controller is further configured to perform the positioning using a minimum number of satellites if a remaining charge of a battery is less than a prescribed level and the number of satellites used for positioning has been set to a maximum number.