Method and System for Determining Position of Terminal by Using Gps Terminal and Location Detector in Gps Satellite-Invisible Area

• US 20080238764A1
• Filed: 06/03/2004
• Published: 10/02/2008
• Est. Priority Date: 01/20/2004
• Status: Abandoned Application

• Current Assignee: SK Telecom Co., Ltd.
• Original Assignee: SK Telecom Co., Ltd.
• Inventors: Han, Gyuyoung, Lee, Jaemoon, Jeon, Sangchoon, Ihm, Jongtae, Shin, Sungho, Cho, Sungmin
• Application Number:
  US10/586,681
• Publication Number:
  US 20080238764A1
• Time in Patent Office: Days
• US Class Current: 342/357.1
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: G01S 5/145 Using a supplementary range measurement, e.g. based on pseudo-range measurements

Abstract

The method for finding location of a GPS terminal in a GPS satellite-invisible area by using a mapping server including the mobile terminal, a location detector, a PDE, and a database, comprising: (a) obtaining a reference pilot signal of a base station or a repeater and a LD pilot signal from the location detector; (b) transmitting information on the reference pilot signal or the LD pilot signal to the PDE, if a strength of the reference pilot signal or the LD pilot signal is determined to be larger than a prescribed value; (c) calculating a pseudo noise code phase value per chip from the PSMM; (d) transmitting the pseudo noise code phase value to the LD mapping server, if the pseudo noise code phase value calculated at step (c) is determined to be a pseudo noise code phase value served for a location detection; and (c) obtaining a location information of the GPS terminal by using the pseudo noise code phase value transmitted at step (d).

Claims

1. A global positioning system (GPS) terminal positioning method in a GPS satellite-invisible area by using a GPS terminal, a plurality of location detectors (LDs) for applying and sending offsets, respectively, a position determination entity (PDE) for controlling a position determination of the GPS terminal and an LD mapping server including a location information associated database, comprising the steps of:

(a) allowing the GPS terminal in which a positioning request is received to obtain a reference pilot signal of a base transceiver station or a repeater and LD pilot signals generated from the location detectors;

(b) if the reference pilot signal or the LD pilot signals are received with a strength not smaller than a predetermined value, transmitting information on the reference pilot signal or the LD pilot signals to the PDE;

(c) calculating a chip-based pseudo noise code phase from the information on the reference pilot signal or the LD pilot signals transmitted to the PDE;

(d) if the pseudo noise code phase calculated at step (c) is a phase of one of position pseudo noise codes allocated for the position determination, transmitting the pseudo noise code phase to the LD mapping server; and

(e) obtaining location information on the GPS terminal by using the pseudo noise code phase transmitted to the LD mapping server.

2. The method of claim 1, wherein the position pseudo noise codes are predetermined in a CDMA (code division multiple access) system.

3. The method of claim 1, wherein at least two position pseudo noise codes are predetermined.

4. The method of claim 1, wherein the LD pilot signals are generated by applying offsets to the position pseudo noise codes, respectively.

5. The method of claim 1, wherein each of the offsets is not larger than 64 chips.

6. The method of claim 1, wherein, if two position pseudo noise codes are predetermined, the difference between respective offsets to be added in the LD pilot signals is not larger than 128 chips.

7. The method of claim 1, wherein the difference between respective offsets to be added in the LD pilot signals generated from each LD corresponds to a unique identifier for differentiating said each LD from the other LDs.

8. The method of claim 1, wherein the LD pilot signals are transmitted with a strength which is lower than that of the reference pilot signal.

9. The method of claim 1, wherein, at step (b), the GPS terminal transmits the information on the reference pilot signal or the LD pilot signals to the PDE by using a “

Provide_Pilot_Phase_Measurement”

message defined by an Interim Standard (IS)-801-1 standard.

10. The method of claim 1, wherein, at step (b), the predetermined value is T DROP.

11. The method of claim 1, wherein, at step (b), the information on the reference pilot signal transmitted from the GPS terminal is at least one of a pseudo noise code phase of the reference pilot signal, the strength of the reference pilot signal and a measurement error of the pseudo noise code phase.

12. The method of claim 1, wherein the information on the LD pilot signals transmitted from the GPS terminal is at least one of a pseudo noise code phase of each LD pilot signals, the strength of each LD pilot signal and a measurement error of the pseudo noise code phase.

13. The method of claim 11, wherein the phase is measured and transmitted on a 1/16 chip basis.

14. The method of claim 1, wherein, in the location information associated database, the difference between respective offsets to be added in the LD pilot signals generated from each LD corresponds to the location information including an address, a name, a floor or a representative shop of its corresponding building.

15. The method of claim 1, wherein the GPS terminal includes PDA (Personal Digital Assistant), cellular phone, PCS (Personal Communication Service) phone, hand-held PC (Personal Computer), GSM (Global System for Mobile) phone, W-CDMA (Wideband CDMA) phone, EV-DO (Evolution Data Only) phone, EV-DV (Evolution Data and Voice) phone and MBS (Mobile Broadband System) phone.

16. The method of claim 1, wherein the PDE performs the position determination with A-GPS algorithm by using GPS satellite information received from the GPS terminal and, if it is impossible to perform the position determination, the steps (a) to (e) are processed.

31. The method of claim 12, wherein the phase is measured and transmitted on a 1/16 chip basis.

17. A global positioning system (GPS) terminal positioning system in a GPS satellite-invisible area, comprising:

a plurality of location detectors (LDs) for applying preset offsets to position pseudo noise codes predetermined in a code division multiple access (CDMA) system, respectively, to generate and send LD pilot signals;

a GPS terminal, if a positioning request is received, for obtaining a reference pilot signal of a base transceiver station or a repeater and the LD pilot signals and, if the reference pilot signal or the LD pilot signals are received with a strength not smaller than a predetermined value, for transmitting information on the reference pilot signal or the LD pilot signals;

a position determination entity (PDE) for calculating a chip-based pseudo noise code phase from the information on the reference pilot signal or the LD pilot signals received from the GPS terminal and, if the calculated pseudo noise code phase is a phase of one of position pseudo noise codes, transmitting the calculated pseudo noise code phase; and

a LD mapping server for generating location information of the GPS terminal by using the pseudo noise code phase received from the PDE.

18. The system of claim 17, wherein at least two position pseudo noise codes are predetermined.

19. The system of claim 17, wherein each of the offsets is not larger than 64 chips.

20. The system of claim 17, wherein, if two position pseudo noise codes are predetermined, the difference between respective offsets to be added in the LD pilot signals is not larger than 128 chips.

21. The system of claim 17, wherein the difference between respective offsets to be added in the LD pilot signals generated from each LD corresponds to a unique identifier for differentiating said each LD from the other LDs.

22. The system of claim 17, wherein the LD pilot signals are transmitted with a strength which is lower than that of the reference pilot signal.

23. The system of claim 17, wherein the GPS terminal transmits the information on the reference pilot signal or the LD pilot signals to the PDE by using a “

Provide_Pilot_Phase_Measurement”

message defined by an Interim Standard (IS)-801-1 standard.

24. The system of claim 17, wherein the predetermined value is T_DROP.

25. The system of claim 17, wherein the information on the reference pilot signal transmitted from the GPS terminal is at least one of a pseudo noise code phase of the reference pilot signal, the strength of the reference pilot signal and a measurement error of the pseudo noise code phase.

26. The system of claim 17, wherein the information on the LD pilot signals transmitted from the GPS terminal is at least one of a pseudo noise code phase of each LD pilot signal, the strength of each LD pilot signal and a measurement error of the pseudo noise code phase.

27. The system of claim 25, wherein the phase is measured and transmitted on a 1/16 chip basis.

28. The system of claim 17, wherein the LD mapping server includes a location information associated database in which the difference between respective offsets to be added in the LD pilot signals generated from each LD corresponds to the location information including an address, a name, a floor or a representative shop of its corresponding building.

29. The system of claim 17, wherein the GPS terminal includes PDA (Personal Digital Assistant), cellular phone, PCS (Personal Communication Service) phone, hand-held PC (Personal Computer), GSM (Global System for Mobile) phone, W-CDMA (Wideband CDMA) phone, EV-DO (Evolution Data Only) phone, EV-DV (Evolution Data and Voice) phone and MBS (Mobile Broadband System) phone.

30. The system of claim 17, further comprising GPS satellites for transmitting, to the GPS terminal, navigation data required to calculate the position of the GPS terminal by using A-GPS algorithm or C-GPS algorithm.

32. The system of claim 26, wherein the phase is measured and transmitted on a 1/16 chip basis.