Method and apparatus for generating and outputting a location data stream

• US 8,060,108 B1
• Filed: 04/19/2007
• Issued: 11/15/2011
• Est. Priority Date: 04/19/2007
• Status: Active Grant

• Current Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Original Assignee: Sprint Spectrum LP (Deutsche Telekom AG)
• Inventors: Rayburn, Terry G., McMullen, Michael P.
• Primary Examiner(s): AJIBADE AKONAI, OLUMIDE
• Application Number:
  US11/737,485
• Time in Patent Office: 1,671 Days
• Field of Search: 455/427, 455/404.2, 455/41.2, 455/41.3, 455/443, 4554561-4566, 455/556.1, 455/557, 455/432.1, 455/3.06, 342/356, 342/357.01, 342/357.03, 342/357.06, 342/357.07, 342/357.08, 342/357.09, 342/357.1, 342/357.12, 342/357.13, 342/357.17
• US Class Current: 455/456.1
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01S 19/26 involving a sensor measurement for aiding acquisition or tracking
• CPC Class Codes: G01S 19/42 Determining position

Abstract

A method and apparatus for providing a sequence of location data points to a mapping device. A cellular mobile station uses GPS satellite signals to compute its varying location over time and outputs the location as data points in a sequence to the mapping device. If the mobile station loses satellite communication, it transitions the output sequence to a static state in which the location data points are a substantial repetition of the last location that the mobile station determined from satellite signals. Further, when the mobile station detects that it has entered into a new cellular coverage area, it obtains satellite assistance data from its cellular carrier network and uses the data to renew satellite communication. The mobile station may then transition the sequence back to a dynamic state, with location data points determined over time based on received satellite signals.

Claims

1. A method operable by a mobile station, the method comprising:

generating a sequence of location data points indicating location of the mobile station over time, and transmitting the sequence to a mapping device, wherein the sequence has a dynamic state in which the data points of the sequence vary over time as the mobile station receives varying information from satellites and uses the information to generate the location data points, and the sequence has a static state in which the data points of the sequence are substantially unchanging over time;

detecting a loss of satellite communication, and responsively transitioning the sequence from the dynamic state to the static state, wherein transitioning the sequence from the dynamic state to the static state comprises transitioning to have the location data points of the sequence be a substantially constant repetition of each other, whereby the sequence in the static state received by the mapping device thereby indicates substantially no change in position of the mobile station over time; and

while transmitting the sequence in the static state, detecting transition of the mobile station in cellular network service, and responsively (i) obtaining satellite-assistance data from a cellular radio access network, (ii) using the obtained satellite-assistance data to engage in satellite communication, and (iii) transitioning the sequence from the static state to the dynamic state.

2. The method of claim 1, wherein the mapping device is operable to generate and present an active location-map to a user, and wherein transmitting the sequence to the mapping device comprises transmitting the sequence to the mapping device for use by the mapping device to generate the active location-map.

3. The method of claim 1, wherein the mapping device is operable to log location over time, and wherein transmitting the sequence to the mapping device comprises transmitting the sequence to the mapping device for use by the mapping device to log location.

4. The method of claim 1, further comprising beginning transmission of the sequence in the static state before transmitting the sequence in the dynamic state.

5. The method of claim 4, wherein beginning transmission of the sequence in the static state comprises beginning transmission of the sequence when the mobile station is indoors and lacks sufficient satellite communication to generate the sequence in the dynamic state.

6. The method of claim 1, further comprising detecting restoration of satellite communication, and responsively transitioning the sequence from the static state to the dynamic state.

7. The method of claim 1, wherein detecting transition of the mobile station in cellular network service comprises detecting transition of the mobile station from being served by a first cellular wireless coverage area to being served by a second cellular wireless coverage area, wherein each cellular wireless coverage area is an area selected from the group consisting of a cell and a cell sector.

8. The method of claim 7, wherein detecting transition of the mobile station from being served by the first cellular wireless coverage area to being served by the second cellular wireless coverage area comprises concluding that the mobile station is served by the second wireless coverage area only after a predefined threshold time period of the mobile station being served by the second wireless coverage area.

9. The method of claim 1, wherein detecting transition of the mobile station in cellular network service comprises detecting a threshold change in pilot signal strength from the cellular radio access network.

10. The method of claim 1, wherein obtaining satellite-assistance data from the cellular radio access network comprises requesting the satellite-assistance data and receiving the satellite-assistance data in response.

11. The method of claim 1, wherein the satellite-assistance data comprises data enabling the mobile station to tune to communications with the satellites, and wherein using the obtained satellite-assistance data to engage in satellite communication comprises tuning to communications with the satellites and receiving communications from the satellites.

12. The method of claim 1, wherein the cellular mobile station comprises a cellular telephone.

13. The method of claim 1, wherein the mapping device comprises a personal computer.

14. The method of claim 13, wherein the cellular mobile station comprises a PC card connectable to the personal computer.

15. The method of claim 1, where the sequence of location data points comprises a National Maritime Equipment Association (NMEA) GGA sequence.

16. The method of claim 1, wherein transitioning to have the location data points of the sequence be a substantially constant repetition of each other comprises transitioning to have the location data points of the sequence be a substantially constant repetition of a location data point generated by the mobile station when the sequence was in the dynamic state.

17. The method of claim 16, wherein the location data point of which the location data points of the sequence are a substantially constant repetition is a location data point determined by requesting location of the mobile station from a cellular network based location-determination system.

18. The method of claim 17, wherein the location data point determined by requesting location from the cellular network based location-determination system is determined using advanced forward link trilateration.

19. The method of claim 16, wherein the location data point generated by the mobile station when the sequence was in the dynamic state is a last location data point generated by the mobile station before transitioning the sequence from the dynamic state to the static state.

20. A cellular mobile station comprising:

a cellular wireless transceiver for communicating with a cellular radio access network;

a processor;

data storage;

first logic stored in the data storage and executable by the processor to generate a sequence of location data points indicating location of the mobile station over time, and to transmit the sequence to a mapping device for use by the mapping device to generate and present an active location-map to a user, wherein the sequence has a dynamic state in which the data points of the sequence vary over time as the mobile station receives varying information from satellites and uses the information to generate the location data points, and the sequence has a static state in which the data points of the sequence are substantially unchanging over time;

second logic stored in the data storage and executable by the processor to detect loss of satellite communication and to responsively transition the sequence from the dynamic state to the static state, wherein transitioning the sequence from the dynamic state to the static state comprises transitioning to have the location data points of the sequence be a substantially constant repetition of each other, whereby the sequence in the static state received by the mapping device thereby indicates substantially no change in position of the mobile station over time;

third logic stored in the data storage and executable by the processor, while the mobile station is transmitting the sequence in the static state, to detect transition of the mobile station into a new cellular wireless coverage area and to responsively (i) obtain satellite-assistance data from a cellular radio access network, (ii) use the obtained satellite-assistance data to engage in satellite communication, and (iii) transition the sequence from the static state to the dynamic state.

21. The cellular mobile station of claim 20, wherein the sequence of location data points comprises a National Maritime Equipment Association (NMEA) GGA sequence.

22. The cellular mobile station of claim 20, wherein the mapping device comprises a personal computer.

23. The cellular mobile station of claim 20, wherein transitioning to have the location data points of the sequence be a substantially constant repetition of each other comprises transitioning to have the location data points of the sequence be a substantially constant repetition of a location data point generated by the mobile station when the sequence was in the dynamic state.

24. The cellular mobile station of claim 23, wherein the location data point of which the location data points of the sequence are a substantially constant repetition is a location data point determined by requesting location of the mobile station from a cellular network based location-determination system.

25. The cellular mobile station of claim 24, wherein the location data point determined by requesting location from the cellular network based location-determination system is determined using advanced forward link trilateration.

26. The cellular mobile station of claim 23, wherein the location data point generated by the mobile station when the sequence was in the dynamic state is a last location data point generated by the mobile station before transitioning the sequence from the dynamic state to the static state.