Method and apparatus for determining location of a base station using a plurality of mobile stations in a wireless mobile network

Abstract

A method and apparatus for determining a position of a base station in a wireless communication network that includes a mobile station in communication with base stations. A BTS calibration server is networked with the base stations. A BTS calibration program is programmed into a group of mobile stations that have position location capabilities. Using the BTS calibration program, calibration information may be requested by the BTS calibration server, or a session may be initiated by the mobile station. The BTS calibration program also provides privacy features that allow user of the mobile station to prevent it from being used for base station location. If authorized, the BTS calibration program determines the position of the mobile station, and provides calibration information, such as position and base station phase measurements, to the server. The calibration information may be used to calibrate the base station almanac.

What is claimed is: 
     
       1. In a wireless communication network that includes a plurality of mobile stations in communication with one or more base stations, a method of determining a position of a base station, comprising:
 a. programming a group of mobile stations with a BTS calibration program, thereby providing a plurality of calibration-enabled mobile stations, wherein each mobile station has a user, and wherein said step of programming a group of mobile stations with the calibration program comprises obtaining consent of the users of said group of mobile phones and then downloading the BTS calibration program into said group of mobile phones; 
 b. providing a BTS calibration server networked with said base station; 
 c. requesting calibration information from at least one of said calibration-enabled mobile stations in communication with a base station; 
 d. determining a position of said calibration-enabled mobile station(s) in communication with said base station; 
 e. receiving a signal from said base station to said mobile station(s) in communication with said base station; 
 f. transmitting calibration information indicative of said position and said signal from said mobile station(s) to the BTS calibration server; and 
 g. in said BTS calibration server, comparing the calibration information with base station almanac information associated with said base station, and calibrating the position of said base station responsive thereto. 
 
     
     
       2. The method of  claim 1  and further comprising a step of determining if the mobile station is authorized to communicate calibration information, if there is no authorization then exiting operation before transmitting calibration information, otherwise completing operation. 
     
     
       3. The method of  claim 2 , wherein each mobile station has a user, and wherein said users of said calibration-enabled mobile phones utilize the BTS calibration program to create privacy settings to indicate authorization to provide calibration information, and said step of determining if the mobile station is authorized to communicate calibration information further comprises checking said privacy settings to verify that the mobile station is authorized to provide calibration information. 
     
     
       4. The method of  claim 1  wherein said step of obtaining consent of the users further comprises creating privacy settings to indicate authorization to provide calibration information. 
     
     
       5. The method of  claim 1  wherein said step of requesting calibration information is initiated by said BTS calibration program when in communication with said base station. 
     
     
       6. The method of  claim 1  wherein said step of requesting calibration information comprises communicating from said BTS calibration server to at least one of the software-enabled mobile stations. 
     
     
       7. The method of  claim 1  wherein said BTSCS selects a target base station, said step of requesting calibration information comprises communicating from said BTS calibration server to at least one of the calibration-enabled mobile stations in communication with the target base station. 
     
     
       8. The method as claimed in  claim 1 , wherein the mobile stations have global satellite receivers, and the positions of the mobile stations are determined from signals received by the mobile stations from global satellites. 
     
     
       9. The method as claimed in  claim 1 , wherein the positions of the mobile stations are determined by Advanced Forward Link Trilateration (AFLT) of each mobile station from base stations having known positions. 
     
     
       10. The method as claimed in  claim 1 , wherein the mobile stations comprise hybrid telephone handsets including global satellite receivers, the positions of the mobile stations are determined from signals received by the mobile stations from global satellites, and the position of the base station is determined from the positions of the mobile stations using time difference of arrival. 
     
     
       11. The method as claimed in  claim 10  wherein said time difference of arrival is provided using Advanced Forward Link Trilateration (AFLT). 
     
     
       12. The method as claimed in  claim 1 , wherein the mobile stations comprise hybrid telephone handsets including global satellite receivers, the positions of the mobile stations are determined from signals received by the mobile stations from global satellites, said base stations comprise at least one Wireless LAN base station, and the position of said Wireless LAN base station is determined from the positions of the mobile stations in communication with said Wireless LAN base station, using Wireless LAN signals. 
     
     
       13. The method of  claim 12  wherein the Wireless LAN base station comprises a WiFi access point. 
     
     
       14. The method as claimed in  claim 1 , wherein the step of receiving a signal from said base station to said mobile station includes measuring signal path delays of the signals transmitted between the base station and the mobile stations to determine distances between the base station and the mobile stations. 
     
     
       15. The method of  claim 14  wherein said step of receiving a signal comprises measuring the time difference of arrival of said signal using TDOA system. 
     
     
       16. The method as claimed in  claim 15  wherein said step of measuring the time difference of arrival comprises measuring a phase shift using an AFLT system. 
     
     
       17. The method of  claim 14  wherein said step of receiving a signal comprises measuring the time of arrival of said signal using a TOA system. 
     
     
       18. The method of  claim 14  wherein said step of receiving a signal comprises measuring the round trip delay of said signal between said base station and said mobile station. 
     
     
       19. The method of  claim 1  wherein said step of comparing said calibration information comprises calculating a distance from said mobile station(s) to said base station. 
     
     
       20. The method of  claim 1  wherein said step of comparing said calibration information comprises determining an error in the distance from said mobile station(s) to said base station. 
     
     
       21. The method of  claim 1  wherein said step of calibrating the position of said base station comprises updating almanac information associated with said base station. 
     
     
       22. The method as claimed in  claim 1 , wherein the position of the base station antenna determined from the positions of the mobile stations is compared to a position for the base station contained in a base station almanac in order to verify the position for the base station contained in the base station almanac. 
     
     
       23. A wireless communication network comprising:
 a. a plurality of base stations, each having a unique location; 
 b. a BTS calibration server networked with said plurality of base stations; 
 c. a plurality of calibration-enabled mobile stations wirelessly communicating with at least one of said base stations, each of said calibration-enabled mobile stations having a BTS calibration program and a position location system for determining its position, and a means for receiving a signal from said base station to said mobile station; 
 d. means for requesting calibration information from at least one of said calibration-enabled mobile stations in communication with a base station; 
 e. means for determining if the mobile station is authorized to communicate calibration information, wherein said BTS calibration program provides privacy settings stored in said mobile station to indicate authorization to provide calibration information, and said means for determining if the mobile station is authorized to communicate calibration information farther comprises checking said privacy settings to verify that the mobile station is authorized to provide calibration information; 
 f. means for transmitting calibration information indicative of said position and said signal from said mobile station(s) to the BTS calibration server; 
 g. a base station almanac networked with said plurality of base stations and said BTS calibration server; and 
 h. means, in said BTS calibration server, for calculating a distance from said mobile station(s) to said base station, comparing it with base station almanac information associated with said base station, and calibrating the position of said base station responsive thereto. 
 
     
     
       24. The network as claimed in  claim 23 , wherein the position location system comprises a TDOA system for measuring distance. 
     
     
       25. The network as claimed in  claim 23 , wherein the position location system comprises a RTD system for measuring distance. 
     
     
       26. The network as claimed in  claim 23 , wherein the position location system comprises a TOA system for measuring distance. 
     
     
       27. The network as claimed in  claim 23 , wherein the position location system in said mobile stations include global satellite receivers, so that the positions of the mobile stations can be determined from signals received by the mobile stations from global satellites. 
     
     
       28. The network as claimed in  claim 23 , wherein the position location system in said mobile stations include an Advanced Forward Link Trilateration (AFLT) system that determines the positions of the mobile stations from base stations having known positions. 
     
     
       29. The network as claimed in  claim 23 , wherein the mobile stations comprise hybrid telephone handsets including global satellite receivers and AFLT systems. 
     
     
       30. The network of  claim 23 , wherein the means for calibrating the position of said base station comprises means for updating almanac information associated with said base station. 
     
     
       31. In a wireless communication network that includes a plurality of mobile stations in communication with one or more base stations, a method of determining a position of a base station, comprising:
 a. programming a group of mobile stations with a BTS calibration program, thereby providing a plurality of calibration-enabled mobile stations wherein each mobile station has a user, and wherein said users of said calibration-enabled mobile phones utilize the BTS calibration program to create privacy settings to indicate authorization to provide calibration information; 
 b. providing a BTS calibration server networked with said base station; 
 c. requesting calibration information from at least one of said calibration-enabled mobile stations in communication with a base station, and determining if the mobile station is authorized to communicate calibration information, including checking said privacy settings to verify that the mobile station is authorized to provide calibration information , and if there is no authorization then exiting operation before transmitting calibration information, otherwise completing operation; 
 d. determining a position of said calibration-enabled mobile station(s) in communication with said base station; 
 e. receiving a signal from said base station to said mobile station(s) in communication with said base station; 
 f. transmitting calibration information indicative of said position and said signal from said mobile station(s) to the BTS calibration server; and 
 g. in said BTS calibration server, comparing the calibration information with base station almanac information associated with said base station, and calibrating the position of said base station responsive thereto. 
 
     
     
       32. The method as claimed in  claim 31 , wherein the mobile stations have global satellite receivers, and the positions of the mobile stations are determined at least in part from signals received by the mobile stations from global satellites. 
     
     
       33. The method as claimed in  claim 31 , wherein the positions of the mobile stations are determined at least in part by Advanced Forward Link Trilateration (AFLT) of each mobile station from base stations having known positions. 
     
     
       34. The method of  claim 31  wherein the base station comprises a WiFi access point. 
     
     
       35. The method of  claim 31  wherein said step of comparing said calibration information comprises calculating a distance from said mobile station(s) to said base station, and determining an error in the distance from said mobile station(s) to said base station. 
     
     
       36. The method of  claim 31  wherein said step of calibrating the position of said base station comprises updating almanac information associated with said base station. 
     
     
       37. A method of maintaining accurate base station location information in a wireless communications system, comprising:
 receiving, at a mobile station, a request to report location calibration information related to at least one base station to a base station location calibration server, the requested location calibration information including at least a location estimate of the mobile station and information indicative of the mobile station's distance to the at least one base station;   determining position information sufficient to calculate the location estimate of the mobile station;   determining the information indicative of the mobile station's distance to the at least one base station; and   sending the requested location calibration information to the base station location calibration server.   
     
     
       38. The method of claim 37, further comprising:
 determining whether the mobile station is authorized to send the requested calibration information to the base station location calibration server,   wherein the sending step is performed if the mobile station is determined to be authorized.   
     
     
       39. The method of claim 37, wherein the receiving step receives the request from a calibration program that is being executed on the mobile station. 
     
     
       40. The method of claim 39, wherein the calibration program generates the request in response to a detected event. 
     
     
       41. The method of claim 40, wherein the detected event corresponds to the mobile station being in communication with the at least one base station. 
     
     
       42. The method of claim 37, wherein the receiving step receives the request from the base station location calibration server. 
     
     
       43. The method of claim 37, wherein the at least one base station includes a current serving base station of the mobile station. 
     
     
       44. The method of claim 37, wherein the at least one base station includes each base station detected at the mobile station. 
     
     
       45. The method of claim 37, wherein a position determination entity (PDE) assists the mobile station in determining the location estimate. 
     
     
       46. The method of claim 37, wherein the mobile station determines the location estimate without assistance from a position determination entity (PDE). 
     
     
       47. The method of claim 37, wherein the base station location calibration server is separate from a position determination entity (PDE) that is configured to assist mobile stations determine their location. 
     
     
       48. The method of claim 37, wherein the determining the location estimate of the mobile station is based on a wide area network (WAN) time difference of arrival (TDOA) protocol, a satellite position system (SPS) protocol or a hybrid system. 
     
     
       49. The method of claim 48, wherein the WAN TDOA protocol corresponds to an Advance Forward Link Trilateration (AFLT) protocol, the SPS protocol corresponds to a Global Positioning System (GPS) protocol and the hybrid system corresponds to a hybrid GPS/AFLT protocol. 
     
     
       50. The method as claimed in claim 37, wherein the mobile station comprises a hybrid telephone handset including a global satellite receiver, the position of the mobile station is determined from signals received by the mobile station from global satellites, said at least one base station comprises at least one Wireless LAN base station, and the position of said Wireless LAN base station is determined from the position of the mobile station in communication with said Wireless LAN base station, using Wireless LAN signals. 
     
     
       51. The method of claim 50, wherein the Wireless LAN base station comprises a WiFi access point. 
     
     
       52. The method of claim 37, wherein the information indicative of the mobile station's distance to the at least one base station corresponds is determined based on (i) measuring a phase shift in one or more downlink pilot signals from the at least one base station in accordance with an Advance Forward Link Trilateration (AFLT) protocol, (ii) measuring a time of arrival (TOA) of one or more downlink signals in accordance with a TOA protocol, and/or (iii) measuring a round-trip delay of one or more signals exchanged between the mobile station and the at least one base station. 
     
     
       53. The method of claim 37, wherein the sending step includes:
 establishing a dedicated base station calibration session with the base station location calibration server for the primary purpose of sending the requested calibration information.   
     
     
       54. A method of maintaining accurate base station location information in a wireless communications system, comprising:
 receiving, at a base station location calibration server, location calibration information related to at least one base station, the location calibration information including at least a location estimate of one or more mobile stations and information indicative of the one or more mobile stations' distance to at least one base station;   determining a location of the at least one base station based at least in part on the received location calibration information;   selectively updating a record of the at least one base station's location within a base station almanac based on the determined location of the at least one base station, the base station almanac configured to store locations of base stations of a wireless communication system.   
     
     
       55. The method of claim 54, wherein the location calibration information is sent from the one or more mobile stations responsive to a request initiated by a calibration program that is being executed on the one or more mobile stations. 
     
     
       56. The method of claim 54, further comprising:
 sending a request for the location calibration information to each of the one or more mobile stations,   wherein the receiving step receives the location calibration information from the one or more mobile stations in response to the request.   
     
     
       57. The method of claim 54, wherein the at least one base station includes a current serving base station of one or more mobile stations. 
     
     
       58. The method of claim 57, wherein the at least one base station includes each base station detected by the one or more mobile stations. 
     
     
       59. The method of claim 54, wherein the location estimate of the mobile station is based on a wide area network (WAN) time difference of arrival (TDOA) protocol, a satellite position system (SPS) protocol or a hybrid system. 
     
     
       60. The method of claim 59, wherein the WAN TDOA protocol corresponds to an Advance Forward Link Trilateration (AFLT) protocol, the SPS protocol corresponds to a Global Positioning System (GPS) protocol and the hybrid system corresponds to a hybrid GPS/AFLT protocol. 
     
     
       61. The method of claim 54, wherein the information indicative of the mobile station's distance to the at least one base station corresponds is based on (i) a phase shift in one or more downlink pilot signals from the at least one base station as measured at the one or more mobile stations in accordance with an Advance Forward Link Trilateration (AFLT) protocol, (ii) a time of arrival (TOA) of one or more downlink signals as measured at the one or more mobile stations in accordance with a TOA protocol, and/or (iii) a round-trip delay of one or more signals exchanged between the mobile station and the at least one base station. 
     
     
       62. The method of claim 54, wherein the sending step includes:
 establishing a dedicated base station calibration session with the one or more mobile stations for the primary purpose of receiving the requested calibration information.   
     
     
       63. The method of claim 54, wherein the determining step determines the location of the at least one base station based on multiple instances of the location calibration information, such that the location estimate of the at least one base station is triangulated from multiple indications of a given mobile station's distance to a given base station from a particular geographic location. 
     
     
       64. The method of claim 63, wherein the multiple instances of the location calibration information are either (i) received from the same mobile station at different locations, (ii) from different mobile stations at different locations, (iii) or a combination thereof. 
     
     
       65. The method of claim 54, wherein the selectively updating step includes:
 comparing the determined location of the at least one base station with a previously stored location of the at least one base station in the base station almanac; and   replacing the previously stored location of the record with the determined location based at least in part on the comparing step.   
     
     
       66. The method of claim 54, wherein the base station location calibration server is separate from a position determination entity (PDE) that is configured to assist mobile stations determine their location. 
     
     
       67. The method as claimed in claim 54, wherein the one or more mobile stations comprise a hybrid telephone handset including a global satellite receiver, the position of the one or more mobile stations are determined from signals received by the one or more mobile stations from global satellites, said at least one base station comprises at least one Wireless LAN base station, and the position of said Wireless LAN base station is determined from the position of the mobile station in communication with said Wireless LAN base station, using Wireless LAN signals. 
     
     
       68. The method of claim 67, wherein the Wireless LAN base station comprises a WiFi access point. 
     
     
       69. The method of claim 54, wherein the location of the at least one base station that is determined by the determining step corresponds to a geographical position of the at least one base station. 
     
     
       70. A mobile station in a wireless communications system, comprising:
 means for receiving a request to report location calibration information of at least one base station to a base station location calibration server, the requested location calibration information including at least a location estimate of the mobile station and information indicative of the mobile station's distance to the at least one base station;   means for determining position information sufficient to calculate the location estimate of the mobile station; and   means for determining the information indicative of the mobile station's distance to the at least one base station; and   means for sending the requested location calibration information to the base station location calibration server.   
     
     
       71. A base station location calibration server configured to maintain accurate base station location information in a wireless communications system, comprising:
 means for receiving location calibration information related to at least one base station, the location calibration information including at least a location estimate of one or more mobile stations and information indicative of the one or more mobile stations' distance to at least one base station;   means for determining a location of the at least one base station based at least in part on the received location calibration information;   means for selectively updating a record of the at least one base station's location within a base station almanac based on the determined location of the at least one base station, the base station almanac configured to store locations of base stations of a wireless communication system.   
     
     
       72. A mobile station in a wireless communications system, comprising:
 a receiver configured to receive a request to report location calibration information of at least one base station to a base station location calibration server, the requested location calibration information including at least a location estimate of the mobile station and information indicative of the mobile station's distance to the at least one base station;   a positioning location system configured to determine position information sufficient to calculate the location estimate of the mobile station and further configured to determine the information indicative of the mobile station's distance to the at least one base station; and   a transmitter configured to send the requested location calibration information to the base station location calibration server.   
     
     
       73. A base station location calibration server configured to maintain accurate base station location information in a wireless communications system, comprising:
 an interface configured to receive location calibration information related to at least one base station, the location calibration information including at least a location estimate of one or more mobile stations and information indicative of the one or more mobile stations' distance to at least one base station; and   a processor configured to determine a location of the at least one base station based at least in part on the received location calibration information and further configured to selectively update a record of the at least one base station's location within a base station almanac based on the determined location of the at least one base station, the base station almanac configured to store locations of base stations of a wireless communication system.   
     
     
       74. A non-transitory computer-readable storage medium comprising instructions, which, when executed by a mobile station in a wireless communications system, cause the mobile station to perform operations, the instructions comprising:
 program code to receive a request to report location calibration information of at least one base station to a base station location calibration server, the requested location calibration information including at least a location estimate of the mobile station and information indicative of the mobile station's distance to the at least one base station;   program code to determine position information sufficient to calculate the location estimate of the mobile station; and   program code to determine the information indicative of the mobile station's distance to the at least one base station; and   program code to send the requested location calibration information to the base station location calibration server.   
     
     
       75. A non-transitory computer-readable storage medium comprising instructions, which, when executed by a base station location calibration server configured to maintain accurate base station location information in a wireless communications system, cause the base station location calibration server to perform operations, the instructions comprising:
 program code to receive location calibration information related to at least one base station, the location calibration information including at least a location estimate of one or more mobile stations and information indicative of the one or more mobile stations' distance to at least one base station;   program code to determine a location of the at least one base station based at least in part on the received location calibration information;   program code to selectively update a record of the at least one base station's location within a base station almanac based on the determined location of the at least one base station, the base station almanac configured to store locations of base stations of a wireless communication system.