SYSTEM AND METHOD FOR EXTRACTION OF LOCATION RELATED DATA IN A WIRELESS COMMUNICATION SYSTEM

• US 20090233625A1
• Filed: 03/11/2008
• Published: 09/17/2009
• Est. Priority Date: 03/11/2008
• Status: Active Grant

• Current Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Original Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Inventors: Ferguson, Jeffrey D.
• Granted Patent: US 8,781,503 B2
• Time in Patent Office: Days
• US Class Current: 455/456.500
• 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 92/12 between access points and access point controllers

Abstract

A system and method to collect data related to the geographical location of a mobile station communicating with a GSM network and to use the location related data to determine the geographical location of the mobile station. A tap is place in an Abis link between a base station and a base station controller, the tap providing a copy of a signal carried by the Abis link. The copy signal is routed to a protocol analyzer that extracts location related data from the copy signal. A location processor uses the location data to determine the geographical location of the mobile station. The geographical location data is used by a data analyzer to provide location based services, such as estimating traffic intensity and speed of mobile stations.

Claims

1. A system to provide location-based services for a mobile station in communication with a base station, the base station communicating with a base station controller via a communication link, comprising:

a tap on the communication link between the base station and the base station controller, the tap configured to provide a copy of a signal transmitted on the communication link;

a protocol analyzer configured to extract data from the signal copy, the extracted data related to a location of the mobile station; and

a location processor configured to receive the extracted data and derive location data therefrom, the location data being indicative of the location of the mobile station.

2. The system of claim 1 wherein the tap is a physical tap of the communication link configured to provide a copy of the signal by splitting the signal.

3. The system of claim 1 wherein the tap is a digital cross connect configured to receive the signal, regenerate the signal, and generate the copy of the signal.

4. The system of claim 1 wherein the communication link is constructed in conformance with an industry standard for an Abis interface.

5. The system of claim 1 wherein the communication link is an electrical link, the communication signal is an electrical signal and the tap is an electrical tap.

6. The system of claim 1 wherein the communication link is an optical link, the communication signal is an optical signal and the tap is an optical tap.

7. The system of claim 1 wherein the extracted data includes contents of one or more specific data fields in the copy of the signal;

and

wherein the protocol analyzer further comprises one or more probes, each probe configured to filter out the contents of a specific data field in the signal copy.

8. The system of claim 1 wherein the extracted data is Received Signal Strength Indication (RSSI) data related to the location of the mobile station associated with the base station.

9. The system of claim 1 wherein the extracted data is Global Positioning System (GPS) data related to the location of the mobile station associated with the base station.

10. The system of claim 1, further comprising a data analyzer configured to process the location data and provide location based services.

11. The system of claim 10 wherein the data analyzer is configured to perform statistical modeling of vehicular traffic through a geographical area covered by the base station, the modeling based on the derived mobile station location data.

20. The system of claim 1 wherein the extracted data is Global Positioning System (GPS) data related to the location of the mobile station associated with the base station.

12. A method to provide location-based services for a mobile station in communication with a base station, the base station communicating with a base station controller via a communication link, comprising:

tapping the communication link between the base station and the base station controller to provide a copy of a signal transmitted on the communication link;

extracting data from the copy of the signal, the data extracted related to a location of the mobile station associated with the base station; and

deriving location data from the extracted data, the location data being indicative of the location of the mobile station.

13. The method of claim 12 wherein tapping the communication link comprises physically splitting the signal into at least two portions including the copy of the signal and a continuing portion of the signal.

14. The method of claim 12 wherein tapping the communication link comprises:

receiving the signal;

regenerating the signal; and

generating the copy of the signal.

15. The method of claim 14 wherein generating the copy of the signal comprises:

analyzing the signal into component channels;

excluding channels from the copy of the signal, the excluded channels not containing information related to the location of the mobile station.

16. The method of claim 12 wherein extracting data from the copy of the signal comprises:

identifying one or more data fields in the copy of the signal, the data fields containing information related to the location of the mobile station; and

extracting the contents of the one or more identified data fields.

17. The method of claim 12 wherein the extracted data comprises received signal strength indication (RSSI) measurement sets, each set including the RSSIs measured by the mobile station of control signals from base stations near the mobile station.

18. The method of claim 17 wherein deriving location data from the extracted data comprises:

comparing one of the received RSSI measurement sets with a database of predetermined RSSI measurement sets associated with geographical location data; and

selecting as the derived location data the geographical location data associated with the predetermined RSSI measurement set that most closely matches the one received RSSI measurement set.

19. The method of claim 17 wherein deriving location data from the extracted data comprises:

determining the distances from the mobile station to the base stations near the mobile station using one of the RSSI measurement sets and an algorithm based on a Radio Frequency propagation model; and

determining the derived location data by triangulation using the determined distances and data relating to the geographical locations of the base stations.

21. The method of claim 12 further comprising providing location based services using the location data.