GPS-based positioning system for mobile GPS terminals

• US 7,352,322 B2
• Filed: 12/19/2005
• Issued: 04/01/2008
• Est. Priority Date: 04/05/2001
• Status: Expired due to Term

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: Asahi Matsushita Electric Works Ltd. (Panasonic Holdings Corporation), SIRF Technology Incorporated (Qualcomm, Inc.)
• Inventors: Chang, Chiayee Steve, Tsujimoto, Ikuo, Suzuki, Junichi, Garin, Lionel Jacques, Pande, Ashutosh
• Primary Examiner(s): PHAN, DAO LINDA
• Application Number:
  US11/312,250
• Publication Number:
  US 20060202887A1
• Time in Patent Office: 834 Days
• Field of Search: 342/357.05, 342/357.06, 342/357.09, 342/357.12, 342/357.1, 701/213, 701/215
• US Class Current: 342/357.43
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/09 providing processing capability normally carried out by the receiver
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 5/0009 Transmission of position information to remote stations involving assistance data G01S5/0236

Abstract

The present invention discloses a GPS system that uses call-processor intelligence to determine the mode of operation of a GPS receiver located in a GPS terminal. The modes are selected based on the availability of network facilities, the GPS information that can be acquired, or user input requirements.

Claims

1. A Global Positioning System (GPS)-based positioning system, comprising:

(a) a GPS terminal, including;

(i) a GPS section for receiving and processing a GPS signal;

(ii) a strategy selector, external to and coupled to the GPS section, that determines a positioning strategy based upon a state of the GPS section and has a mode determinator for determining a mode of operation of the GPS section that uses positioning requirements received from the GPS section; and

(iii) a communication system, coupled to the GPS section and the strategy selector, for transmitting and receiving data to and from a location aiding server, and

(b) a location aiding server, which communicates with the communications system of the GPS terminal via a communication network including;

(i) an aiding data generation section for forming location aiding date; and

(ii) a communication control section for transmitting date to and receiving data from the GPS terminal.

2. The system of claim 1, wherein the location aiding server calculates a position of the GPS terminal based upon date received from the GPS terminal.

3. The system of claim 1, wherein the state of the GPS section is determined by at least one parameter selected from a group comprising:

a signal level of received satellite signals, a number of satellites from which signals are being received, a frequency range used for searching for satellites, a time range used for searching for satellites, a current searching status, and a state in a positioning process sequence.

4. The system of claim 1, further comprising a time estimator for computing an estimated positioning time based upon the state of the GPS section, wherein the mode determinator determines the mode of operation of the GPS section based upon computed estimated positioning time.

5. The system of claim 1, wherein the mode determinator determines the mode of operation by using at least one parameter selected from a group comprising:

a communication state of the communications network between the GPS terminal and the location aiding server, a communications cost, and a user request, wherein the user request is at least on request selected from a group comprising;

positioning accuracy, positioning time, positioning costs, and positioning sensitivity.

6. The system of claim 5, wherein the communication state is determined by at least one parameter selected from a group comprising:

an availability of a communication link to the location aiding server, an effective data transmission rate between the GPS terminal and the location aiding server, and a communication delay characteristic between the GPS terminal and the location aiding server.

7. The system of claim 1, wherein the GPS terminal further comprises a terminal destination calculator for selecting a destination of a terminal calculated position of the GPS terminal and for sending the position, and wherein the location aiding server further comprises a server destination calculator for selecting a destination of a server calculated position of the GPS terminal and for sending a server calculated position of the GPS terminal.

8. The system of claim 7, wherein the destination of the calculated position of the GPS terminal is shared between the GPS terminal and the location aiding server.

9. The system of claim 1, wherein the strategy selector comprises an aiding data determinator for determining a method for acquiring position aiding data based upon the state of the GPS section.

10. The system of claim 9, wherein the state of the GPS section is determined by at least on parameter selected from a group comprising a signal level of received satellite signals, number of satellites from which signals are being received, a frequency range used for searching for satellites, a time range used for searching for satellites, a current searching status, and a state in a positioning process sequence.

11. The system of claim 9, further comprising a time estimator for computing an estimated positioning time based upon the state of the GPS section, wherein the aiding data determinator determines the acquiring method based upon the computed estimated positioning time.

12. The system of claim 9, wherein the aiding data determinator determines the acquiring method based on at least one parameter selected from a group comprising:

a communication state of the communications network between the GPS terminal and the location aiding server, a communications cost, and a user request, wherein the user request us at least one request selected from a group comprising;

positioning accuracy, positioning time, positioning costs, and positioning sensitivity.

13. The system of claim 1, wherein the communication state of the network is determined by at least one parameter selected from a group comprising:

an availability of a communication link to the location aiding server, an effective data transmission rate of the network and communication delay characteristic of the network.

14. The system of claim 9, wherein the GPS terminal further comprises a terminal destination calculator for selecting a destination for the GPS terminal calculated position of the GPS terminal, and wherein the location aiding server further comprises a server destination calculator for selecting a destination for the GPS terminal and for sending a server calculated position of the GPS terminal.

15. The system of claim 14, wherein at least one of the server calculated position and the terminal calculated position of the GPS terminal is shared between the GPS terminal and the location aiding server.

16. The system of claim 9, wherein the aiding date being sent from the aiding date determinator to the GPS section is dynamically altered based on a change in the state of the GPS section.

17. The system of claim 1, wherein the GPS Section and the strategy selector pass information between the GPS section and the strategy selector.

18. The system of claim 17, wherein the information is selected from a group comprising real time data of the GPS section and a quality of service message.

19. The system of claim 18, wherein the quality of service message is at least one message selected from a group comprising:

a request or automated positioning accuracy, a request or estimated positioning time, a request positioning sensitivity, or information for the necessity of aiding date, and a preferred mode of operation.