Inter-System Hand-Over of a Mobile Terminal Operable with a First and a Second Radio Access Network

Abstract

A method and device for initiation a mobile originating service-based inter-system handover. At least two radio access networks (RANs) of different types, i.e. RAN of a first type and a RAN of a second type. A dual-mode mobile terminal communicates with the communication system via the RAN of the first type. The initiation of the inter-system handover is included in a transmission including a bearer capability (BC) field. The BC field indicates that a requested service is only operable with the RAN of the second type. In particular, at least one BC field is set to a parameter value, which serves as indication for the receiving network and its processing entities, respectively, which receiving network indicated to carry out the inter-system handover initiated by the mobile terminal.

1 . A mobile terminal for initiating an inter-system handover in a communication network, wherein the communication network comprises at least a radio access network of a first type and a radio access network of a second type, wherein the mobile terminal is capable of operating in at least the radio networks of the first type and the second type, in a case of a mobile terminating call, the mobile terminal configured to:
 encode a message with one or more information elements including at least one field indicating that a requested service is only operable with the radio access network of the second type, and   transmit the message to a network entity of the communication network using the radio access network of the first type to initiate the inter-system handover,   wherein the mobile terminal is accessing the communication network via the radio access network of the first type.   
     
     
         2 . The mobile terminal of  claim 1 , wherein the one or more information elements are one or more bearer capability information elements. 
     
     
         3 . The mobile terminal of  claim 2 , wherein the at least one field is at least one bearer capability field. 
     
     
         4 . The mobile terminal of  claim 3 , wherein the at least one bearer capability field has an inapplicable parameter value in view of the radio access network of the first type. 
     
     
         5 . The mobile terminal of  claim 3 , wherein the at least one bearer capability field selected from a plurality of bearer capability fields is distinguished in that at least one parameter value validity of the at least one bearer capability field differs in communications with the radio access networks of the first type and the second type. 
     
     
         6 . The mobile terminal of  claim 3 , wherein the message is a call confirmed message in accordance with a mobile terminating call establishment procedure. 
     
     
         7 . The mobile terminal of  claim 1 , wherein the message is a call confirmed message in accordance with a mobile terminating call establishment procedure. 
     
     
         8 . The mobile terminal of  claim 7 , wherein the call confirmed message is transmitted to a call control entity of a core network using the radio access network of the first type to initiate the inter-system handover. 
     
     
         9 . The mobile terminal of  claim 7  comprising a call control entity configured to perform the encoding. 
     
     
         10 . The mobile terminal of  claim 1  comprising a call control entity configured to perform the encoding. 
     
     
         11 . The mobile terminal of  claim 3 , wherein the at least one bearer capability information element includes all channel coding fields being set to “not acceptable”. 
     
     
         12 . The mobile terminal of  claim 3 , wherein the at least one bearer capability field includes a fixed network user rate field being set to a data rate value only applicable with the radio access network of the second type. 
     
     
         13 . The mobile terminal of  claim 1 , wherein the radio access network of the first type is a 2 nd  generation technology radio access network and the radio access network of the second type is a 3 rd  generation technology radio access network. 
     
     
         14 . The mobile terminal of  claim 3 , wherein the radio access network of the first type is a 2 nd  generation technology radio access network and the radio access network of the second type is a 3 rd  generation technology radio access network. 
     
     
         15 . The mobile terminal of  claim 14 , wherein the radio access network of the first type is a GSM/GPRS, global system for mobile communications/general packet radio system, radio access network and the radio access network of the second type is a WCDMA, wideband code division multiple access, radio access network. 
     
     
         16 . The mobile terminal of  claim 1 , wherein the one or more information elements are Bearer Capability Information Elements (BCIE). 
     
     
         17 . The mobile terminal of  claim 1 , wherein the message enables the network entity to determine whether to effectuate the inter-system handover. 
     
     
         18 . A mobile terminal for initiating an inter-system handover in a communication network, wherein the communication network comprises at least a radio access network of a first type and a radio access network of a second type, wherein the mobile terminal is capable of operating in at least the radio networks of the first type and the second type, the mobile terminal comprising:
 a call control entity, in a case of a mobile terminating call, configured to encode a message with one or more information elements including at least one field indicating that a requested service is only operable with the radio access network of the second type; and   a radio frequency interface configured to transmit the message to a network entity of the communication network using the radio access network of the first type in order to initiate the inter-system handover, wherein the mobile terminal is accessing the communication network via the radio access network of the first type.   
     
     
         19 . The mobile terminal of  claim 18 , wherein the one or more information elements are one or more bearer capability information elements. 
     
     
         20 . The mobile terminal of  claim 19 , wherein the at least one field is at least one bearer capability field. 
     
     
         21 . The mobile terminal of  claim 18 , wherein the message enables the network entity to determine whether to effectuate the inter-system handover. 
     
     
         22 . The mobile terminal of  claim 18 , wherein the one or more information elements are Bearer Capability Information Elements (BCIE). 
     
     
         23 . A mobile terminal for initiating an inter-system handover in a communication network, wherein the communication network comprises at least a radio access network of a first type and a radio access network of a second type, wherein the mobile terminal is capable of operating in at least the radio networks of the first type and the second type, the mobile terminal comprising:
 a call control entity, in a case of a mobile terminating call, configured to encode a message with information including at least one bearer capability field indicating that a requested service is only operable with the radio access network of the second type; and   a radio frequency interface configured to transmit the message to a network entity of the communication network using the radio access network of the first type in order to initiate the inter-system handover, wherein the mobile terminal is accessing the communication network via the radio access network of the first type.   
     
     
         24 . The mobile terminal of  claim 23 , wherein the information comprises one or more bearer capability information elements. 
     
     
         25 . The mobile terminal of  claim 23 , wherein the message enables the network entity to determine whether to effectuate the inter-system handover. 
     
     
         26 . The mobile terminal of  claim 23 , wherein the information comprises a Bearer Capability Information Element (BCIE).