MOBILE STATION AND MOBILE COMMUNICATION METHOD

摘要

A mobile station and a mobile communication method are provided, which are, if being able to output a local ringing tone and a NW-provided ringing tone, capable of continuing a ringing tone outputted before a transition from LTE to 3G by aSRVCC even after the transition is made. A UE (100A) executes continuation processing (aSRVCC) of a 3G voice communication service if the mobile station makes a transition of the connection destination from LTE to 3G during an alert period when the other party in the voice communication service is being alerted. Further, the UE (100A) outputs a NW-provided ringing tone without outputting a local ringing tone based on data stored in the mobile station after making a transition to a second radio access system if aSRVCC is executed during a period when the NW-provided ringing tone is being outputted.

主权项

1. A mobile station capable of providing a voice communication service via an IP multimedia subsystem and configured to execute a transition from a first radio access system with no circuit-switched domain to a second radio access system with a circuit-switched domain, comprising:
a voice communication control unit configured to execute continuation processing of the voice communication service in the second radio access system if the mobile station makes a transition of a connection destination from the first radio access system to the second radio access system during an alert period when the other party in the voice communication service is being alerted; and a ringing tone control unit configured to output a NW-provided ringing tone or a local ringing tone during the alert period, the NW-provided ringing tone being transmitted from a network via the first radio access system or the second radio access system during the alert period, the local ringing tone being based on data stored in the mobile station, wherein the ringing tone control unit outputs the NW-provided ringing tone based on that the NW-provided ringing tone is being outputted before the continuation processing of the voice communication service, without outputting the local ringing tone, after a transition to the second radio access system if the voice communication control unit executes the continuation processing of the voice communication service during a period when the NW-provided ringing tone is being outputted.