Centralized database system for a wireless location system

• US 6,317,604 B1
• Filed: 03/31/2000
• Issued: 11/13/2001
• Est. Priority Date: 01/08/1999
• Status: Expired due to Term

• Current Assignee: Skyhook Holding, Inc. (Liberty Broadband Corp.)
• Original Assignee: TruePosition Incorporated
• Inventors: Solley, John, Ginter, Thomas, Brigidi, Anthony Richard, Kovach, Michael John Jr., McCook, Edwin E., Anderson, Robert J., Sachdev, Vineet, Sheehan, Joseph W., Stilp, Louis A.
• Primary Examiner(s): Vo, Nguyen T.
• Assistant Examiner(s): Moore, James K
• Application Number:
  US09/539,352
• Time in Patent Office: 592 Days
• Field of Search: 455/456, 455/457, 342/457, 379/45
• US Class Current: 455/456.5
• CPC Class Codes: G01S 1/026 of associated receivers
• CPC Class Codes: G01S 2205/006 for emergency situations
• CPC Class Codes: G01S 2205/008 using a mobile telephone network
• CPC Class Codes: G01S 2205/06 Emergency
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence
• CPC Class Codes: G01S 5/0215 Interference
• CPC Class Codes: G01S 5/0218 Multipath in signal reception
• CPC Class Codes: G01S 5/02216 Timing or synchronisation of the receivers
• CPC Class Codes: G01S 5/0244 Accuracy or reliability of position solution or of measurements contributing thereto
• CPC Class Codes: G01S 5/0246 involving frequency difference of arrival or Doppler measurements G01S5/02685 takes precedence
• CPC Class Codes: G01S 5/02521 using a radio-map
• CPC Class Codes: G01S 5/0268 by deriving positions from different combinations of signals or of estimated positions in a single positioning system
• CPC Class Codes: G01S 5/0284 Relative positioning
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 76/50 for emergency connections
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A centralized database system is used in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system. The centralized database system includes a computer, a database, and a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information.

Claims

1. A centralized database system for use in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system, the centralized database system comprising:

a computer;

a database; and

a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information;

wherein the wireless location system is capable of independently detecting and demodulating wireless transmissions, and a single wireless transmission can be detected and demodulated at multiple SCS'"'"'s within the wireless location system; and

wherein, when the wireless location system detects and successfully demodulates the same transmission multiple times at multiple SCS'"'"'s, a plurality of prescribed criteria are used to select one demodulating SCS and antenna to use in the process of determining whether to trigger and initiate location processing, said plurality of criteria including the following criterion;

an SCS/antenna collocated at a cell site to which a particular frequency has been assigned is preferred to another SCS/antenna.

2. A centralized database system as recited in claim 1, wherein said plurality of prescribed criteria further include the following:

SCS/antennas with higher average SNR are preferred over those with lower average SNR.

3. A centralized database system as recited in claim 1, wherein said plurality of prescribed criteria further include the following:

SCS/antennas with fewer bit errors are preferred over those with higher bit errors.

4. A centralized database system as recited in claim 1, 2, or 3, wherein a weighting applied to each of the criteria is adjustable by the operator of the wireless location system.

5. A centralized database system as recited in claim 1, wherein the criterion is adjusted if there is no operating and on-line SCS/antenna collocated at the cell site to which the particular frequency has been assigned.

6. A centralized database system as recited in claim 1, wherein the centralized database system is part of a wireless location system that communicates messages over an interface to a wireless communications system, including a mobile switching center (MSC) or a mobile positioning controller (MPC).

7. A centralized database system as recited in claim 6, wherein the interface employs a standard secure protocol.

8. A centralized database system as recited in claim 7, wherein the protocol is IS-41.

9. A centralized database system as recited in claim 7, wherein the protocol is TCP/IP.

10. A centralized database system as recited in claim 6, wherein the wireless location system supports command/response and informational messages communicated over said interface, wherein the messages aid in the successful detection, demodulation and triggering of wireless transmissions, and in passing location records to the wireless communications system.

11. A centralized database system as recited in claim 6, wherein the interface provides a means for the wireless location system to obtain information about which wireless transmitters have been assigned particular voice channel parameters.

12. A centralized database system as recited in claim 6, wherein the interface provides a mechanism for the wireless location system to obtain information about encryption keys assigned to each of a plurality of transmitters.

13. A centralized database system as recited in claim 6, wherein the interface provides a mechanism for the wireless location system to obtain information about which control channels are active at each of a plurality of cell sites.

14. A centralized database system as recited in claim 6, wherein the messages supported by the wireless location system over the interface to the wireless communications system include a query for information concerning the status of a wireless transmitter, wherein the wireless location system initiates the query using certain identifying information and the wireless communications system responds.

15. A centralized database system as recited in claim 14, wherein the identifying information includes a Mobile Directory Number (MDN).

16. A centralized database system as recited in claim 14, wherein the identifying information includes a Mobile Identity Number (MIN).

17. A centralized database system as recited in claim 14, wherein the identifying information includes a Mobile Subscriber Identity (MSID).

18. A centralized database system as recited in claim 14, wherein the identifying information includes an International Mobile Subscriber Identity (IMSI).

19. A centralized database system as recited in claim 14, wherein the identifying information includes a Temporary Mobile Subscriber Identity (TMSI).

20. A centralized database system as recited in claim 14, wherein the information returned comprises an encryption key.

21. A centralized database system as recited in claim 14, wherein the information returned comprises an indication of a voice channel assignment.

22. A centralized database system as recited in claim 14, wherein the information returned comprises a long code.

23. A centralized database system as recited in claim 14, wherein the information returned is a TMSI.

24. A centralized database system as recited in claim 6, wherein the messages supported by the wireless location system over the interface to the wireless communications system include a query for voice channel assignment, wherein, when the wireless location system is triggered to perform location processing on a voice channel transmission, the wireless location system queries the wireless communications system to obtain the current voice channel assignment information for the particular transmitter for which the wireless location system has been triggered.

25. A centralized database system as recited in claim 24, wherein, for an AMPS transmission, the wireless location system queries for the cell site, sector, and RF channel number currently in use by the wireless transmitter.

26. A centralized database system as recited in claim 24, wherein, for a TDMA transmission, the wireless location system queries for the cell site, sector, RF channel number, and timeslot currently in use by the wireless transmitter.

27. A centralized database system as recited in claim 6, wherein the wireless location system includes a mechanism for commanding the wireless communications system to force a particular wireless transmitter to make a transmission at a particular time or within a prescribed range of times.

28. (Amended) A centralized database system as recited in claim 27, wherein the types of transmissions that the wireless location system can force include audit responses and page responses.

29. A centralized database system as recited in claim 6, wherein the wireless location system can command the wireless communications system to force the wireless transmitter to transmit using a higher power level setting.

30. A centralized database system as recited in claim 6, wherein the wireless location system comprises a mechanism for causing the wireless communications system to delay responding to a wireless transmitter when the wireless transmitter initiates transmissions on a channel, whereby the wireless transmitter may be caused to begin a sequence of steps in which it increases the power level of its transmissions.

31. A centralized database system as recited in claim 6, wherein the wireless location system comprises a mechanism for commanding the wireless communications system to transmit a particular message.

32. A centralized database system as recited in claim 31, wherein the particular message includes an audible confirmation tone.

33. A centralized database system as recited in claim 31, wherein the particular message includes a spoken message.

34. A centralized database system as recited in claim 31, wherein the particular message includes a synthesized message to the wireless transmitter.

35. A centralized database system as recited in claim 31, wherein the particular message includes a text message sent via a short messaging service or a page.

36. A centralized database system as recited in claim 6, wherein the wireless location system includes a mechanism for automatically reporting location records to the wireless communications system for those wireless transmitters tasked to report to the wireless communications system.

37. A centralized database system as recited in claim 6, wherein the wireless location system includes a mechanism for automatically reporting location records to the wireless communications system for those transmissions that the wireless communications system initiated triggers.

38. A centralized database system for use in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system, the centralized database system comprising:

a computer;

a database; and

a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information;

wherein the wireless location system communicates messages over an interface to a wireless communications system, including a mobile switching center (MSC) or a mobile positioning controller (MPC);

wherein the messages supported by the wireless location system over the interface to the wireless communications system include a query for voice channel assignment, wherein, when the wireless location system is triggered to perform location processing on a voice channel transmission, the wireless location system queries the wireless communications system to obtain the current voice channel assignment information for the particular transmitter for which the wireless location system has been triggered; and

wherein, to ensure that the identity of the wireless transmitter and the voice channel assignment information are in synchronization, the wireless location system queries the voice channel assignment information for a particular wireless transmitter, receives the necessary RF data, then again queries the voice channel assignment information for that same wireless transmitter, and then verifies that the status of the wireless transmitter did not change during the time in which the RF data was being collected by the wireless location system.

39. A centralized database system as recited in claim 38, wherein, as part of the command/response sequence, the wireless communications system instructs the wireless location system to temporarily suspend location processing until the wireless communications system has completed a handoff sequence with the wireless transmitter, and the wireless communications system has notified the wireless location system that RF data can be received and of the voice channel upon which the data can be received.

40. A centralized database system as recited in claim 38, wherein, if the wireless location system determines that the particular voice channel which a particular wireless transmitter is currently using is unsuitable for obtaining an acceptable location estimate, then the wireless location system requests that the wireless communications system command the wireless transmitter to handoff.

41. A centralized database system for use in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system, the centralized database system comprising:

a computer;

a database; and

a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information;

wherein the wireless location system communicates messages over an interface to a wireless communications system, including a mobile switching center (MSC) or a mobile positioning controller (MPC);

wherein the messages supported by the wireless location system over the interface to the wireless communications system include a query for voice channel assignment;

wherein, when the wireless location system is triggered to perform location processing on a voice channel transmission, the wireless location system queries the wireless communications system to obtain the current voice channel assignment information for the particular transmitter for which the wireless location system has been triggered; and

wherein the wireless location system, as part of a query, commands the wireless communications system to prevent a handoff from occurring for the particular wireless transmitter during the time period in which the wireless location system is receiving RF data.

42. A centralized database system as recited in claim 41, wherein, subsequent to collecting the RF data, the wireless location system again queries the voice channel assignment information for the same wireless transmitter, commands the wireless communications system to again permit handoffs for the wireless transmitter, and then verifies that the status of the wireless transmitter did not change during the time in which the RF data was being collected by the wireless location system.

43. A centralized database system for use in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system, the centralized database system comprising:

a computer;

a database; and

a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information;

wherein the wireless location system communicates messages over an interface to a wireless communications system, including a mobile switching center (MSC) or a mobile positioning controller (MPC); and

wherein the wireless location system uses a command/response message set to query the wireless communications system about the identity of a wireless transmitter that had been using a particular voice channel at a particular cell site at a particular time, whereby the wireless location system is enabled to first perform location processing on transmissions without knowing the identities, and then later to determine the identity of the wireless transmitters making the transmissions and append this information to the location record.

44. A centralized database system for use in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system, the centralized database system comprising:

a computer;

a database; and

a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information;

wherein the wireless location system communicates messages over an interface to a wireless communications system, including a mobile switching center (MSC) or a mobile positioning controller (MPC); and

wherein the wireless location system includes a mechanism for receiving a trigger from the wireless communications system to perform location processing on a voice channel transmission without knowing the identity of the wireless transmitter.

45. A centralized database system as recited in claim 44, wherein the processes include a Tasking process that controls a tasking list within the wireless location system;

wherein a trigger from the wireless communications system bypasses the tasking list, and the wireless location system responds with a confirmation containing a timestamp indicating when RF data was collected.

46. A centralized database system for use in a wireless location system that determines the geographical locations of mobile wireless transmitters, the wireless location system including signal collection systems, location processors for processing digitized RF data provided by the signal collection systems, and a centralized database system for managing resources in the wireless location system, the centralized database system comprising:

a computer;

a database; and

a plurality of software processes for managing the wireless location system, providing interfaces to external users and applications, and storing location records and configuration information; and

wherein the wireless location system includes a mechanism for performing large scale random anonymous location processing, whereby applications that require the gathering of a large volume of data about a population of wireless transmitters are served.

47. A centralized database system as recited in claim 46, wherein an application requesting random anonymous location processing can select to receive location records from a copy of location records generated for all other applications.

48. A centralized database system as recited in claim 46, wherein an application requesting random anonymous location processing can select to receive location records from location records which have been triggered randomly by the wireless location system without regard to any specific criteria.

49. A centralized database system as recited in claims 47 or 48, wherein the location records are forwarded to the application with identity information removed from the location record messages.

50. A centralized database system as recited in claims 47 or 48, wherein the location records are forwarded to the application with trigger criteria information removed from the location record messages.

51. A centralized database system as recited in claim 46, wherein random location records are generated by a low priority task within the wireless location system that performs location processing on randomly selected transmissions when processing and communications resources are available and would otherwise be unused at a particular time.

52. A centralized database system as recited in claim 46, wherein the requesting application(s) can specify whether the random location processing is performed over the entire coverage area of a wireless location system.

53. A centralized database system as recited in claim 46, wherein the requesting application(s) can specify whether the random location processing is performed over specific geographic areas.

54. A centralized database system as recited in claim 46, wherein the requesting application(s) can specify whether the random location processing is performed by the coverage areas of specific cell sites.

55. A centralized database system as recited in claim 46, wherein the wireless location system includes a mechanism for triggering location processing on a repetitive basis for anonymous groups of wireless transmitters within a prescribed geographic area.