System and method relating to cellular communications

• US 5,956,652 A
• Filed: 01/21/1997
• Issued: 09/21/1999
• Est. Priority Date: 12/30/1994
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Eriksson, Dick
• Primary Examiner(s): Bost, Dwayne D.
• Assistant Examiner(s): MAUNG, NAY AUNG
• Application Number:
  US08/786,552
• Time in Patent Office: 973 Days
• Field of Search: 455/422, 455/426, 455/432, 455/433, 455/436, 455/446, 455/524, 455/554, 455/555, 455/560, 455/561, 370/522, 370/524
• US Class Current: 455/555
• CPC Class Codes: H04M 2203/1091 Fixed mobile conversion
• CPC Class Codes: H04M 3/42314 in private branch exchanges
• CPC Class Codes: H04W 8/10 between location register and external networks
• CPC Class Codes: H04W 84/16 WPBX [Wireless Private Branch Exchange]

Abstract

An arrangement providing access between a mobile communications network and a private network with at least one exchange or private branch exchange. Mobility serving devices are connected to the exchange or the private branch exchange over a first interface providing access to/from mobile cellular phones and over a second interface for calls to/from personal number users. A cellular telephone of the mobile cellular network connects to the exchange over an interface.

Claims

1. A telecommunications system comprising a cellular mobile communications network and a private network including at least one private branch exchange in which access is provided between the cellular communications network and the private network, and mobility serving means connected to the cellular mobile communications network over at least one interface providing access to/from mobile cellular telephones, wherein the mobility serving means is connected directly to a private branch exchange over a second interface for calls to/from personal numbers users and the second interface has the form of an extension access interface;

the private branch exchange being connected to the cellular mobile communications network on a dedicated trunk route supporting DTMF signalling.

2. The telecommunications system of claim 1, wherein the cellular network is connected indirectly to the mobility serving means;

and the at least one interface comprises a first interface interconnecting the private branch exchange with the mobility serving means, which first interface provides access to/from mobile cellular telephones, and a second interface connecting the cellular mobile communications network with the private branch exchange.

3. The telecommunications system of claim 2, wherein the private branch exchange is connected to a mobile switching center of the cellular mobile communications network.

4. The telecommunications system of claim 3, wherein the private branch exchange is connected to the mobile switching center over a dedicated trunk route supporting DTMF signalling.

5. The telecommunications system of claim 4, wherein the dedicated trunk route provides DTMF transmission of an A-party number.

6. The telecommunications system of claim 2, wherein the first interface is an ISDN Q-SIG interface.

7. The telecommunications system of claim 2, wherein the second interface is one of a PCM/CAS interface, an ISDN S₂ interface, and an analog extension line.

8. The telecommunications system of claim 2, wherein the mobility serving means is further connected to a number of radio exchanges via an ISDN S₂ -interface in order to also provide cordless mobility.

9. The telecommunications system of claim 1, wherein the cellular mobile communications network is connected directly to the mobility serving means via an interface supporting DTMF signalling with transmission of an A-number.

10. A mobile communication system comprising a mobile cellular communication network and a private network including a number of private branch exchanges and mobility serving means, each private branch exchange being directly connected via an interface to mobility serving means, wherein the cellular communication network directly interfaces the mobility serving means in order to provide cellular telephone access to the private network so that, when a call is made within a private numbering plan by a mobile cellular user, a connection is automatically established with the private branch exchange wherein the connection at least includes an extension access interface.

11. A method for providing a cellular telephone of a cellular mobile communications network with access to a private network having at least one private branch exchange when a call is made within a private numbering plan of the private network by automatically connecting the cellular telephone to the private branch exchange, comprising the steps of:

setting up a connection with the cellular mobile communications network to a trunk route to the private branch exchange;

transmitting an A-number;

making a transit call from the private branch exchange to mobility serving means connected to the private branch exchange over a first interface with the A-number;

analyzing a call number in the mobility server, examining if the call is to be routed to the private branch exchange, and then routing the call to the private branch exchange over a second interface that directly connects the mobility serving means to the private branch exchange the mobility serving means using the transmitted A-number when calling the private branch exchange; and

treating the call as a call from a personal number identical to the A-number.

12. The method of claim 11, wherein the mobility serving means uses the A-number when calling the private branch exchange.

13. The method of claim 11, wherein the A-number is converted in the mobility serving means before the mobility serving means calls the PBX.

14. A method for connecting a user of a private branch exchange to a mobile cellular telephone, wherein the mobile cellular telephone is associated with a personal number, comprising the steps of:

from the private branch exchange, calling a mobility serving means connected directly thereto over a second extension access interface assigned to the personal number in order to identify the call number;

in the mobility serving means, converting the personal number to a public cellular number;

routing the call to the private branch exchange over a first interface;

in the private branch exchange, handling the call as an ordinary transit call;

from the private branch exchange, calling a mobile switching center of a cellular network via an interface supporting DTMF signalling with transmission of an A-number, wherein the mobile switch center handles the call as an ordinary call to the mobile cellular telephone.

15. The method of claim 14, wherein a user of the private branch exchange is an internal party of the private branch exchange.

16. The method of claim 14, wherein a user of the private branch exchange is an external party calling through the private branch exchange.