Observing a moving subscriber on the basis of handover commands

• US 20060009223A1
• Filed: 09/19/2005
• Published: 01/12/2006
• Est. Priority Date: 03/24/2003
• Status: Active Grant

• Current Assignee: Elisa Oyj
• Original Assignee: Elisa Matkapuhelinpalvelut Oy (Elisa Oyj)
• Inventors: Nykopp, Juha, Knuuttila, Olli, Kiviranta, Veli-Matti
• Granted Patent: US 7,826,857 B2
• Time in Patent Office: Days
• US Class Current: 455/436
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A location of a subscriber can be observed by means of a mobile network in a completely anonymous way, without a subscriber identifier or a temporary subscriber identifier. At first, a method extracts from a first time slot of a radio channel a message which includes information about a second time slot of a radio channel. The first time slot of a radio channel discloses the current cell of the subscriber and the second time slot of a radio channel discloses a new cell of the subscriber. A location of the subscriber is determined on the basis of the current and the new cell. This location is approximately situated in a geographical intersection area of the current and the new cell. Different kinds of statistics can be deduced from the observations concerning activities of subscribers.

Claims

1. A method for locating anonymously subscribers, said subscribers moving between cells of a mobile network, characterized by the steps of

extracting by extracting means from a first time slot of a radio channel a message which is sent from a base station and/or a base station controller of the mobile network, the message including a piece of information about a second time slot of a radio channel that is taken into use during a handover of a subscriber, the first time slot of a radio channel determining a current cell of the subscriber and the second time slot of a radio channel determining a new cell of the subscriber and

determining by a calculating server a location of the subscriber on the basis of the current cell and the new cell, said location being at least partly situated in the geographical intersection of the current and the new cell.

2. The method as in claim 1 characterized by the step of

attaching to information of said location a time stamp disclosing a point of time when the message was extracted and

storing the location information in a memory.

3. The method as in claim 2 characterized in that when the current cell of the subscriber is changed to a new cell and the subscriber is moving from the new cell to a subsequent cell, the method comprises the steps of

extracting from the second time slot of a radio channel a message transmitted in the mobile network, wherein the message includes a piece of information about a third time slot of a radio channel that is taken into use during a subsequent handover of the subscriber, the third time slot of a radio channel determining a current cell of the subscriber and the second time slot of a radio channel determining a subsequent cell of the subscriber and

determining another location of the subscriber on the basis of the new and the subsequent cell,

determining a distance travelled by the subscriber on the basis of said other location and the location information stored in the memory, and

determining a velocity of the subscriber on the basis of the distance travelled by the subscriber and the time stamp disclosing the point of time of the first extracted message, and on the basis of another time stamp disclosing a point of time of the second extracted message.

4. The method as in claim 1, characterized in that the extracting means comprises at least one signal analyzer which is adapted to send data the calculation server.

5. The method as in claim 1, characterized in that the message is extracted from signal traffic of at least one E1 connection.

6. The method as in claim 1 characterized in that the extracted message is a HandOver Command message.

7. A system for locating anonymously subscribers, said subscribers moving between cells of a mobile network, characterized in that the system is adapted to

extract by extracting means from a first time slot of a radio channel a message which is sent from a base station and/or a base station controller of the mobile network, the message including a piece of information about a second time slot of a radio channel that is taken into use during a handover of a subscriber, the first time slot of a radio channel determining a current cell of the subscriber and the second time slot of a radio channel determining a new cell of the subscriber, wherein said extracting means comprise at least one signal analyzer adapted to send data to a calculation server, and

determine by the calculation server a location of the subscriber on the basis of the current cell and the new cell, said location being at least partly situated in the geographical intersection of the current cell and the new cell.

8. The system as in claim 7, characterized in that the system is adapted to

attach to information of said location a time stamp disclosing a point of time when the message was extracted and

store the location information in a memory.

9. The system as in claim 8, characterized in that in order to be prepared for a situation in which the subscriber moves from the new cell to a subsequent cell the system is adapted to

extract from the second time slot of a radio channel a message transmitted in the mobile network, wherein the message includes a piece of information about a third time slot of a radio channel that is taken into use during a subsequent handover of the subscriber, the third time slot of a radio channel determining the current cell of the subscriber and the second time slot of a radio channel determining a subsequent cell of the subscriber and

determine another location of the subscriber on the basis of the new and the subsequent cell,

determine a distance travelled by the subscriber on the basis of said other location and the location information stored in the memory, and

determine a velocity of the subscriber on the basis of the distance travelled by the subscriber and the time stamp disclosing the point of time of the first extracted message, and on the basis of a time stamp disclosing a point of time of the second extracted message.

10. The system as in claim 7, characterized in that the message is extracted from signal traffic of at least one E1 connection.

11. The system as in claim 7, characterized in that the message is extracted through Abis interface.

12. The system as in claim 7, characterized in that the extracted message is a HandOver Command message.