Telecommunications system

• US 20020002041A1
• Filed: 04/13/2001
• Published: 01/03/2002
• Est. Priority Date: 04/15/2000
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Lindgren, Hans Ake, Stille, Mats Ola
• Granted Patent: US 6,775,534 B2
• Time in Patent Office: Days
• US Class Current: 455/404.1
• CPC Class Codes: H04M 2242/04 for emergency applications
• CPC Class Codes: H04M 7/1205 where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks
• 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 76/50 for emergency connections

Abstract

There is described a system which, in a voice over IP radiotelecommunications system, allows a mobile station to make an emergency call, even though other calls would not be allowed at that time.

The mobile station includes an emergency call indication in the session activation request, and this is recognized by the network nodes, which then allow call set up.

Claims

1. A mobile communications device, capable of operating in a packet data communications network, the device comprising:

means for analysing a dialled number,

the device being adapted, in the event that a dialled number is indicative of an emergency call, to send a session activation request which includes an emergency call indication.

2. A mobile communications device as claimed in claim 1, the device being adapted to send the session activation request, in the event that a dialled number is indicative of an emergency call, even if the device has no SIM.

3. A method of handling an emergency call in a mobile device capable of operating in a packet data communication network, the method comprising:

analysing a dialled number; and

if the dialled number is indicative of an emergency call, sending a session activation request which includes an emergency call indication.

4. A method as claimed in claim 3, comprising sending the session activation request if the dialled number is indicative of an emergency call, even if the mobile device has no SIM.

5. A network node for use in a pocket data communications network, the node comprising means for detecting an emergency call indication in a received session activation request, and being adapted, in the event that an emergency call indication is detected, to set up a call even if normal call setup criteria are not met.

6. A node as claimed in claim 5, wherein the mode is a SGSN element.

7. A node as claimed in claim 6, wherein the node is adapted, in the event that an emergency call indication is detected, to set up a call even if the received session activation request includes no mobile station identifier.

8. A node as claimed in claim 6, adapted, in the event that an emergency call indication is detected, to create a packet session with a GGSN, including a further emergency call indication.

9. A node as claimed in claim 5, wherein the mode is a GGSN element.

10. A node as claimed in claim 7, adapted, in the event that an emergency call is detected, to return a message indicating a call server local to a calling device.

11. A method of operation of a node in a packet data communications network, the method comprising:

detecting an emergency call indication in a received session activation request, and

if an emergency call indication is detected, setting up a call even if normal call setup criteria are not met.

12. A method as claimed in claim 11, wherein the mode is a SGSN element, and the method further comprises:

if an emergency call indication is detected, creating a packet session with a GGSN, including a further emergency call indication.

13. A method as claimed in claim 11, wherein the mode is a SGSN element, and the method further comprises, in the event that an emergency call indication is detected, setting up a call even if the received session activation request includes no mobile station identifier.

14. A method as claimed in claim 11, wherein the mode is a GGSN element, and the method further comprises:

if an emergency call indication is detected, returning a message indicating a call server local to a calling device.