Method of finding a physical location of a mobile telephone at a given time
A subscriber database, in at least one embodiment, stores RF level and timing advance information associated with all mobile telephones on a network. A location parameters database stores location data that associates different physical locations with RF levels/timing advance data that have been measured or inferred for those locations. The subscriber database is then interpreted for the purpose of establishing the location of a specific mobile telephone at a given time by matching the RF level/timing advance data for that specific mobile telephone against the location parameters database. This generates the location of the mobile telephone. The interpretation or querying of the subscriber database only occurs, however, when there is a request to establish the location of a specific mobile telephone, and not as an automated process applied to all mobile telephones on a network.
1. A method of finding a physical location of a mobile telephone at a given time, the method comprising:
storing, in a subscriber database, data that are derived from, or are values of, mobile telephone control parameters associated with multiple mobile telephones on a network;
storing, in a location parameters database, location data that associates different physical locations with data that are derived from, or are values of, mobile telephone control parameters, wherein at least some of the location data has been derived from a traffic monitoring system enabling points on a road network to be associated with values of some or all of the mobile telephone control parameters, and wherein at least some of the location data for an area extending beyond some or all roads in the road network has been derived through calculation or inference;
interpreting the data in the subscriber database for the purpose of establishing the location of a mobile telephone at the given time by:
using that data as a query that is run against the location parameters database in order to generate an answer that is the location of that mobile telephone, and
doing so only when there is an explicit request to establish the location of that one specific mobile telephone and not as part of a sequence of package of requests in relation to each of the multiple mobile telephones.
2. The method of claim 1 , wherein the data that are derived from, or are values of, mobile telephone control parameters, are obtained from a mobile telephone network.
3. The method of claim 1 , wherein the data that are derived from, or are values of, mobile telephone control parameters, includes the RF signal strength of neighboring base transceiver stations.
4. The method of claim 1 , wherein the data that are derived from, or are values of, mobile telephone control parameters includes RF levels from pairs of co-located base transceiver stations.
5. The method of claim 1 , wherein the data that are derived from, or are values of, mobile telephone control parameters includes timing advance information.
6. The method of claim 1 , wherein the data that are derived from, or are values of, mobile telephone control parameters includes transmission error rates.
7. The method of claim 1 , wherein the location parameters database is continuously or regularly updated as it receives reports from the traffic monitoring system.
8. The method of claim 1 , wherein the query triggers a match or search process to find the closest correlation between the mobile telephone control parameters specified in the search query and the mobile telephone control parameters in the location parameters database.
9. The method of claim 1 , wherein an answer to the query is the location of the mobile telephone, and that location is stored in the subscriber database.
10. The method of claim 1 , wherein the traffic monitoring system includes a GPS enabled navigation device that has an integrated mobile telephone.
11. The method of claim 1 , wherein the traffic monitoring system includes a GPS enabled navigation device that communicates with a mobile telephone over a short range wireless network.
12. The method of claim 1 , wherein at least some of the location data has been derived directly through measurement.