When acquiring a PRL, a mobile phone judges whether the newly acquired PRL contains a base station satisfying a selection condition specifying (i) a communication mode, (ii) whether a base station available via a roaming service is selectable, and (iii) a data communication mode. On judging that such a base station is contained, the mobile phone retains the current selection condition. On judging, on the other hand, that such a base station is not contained, the mobile phone changes the selection conditions so that all the base stations contained in the PRL are made selectable for communication.
1. A mobile phone for selecting and communicating with a base station that satisfies a selection condition, the selecting being made based on roaming information indicating a plurality of base stations and a type of each base station, the mobile phone comprising:
a receiving unit operable to receive the selection condition indicating a type of base station specified by a user;
a storing unit operable to store the received selection condition;
an acquiring unit operable to acquire roaming information;
a roaming information storage unit operable to store the acquired roaming information;
a judging unit operable to judge, on acquisition of the roaming information by the acquiring unit, whether any base station indicated in the acquired roaming information satisfies the selection condition stored in the storage unit; and
a control unit operable, when the judging unit judges that none of the base stations indicated in the acquired roaming information satisfies the selection condition stored in the storage unit, to modify the selection condition so that at least one of the base stations indicated in the acquired roaming information satisfies a new selection condition, wherein
the type of base station relates to a communication mode,
the receiving unit is operable to receive the selection condition indicating one or more communication modes specified by the user,
the judging unit is operable to make the judgment depending on whether any base station indicated in the roaming information supports any of said one or more communication modes indicated in the selection condition, and
the control unit is operable, when the judging unit judges negatively, to modify the selection condition so that the new selection condition indicates no specification of any particular communication mode.
2. The mobile phone according to claim 1 , wherein
the type of base station relates to whether a respective base station is available via a roaming service,
the receiving unit is operable to receive the selection condition indicating whether a base station available via a roaming service is specified by the user to be selectable, and
the judging unit is operable to make the judgment depending on whether a base station indicated in the roaming information is available via a roaming service.
3. The mobile phone according to claim 2 , wherein
the control unit is operable, when the judging unit judges negatively, to modify the selection condition so that the new selection condition indicates no specification as to whether a base station available via a roaming service is selectable.
4. A mobile phone for selecting and communicating with a base station that satisfies a selection condition, the selecting being made based on roaming information indicating a plurality of base stations and a type of each base station, the mobile phone comprising:
a receiving unit operable to receive the selection condition indicating a type of base station specified by a user;
a storing unit operable to store the received selection condition;
an acquiring unit operable to acquire roaming information;
a roaming information storage unit operable to store the acquired roaming information;
a judging unit operable to judge, on acquisition of the roaming information by the acquiring unit, whether any base station indicated in the acquired roaming information satisfies the selection condition stored in the storage unit;
a control unit operable, when the judging unit judges that none of the base stations indicated in the acquired roaming information satisfies the selection condition stored in the storage unit, to modify the selection condition so that at least one of the base stations indicated in the acquired roaming information satisfies a new selection condition;
a holding unit operable to store, under control by the control unit, the selection condition initially specified by the user before the modification by the control unit; and
a user specification judgment unit operable, when the acquiring unit acquires the roaming information after the modification of the user-specified selection condition by the control unit, to judge whether any base station indicated in a newly acquired roaming information satisfies the user-specified selection condition stored in the holding unit, wherein
the control unit is operable, when the user specification judging unit judges positively, to modify the new selection condition to be identical to the user-specified selection condition stored in the holding unit, irrespective of the judgment by the judging unit.
5. The mobile phone according to claim 4 , wherein
the type of base station relates to a communication mode,
the receiving unit is operable to receive the selection condition indicating one or more communication modes specified by the user, and
the judging unit is operable to make the judgment depending on whether any base station indicated in the roaming information supports any of said one or more communication modes indicated in the selection condition.
6. The mobile phone according to claim 5 , wherein
the control unit is operable, when the judging unit judges negatively, to modify the selection condition so that the new selection condition indicates no specification of any particular communication mode.
7. The mobile phone according to claim 4 , wherein
the type of base station relates to whether a respective base station is available via a roaming service,
the receiving unit is operable to receive the selection condition indicating whether a base station available via a roaming service is specified by the user to be selectable, and
the judging unit is operable to make the judgment depending on whether a base station indicated in the roaming information is available via a roaming service.
8. The mobile phone according to claim 7 , wherein
the control unit is operable, when the judging unit judges negatively, to modify the selection condition so that the new selection condition indicates no specification as to whether a base station available via a roaming service is selectable.